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Postgres Plus xDB Replication Server User's Guide

1. See Section 5 1 2 2 Copyright 2012 EnterpriseDB Corporation All rights reserved 383 Postgres Plus xDB Replication Server with Multi Master User s Guide For a Postgres publication database in a single master replication system verify that the publication database user has the CREATE ON DATABASE privilege on the publication database the CREATE and USAGE privileges on the schema containing the publication tables and views and is the owner of the publication tables Alternatively use a superuser for a Postgres publication database user name See Section 5 1 2 3 For the master definition node in a multi master replication system verify that the publication database user is a superuser has the privilege to modify pg_catalog tables and is the owner of the publication tables See Section 6 1 1 For a master node other than the master definition node in a multi master replication system verify that the master node database user is a superuser and has the privilege to modify pg_catalog tables See Section 6 1 2 Step 6 Verify that the necessary privileges have been granted to the subscription database user For an Oracle subscription database verify that the subscription database user has CONNECT and RESOURCE privileges For a Postgres subscription database verify that the subscription database user is a superus
2. cce 372 8 3 44 Cleaning Up All Replication History cleanrephistory cessor 373 9 Appendix enn P SN RSE 374 9 1 Source and Target Database Server Configurations ssesseseserrereesrrereeereeee 374 9 1 1 Advanced Server Compatibility Configuration Modes eeeeeeeeeeees 374 9 1 2 Permitted Source and Target Configurations ccceeeeeeeseeeeeeeeeeeteeeees 374 9 2 solving Probl Bisa ow cccrsssesccssssscssssesssssscsssscesesssesenscesenaseesnacceenacees 375 OGPMETOT Messages AMUMIMEMID ssssccessscccsssrcesssssessscsssssnsessnccssssesencesenaceseaseeses 375 9 2 2 ite tPLook for Erros escccesccesseececeeseeceecceseeeceeeeseeeteccenseeseetees 380 9 2 3 COMME TO Dlg CHGMRMSE 559 0452 sacrnascss gashetitaa dtd aunee ends cease 382 9 2 4 Troubleshooting Aga ccscccsssscesssssessssesssssessaccsssancessasesenssesensceesnaseeens 384 9 3 Miscellaneous xDB Replication Server Processing TOpiIcs cesceeeeeeees 395 9 3 1 Publication and Subscription Server Configuration Options 0 395 9 3 2 Encrypting the Password in the xDB Replication Configuration File 403 O33 Wing a Cron EX Pressi ON ait gic tons n n e n ae 404 9 3 4 Disabling Foreign Key Constraints for Snapshot Replications 406 9 3 5 Quoted Identifiers and Default Case Translation 0 cceceesssseceeeeeees 407 9 3 6 Replicating the SQL Server SQL_VARIANT Data T
3. The query domain is changed again change from table dept to emp but this time the number of executions 4 for the same query domain updates 3 thru 6 exceeds bupBatchThresholdCount so the repeat counter is reset to 0 8 INSERT INTO emp 92 UPDATE REME The query domain is changed again INSERT statement to UPDATE statement and the number of executions 2 is less than bupBatchThresholdCount so the repeat counter is incremented to 1 Copyright 2012 EnterpriseDB Corporation All rights reserved 173 Postgres Plus xDB Replication Server with Multi Master User s Guide 10 UPDATE emp 11 INSERT INTO dept 12 DELETE FROM dept 13 INSERT INTO emp The query domain is changed between updates 10 and 11 between updates 11 and 12 and between updates 12 and 13 At this point the repeat counter has been incremented 3 more times to a value of 4 This now equals bupBatchThresholdRepeatLimit so processing is changed from BUP mode to BUS mode 5 8 2 2 Parallel Synchronization Parallel synchronization takes advantage of multi CPUs or cores in the system architecture by using multiple threads to apply transaction sets in parallel Parallel synchronization is applied in two ways e Multiple threads are used to load data for multiple tables in parallel from the source database Each thread opens a separate connection therefore you will observe multiple connections with the sourc
4. x08 ita Publication Subscription t DE Server Server Figure 22 Oracle database server on distributed host The same remote distribution can be used for the subscription database instead of or in addition to the publication database The advantages of a distributed host replication system are the following e The replication system and the database servers can each consume the resources of their own machines which can be individually selected and tuned e The publication and subscription databases can be in different geographic locations e You can enforce stronger database security if only the database server is allowed to run on a host The disadvantages of a distributed host replication system are the following e There may be a performance disadvantage since there is a network over which to push replication data especially if large snapshots are involved e Installation is more complex if the Postgres database must run on a different host than xDB Replication Server This involves installing Postgres on two separate hosts Copyright 2012 EnterpriseDB Corporation All rights reserved 61 Postgres Plus xDB Replication Server with Multi Master User s Guide e Configuration is more complex The network and firewalls must be properly configured to allow the distributed components to communicate When creating the replication system logical components the correct IP addresses of all component
5. Publication Server 192 168 10 102 9051 FA SMR Property Sa MMR Publication schema edb amp R Postgres Plus Advanced Server 1 Table count Wa ag edb dept rs edb emp Figure 118 Replication tree after adding a publication 6 3 Creating Additional Master Nodes Once you have created the master definition node you add additional databases to the multi master replication system by defining additional master nodes This is done by creating additional publication database definitions subordinate to the MMR type node under the Publication Server node that contains the master definition node After the publication database definition is created a Publication Database node representing the master node appears in the replication tree of the xDB Replication Console The publication that was defined under the master definition node appears under the Publication Database node You must enter database connection information such as the database server network address database identifier and database login user name and password when you create the publication database definition The connection information is used by the publication server to access the publication tables when it performs replication Step 1 Make sure the database server for the master definition node is running and accepting client connections Step 2 Select the MMR type node under the same Publication Server node that contains the master defini
6. Enterprise The Enterprise PostgreSQL Company Postgres Plus xDB Replication Server with Multi Master User s Guide Postgres Plus xDB Replication Server with Multi Master build 57 August 22 2012 Postgres Plus xDB Replication Server with Multi Master User s Guide Version 5 0 by EnterpriseDB Corporation Copyright 2012 EnterpriseDB Corporation All rights reserved EnterpriseDB Corporation 34 Crosby Drive Suite 100 Bedford MA 01730 USA T 1 781 357 3390 F 1 9785895701 E info enterprisedb com www enterprisedb com Copyright 2012 EnterpriseDB Corporation All rights reserved 2 Postgres Plus xDB Replication Server with Multi Master User s Guide Table of Contents li ALTO oreen n ve Posanalad ad sais eetiscns anon deh eat eauasen a house nS 9 1 1 Typographical Conventions Used in this Guide eee eeeeeseesneceseeeeeeeenees 10 1 2 Other Conventions Used in this Guide 0 eee eeeeeeseecsseceseeeeeeeeseessaeenseenees 11 1 3 How t Use Ths G de aac osessl ceectl taconite lea sisipe 11 Be AVNET VIC Wiis Giada E A Aa A lee la E an ea alas adie EOE ee ENS 13 21 Why Use Replication tiio aena E a EE REN 13 2 1 1 Offloading Reporting and Business Intelligence Queries 0 cesses 13 2 1 2 Using Warm Standby Servers ccccsscecesreefeecsse AMR crasescnsscesneeees 13 2 1 3 Testing Systems in Parallel ceecesssceeeseofMeceseecce files a D 13 2 1 4 Migrating Data Mer a esc A N
7. E roin Servers General Realtime Monitor Replication History Publication Server 192 168 2 7 9051 4 MMR 2 54 sur Ss SM 4 Oracle 192 168 2 6 1521 xe pubu amp Publication schema Table count Subscription count W E EDB DEPT EE EDB EMP E A Subscription Server 192 168 2 7 9052 Cleanup Replication History Replication history has been removed Figure 181 Successful cleanup of replication history After replication history cleanup if you click the Replication History tab no history records appear File Publication Subscription Help BBUF OGRA 5 ba Replication Servers a eS Publication Server 192 168 2 7 9051 oof MMR Start time Status Duration TX count Type B E SMR Ej a Oracle 192 168 2 6 1521 xe pubu ag E E EDB DEPT H E EDB EMP esi g Subscription Server 192 168 2 7 9052 K General Realtime Monitor Replication History Figure 182 Replication History tab after replication history cleanup Copyright 2012 EnterpriseDB Corporation All rights reserved 255 Postgres Plus xDB Replication Server with Multi Master User s Guide 7 5 Managing a Publication After a publication has been created certain aspects of the underlying replication system environment might be subsequently altered for any number of reasons Attributes that might change include the network location of the publication database server the netwo
8. For example you might initially load the tables by running the Migration Toolkit from the command line or by using a backup from an external data source When you load the target tables using an offline snapshot special preparations must be taken to account for the following deviations from the default target table creation and loading process e In the typical default scenario xDB Replication Server creates the target table definitions when you define the subscription in a single master replication system or add an additional master node in a multi master replication system When using an offline snapshot creation of the target table definitions is expected to be your responsibility You must therefore prevent xDB Replication Server from creating the target table definitions e In the typical default scenario xDB Replication Server performs synchronization replication using batches of SQL statements If any statement in a batch results in an error all statements in the batch are rolled back When using an offline snapshot if there is the possibility that the external data source used to load the target tables already has transactions applied to it that are also recorded in the shadow tables of the source tables then you must perform the first synchronization replication in non batch mode This is because the batch of synchronization transactions may include SQL statements that have already been applied to the target which may result in
9. The following query uses a function named SQL VARIANT PROPERTY to show the values stored in column f2 and their data types LS SIG 2 gt SQL VARIANT PROPERTY 2 BaseType AS basetype 35 SO WANRIUANHY IPIROIRISUEY ic2 V Biaereulsialomn INS joieseal Salona 4 gt SOV ARSLAN TBP ROPE RIVE ii aes Cculen mASmscarle 5 gt FROM variant_tbl 6 gt GO idl E2 basetype precision scale IRA T 23 numeric 6 2 2 COOL int 10 0 Sy SL char 0 0 3 rows affected In the Postgres subscription database create a domain named sql_ variant with an underlying data type that is compatible with the values that are stored in the SQL Server SQL VARIANT column CREATE DOMAIN sql variant AS NUMERIC 6 2 After replication occurs the subscription table is created using the sql variant domain in place of the SQL VARIANT data type of the publication table At the bottom of the following Object Browser window note the presence of the sql variant domain under the Domains node of the public schema Copyright 2012 EnterpriseDB Corporation All rights reserved 409 Postgres Plus xDB Replication Server with Multi Master User s Guide File Edit Plugins View Management Tools Help olk zker Be la006 Properties X Statistics Dependencies Dependents Collations 0 Property Value Domains 0 E Name variant_tbl FTS Configur
10. This means using the default settings of defaultBatchUpdateMode BUS and switchBatchUpdateMode true the publication server starts out by applying updates with individual SQL statements When it encounters a stream of consecutive changes that can all be processed in a single prepared statement it will switch to using prepared SQL statements Note If you want a certain batch update mode used throughout all synchronization replications applied by a given publication server without switching update modes set the defaultBatchUpdateMode option to the desired mode in combination with switchBatchUpdateMode false For example if you only want prepared statements used set the following options defaultBatchUpdateMode BUP switchBatchUpdateMode false Note When Oracle is the subscription database synchronization replication always occurs in BUP mode as if the preceding two options were always set The reason for this is so large columns of TEXT data type from Postgres publications can successfully replicate to Oracle CLOB columns In BUS mode an individual Oracle SQL statement has a string literal maximum length of 4000 characters This limitation does not occur for prepared SQL statements that are used in BUP mode busBatchThresholdCount The busBatchThresholdCount option sets the number of consecutive updates of the same type that must be encountered in the shadow tables before the publication server switches from B
11. BitRock Installer lt Back Next gt Cancel Figure 41 xDB Control database information Note The database specified as the xDB Control database cannot be used as a publication database or a master node in a replication system Therefore it is suggested to choose a database name other than the given default Note For purposes of this example xdb is chosen as the xDB Control database name Note The information that you enter on this screen is saved to the xDB Replication Configuration file named etc edb repl conf XDB_HOME etc edb repl conf Copyright 2012 EnterpriseDB Corporation All rights reserved 79 Postgres Plus xDB Replication Server with Multi Master User s Guide on Windows hosts Whenever a publication server or subscription server on this host is started it obtains the connection information to the xDB Control database from this file After you have completed the Postgres Installation Details screen click the Next button Step 16 Only if publication server is a selected component Enter an available port on which the publication server will run Default port number is 9051 Click the Next button Publication Server Details Please specify a port on which publication server will run Port 9051 BitRock Installer lt Back Next gt Cancel Figure 42 Publication server details Step 17 Only if subscription server is a selected component Enter an available port on whic
12. Copyright 20 12 EnterpriseDB Corporation All rights reserved 332 Postgres Plus xDB Replication Server with Multi Master User s Guide Filter clause null Publication created In the following example a publication named analysts managers is created that contains the edb dept table and employees from the edb emp table who are analysts or managers The tables are in an Advanced Server database The replication method is snapshot only java jar edb repcli jar createpub analysts managers gt repsvrfile pubsvrfile prop S pubdbid 2 gt reptype s gt tables edb dept edb emp tablesfilterclause 2 job IN ANALYST MANAGER Creating publication Tables edb dept TABLE edb emp TABLE Filter clause null job IN ANALYST MANAGER Publication created The following example creates a publication for a multi master replication system where table edb dept is assigned node priority conflict resolution and latest timestamp as the standby conflict resolution strategy Table edb emp is assigned earliest timestamp conflict resolution and manual resolution the default as its standby strategy java jar edb repcli jar createpub emp pub gt repsvrfile pubsvrfile prop gt pubdbid 6 gt reptype t gt gt gt tables edb dept edb emp Comirlieiniaesoullimeinionn isi Bein Standbycontlictresolution Ll 23M gt
13. Copyright 2012 EnterpriseDB Corporation All rights reserved 360 Postgres Plus xDB Replication Server with Multi Master User s Guide Examples In the following example synchronization replication is performed on subscription dept _emp_sub of a single master replication system java jar edb repcli jar dosynchronize dept emp sub N gt repsvrfile subsvrfile prop Performing synchronize Synchronize done successfully In the following example synchronization replication is performed on publication emp pub of a multi master replication system Note that the repgrouptype m parameter is required in this case java Jar edb repcli jar dosynchronize emp pub gt repsvrfile pubsvrfile prop repgrouptype m Performing synchronize Publication synchronized successfully 8 3 36 Configuring a Single Master Schedule confschedule For SMR only The confschedule command creates a schedule as to when recurring replications are to be initiated for a single master replication system Synopsis confschedule subname repsvrfile subsvrfile remove jobtype s t realtime no_of sec daily hour minute weekly day of week hour minute monthly month day of month hour minute cronexpr cron expression If the remove parameter is specified then the schedule is deleted from the subscription No other parameters other than subname and repsvrfile can be specified in this case If the remove parame
14. Subscription Server 192 168 2 7 9052 HR Postgres Plus Advanced Server 192 168 2 7 5444 su Figure 58 Create Subscription icon 4 1 5 Subscription Management The Remove Subscription icon Snapshot icon Synchronize icon Configure Schedule icon and Remove Schedule icon are activated when a Subscription node is highlighted in the replication tree TE x08 Replication Conse Fie Publication Subscription Help gt ay Gy a 2 bd Replication Servers tg Publication Server 192 168 2 7 9051 S E Subscription Server 192 168 2 7 9052 S Postgres Plus Advanced Server 192 168 2 7 5444 su E sales_dept_sub Figure 59 Remove Subscription Snapshot Synchronize Configure Schedule and Remove Schedule icons 4 2 Saving Server Login Information When you use the xDB Replication Console to create a replication system you will need to register a publication server and a subscription server During this process you are Copyright 2012 EnterpriseDB Corporation All rights reserved 95 Postgres Plus xDB Replication Server with Multi Master User s Guide given the option to save the server s login information This section describes what happens if you select this option The following discussion applies to both publication servers and subscription servers These are generically referred to as servers in this discussion 4 2 1 Server Login File If you choose to save the login information the server
15. The following is a list of other conventions used throughout this document This guide applies to both Linux and Windows systems Directory paths are presented in the Linux format with forward slashes When working on Windows systems start the directory path with the drive letter followed by a colon and substitute back slashes for forward slashes Much of the information in this document applies interchangeably to the PostgreSQL and Postgres Plus Advanced Server database systems The term Postgres is used to generically refer to both PostgreSQL and Postgres Plus Advanced Server When a distinction needs to be made between these two database systems the specific names PostgreSQL or Advanced Server are used The installation directory path of the PostgreSQL or Postgres Plus Advanced Server products is referred to as POSTGRES INSTALL HOME For PostgreSQL Linux installations this defaults to opt PostgreSQL version_no For PostgreSQL Windows installations this defaults to C Program Files PostgreSQL version_no For Advanced Server Linux installations this defaults to opt PostgresPlus version_no For Advanced Server Windows installations this defaults to C Program Files PostgresPlus version_no The product version number is represented by version_no 1 3 How to Use This Guide The following is a list of suggested sections to read based upon your purpose for using this guide If you are interested in a general overview of xDB Replicati
16. The most common types of Oracle table partitioning are the following e Range Partitioning Ranges of values defined on a column determine which tablespace a row is stored e List Partitioning A list of values defined on a column determines which tablespace a row is stored e Hash Partitioning An algorithm on a column generates a hash key which determines which tablespace a row is stored Postgres does not support table partitioning in the same manner as Oracle However Oracle table partitioning can be implemented in Postgres using the two Postgres features called table inheritance and rules Postgres table inheritance allows you to create a parent table from which you can create one or more child tables that inherit the columns of the parent Each child is an independent table in its own right except that it includes the column definitions of its parent Rules can be defined on the parent table to direct which child table an inserted row is to be stored Since each child table can be stored in a different physical location the behavior associated with range or list partitioning can be reproduced The import PartitionAsTable option controls what happens when an Oracle partitioned table is part of the publication importPartitionAsTable true false The default value is false Depending upon the Oracle partitioned table type and the setting of the import PartitionAsTable option one of the following may occur e A s
17. H Publication Server 192 168 2 7 9051 eo Subscription Server 192 168 2 7 9052 Property Service status Stopped Subscription database count Not Available Figure 94 Subscription Server node You can perform the following actions on the server login file e Change the subscription server s login information host IP address port number user name and password that you last saved in the server login file e Delete the subscription server s login information that is currently saved in the server login file This is the default action which will require you to register the subscription server again the next time you open the xDB Replication Console e Resave the subscription server s login information in the server login file Each time you open the Update Subscription Server dialog box you must choose to save the login information if you want it recorded in the server login file The following steps change only the content of the server login file residing on the host under the current xDB Replication Console user s home directory These changes do not alter any characteristic of the actual subscription server daemon on Linux or service on Windows These changes affect only how a subscription server is viewed through the xDB Replication Console on this host by this user Step 1 The subscription server whose login information you want to save change or delete in the server login file
18. Postgres Plus xDB Replication Server with Multi Master User s Guide Database Figure 1 Publications in one database replicating to subscriptions in another database Database Database Figure 2 Publications replicating to two subscription databases Copyright 2012 EnterpriseDB Corporation All rights reserved 17 Postgres Plus xDB Replication Server with Multi Master User s Guide Database Database Database Figure 3 Publications in two databases replicating to one subscription database Publication 1 to Publication 2 to Subscription Publication Database With Database With Subscription Database Respect to Respect to Database Subscription 1 Publication 2 Figure 4 Cascading Replication Tables used in both a subscription and a publication The preceding diagram illustrates that a table that has been created as a member of a subscription can be used in a publication replicating to another subscription This scenario is called cascading replication Copyright 2012 EnterpriseDB Corporation All rights reserved 18 Postgres Plus xDB Replication Server with Multi Master User s Guide The following diagram illustrates a multi master replication system with three master nodes Figure 5 Multi master replication system 2 2 3 Single Master Master to Slave Replication xDB Replication Server performs master to slave replication when a single master replication system is implemented The publication
19. Step 4 Verify that the pg_hba conf file of the Postgres database server running the xDB Control database has an entry that allows access to the xDB Control database from the loopback address 127 0 0 1 by the user name in the xDB Replication Configuration file 9 2 4 2 Deleting the xDB Replication Server Metadata The xDB Replication Server metadata completely describes the replication system This metadata must be complete and correct in order for replication to occur properly In addition the configuration and maintenance operations performed through the xDB Replication Console or the xDB Replication Server CLI cannot be accomplished properly unless the metadata is complete and correct There may be occasions where the metadata becomes corrupted Either one or more tables containing metadata are inadvertently deleted or the data within the metadata tables becomes corrupted Typically corruption occurs in the form of the first case one or more metadata tables were deleted or the entire schema and its contents were deleted manually using an SQL utility rather than through the operation of the xDB Replication Console or xDB Replication Server CLI In these situations there is usually no other choice than to remove all of the remaining metadata database objects using the database management system s deletion functions which effectively deletes all replication systems that use the publication server and subscription server that access
20. The following example shows how to delete the jobs in the msdb database 1 gt USE msdb 2 gt GO Changed database context to msdb IEE pide lete peoo bimnane i sare pele anu ijob redbu 2 gt GO l gt we so delete Jos Cielo meme wise treet Jos eclo 2 gt GO The next example shows the deletion of the triggers on the non snapshot only publication tables 1 gt USE edb 2 gt GO Changed database context to edb le 2 gt DROP TRIGGER edb rrpd edo depr SP DRO PM LRNG GE Rae clon tara psige dom Spier 4 gt DROP TRIGGER edb rrpu_edb dept 5 gt DROP TRIGGER edb rrpd_edb emp 6 gt DROP TRIGGER edb rrpi_edb emp 7 gt DROP TRIGGER edb rrpu_edb_ emp 8 gt GO The metadata database objects under the pubuser schema are dropped as shown by the following 1 gt USE edb 2 gt GO Changed database context to edb le 2 gt DROP PROCEDURE 3 gt DROP PROCEDURE 4 gt DROP PROCEDURE 5 gt DROP PROCEDURE pubuser CleanupShadowTables pubuser ConfigureCleanUpJob pubuser ConfigureCreateTxSetJob pubuser CreateMultiTxSet les Jes es ex Copyright 2012 EnterpriseDB Corporation All rights reserved 391 Postgres Plus xDB Replication Server with Multi Master User s Guide 6 gt DROP PROCEDURE pubuser CreateTableLogTrigge
21. The xDB Replication Server metadata database objects are created in a schema named _edb replicator pub In order to create this schema the publication database user must have the CREATE ON DATABASE privilege on the publication database GRANT CREATE ON DATABASE edb TO pubuser Step 3 Grant the privileges required to create triggers on the publication tables The publication database user must be the owner of the publication tables and must have the CREATE and USAGE privileges on the schema containing the publication tables GRANT CREATE USAGE ON SCHEMA edb TO pubuser ALTER TABLE edb dept OWNER TO pubuser ALTER TABLE edb emp OWNER TO pubuser ALTER TABLE edb jobhist OWNER TO pubuser Copyright 2012 EnterpriseDB Corporation All rights reserved 106 Postgres Plus xDB Replication Server with Multi Master User s Guide Step 4 The publication database user must be able to read the tables and views that are to be included in publications GRANT SELECT ON edb dept TO pubuser GRANT SELECT ON edb emp TO pubuser GRANT SELECT ON edb jobhist TO pubuser GRANT SELECT ON edb salesemp TO pubuser Step 5 The publication database user must have the USAGE privilege on the schemas in which the tables and views reside that are to be included in publications GRANT USAGE ON SCHEMA edb TO pubuser 5 1 3
22. removed tables from publication y T Copyright 2012 EnterpriseDB Corporation All rights reserved 279 Postgres Plus xDB Replication Server with Multi Master User s Guide i 3 xDB Replication tion Conso bs Replication Servers oe Publication Server 192 168 2 7 9051 amp Basmr Gl oracte 192 168 2 6 1521 xe pubus ag H E EDB DEPT EE EDB EMP oo MMR B A Subscription Server 192 168 2 7 9052 AR Postgres Plus Advanced Server 192 1 Subscription count Figure 206 Publication minus removed table 7 5 3 3 Viewing the Filter Clause For SMR only The filter clause on a publication table can be seen a couple of different ways Step 1 Make sure the publication server whose node is the parent of the publication you wish to view is running and has been registered in the xDB Replication Console you are using See Section 5 2 1 for directions on starting and registering a publication server Step 2 Select the table whose filter clause you want to view The filter clause appears in the General tab of the information window Copyright 2012 EnterpriseDB Corporation All rights reserved 280 Postgres Plus xDB Replication Server with Multi Master User s Guide g Replication Servers G amp Publication Server 192 168 2 7 9051 8 SMR amp q Oracle 192 168 2 6 1521 xe pubus DEPT 2 sales_dept Schema EDB E PK attributes DEPTNO es EDB EMP Attributes count 3 Fa MMR Filt
23. repoqroupt ype m Creating publication Tables edb dept TABLE edb emp TABLE Filter clause null null Conflict Resolution Option Node Priority Earliest Timestamp Standby Conflict Resolution Option Latest Timestamp Manual Publication created 8 3 12 Printing a Publication List printpublist The printpublist command prints a list of publication names Synopsis printpublist repsvrfile pubsvrfile pubdbid dbid Parameters pubsvrfile The file containing the publication server login information Copyright 2012 EnterpriseDB Corporation All rights reserved 333 Postgres Plus xDB Replication Server with Multi Master User s Guide dbid If the pubdbid parameter is specified only the publication names subordinate to the publication database definition specified by dbid are printed If the pubdbid parameter is omitted all publication names subordinate to the publication server are printed Examples S java jar edb repcli jar printpublist repsvrfile pubsvrfile prop Pisticci Ow lelCalted OMS nn analysts managers dept_emp emp _ pub salesemp 8 3 13 Printing a List of Tables in a Publication printpublishedtables The printpublishedtables command prints a list of tables and views that belong to the given publication Synopsis printpublishedtables pubname repsvrfile pubsvrfile Parameters pubname The name of the publication whose tables and views are to be printed
24. s network location IP address and port number user name and password are stored in a server login file in a hidden location under the home directory of the operating system account with which you have opened the xDB Replication Console See Section 3 2 for the location of this file The following shows the Register Publication Server dialog box where the option to save login information is presented as a check box In this example 192 168 2 7 entered in the Host field 9051 entered in the Port field enterprisedb entered in the User Name field and an encrypted form of the password entered in the Password field are saved in the server login file for this publication server if user name and password validation are successful The values for User Name and Password that you enter are validated against the user name and password in the xDB Replication Configuration file residing on host 192 168 2 7 in this case The user name and password must successfully authenticate before registration of the publication server and saving of the publication server s login information in the server login file occur See Section 2 3 1 4 for information on the xDB Replication Configuration file GB Register Publication Server Host 192 168 2 7 Port 9051 UserName enterprisedb Password 08000606 V Save login information Register Cancel Figure 60 Save login information option for a publication serve
25. user name and password that you last saved in the server login file e Delete the publication server s login information that is currently saved in the server login file This is the default action which will require you to register the publication server again the next time you open the xDB Replication Console e Resave the publication server s login information in the server login file Each time you open the Update Publication Server dialog box you must choose to save the login information if you want it recorded in the server login file The following steps change only the content of the server login file residing on the host under the current xDB Replication Console user s home directory These changes do not alter any characteristic of the actual publication server daemon on Linux or service on Windows These changes affect only how a publication server is viewed through the xDB Replication Console on this host by this user Step 1 The publication server whose login information you want to save change or delete in the server login file must be running before you can make any changes to the file See Step 1 of Section 5 2 1 for directions on starting the publication server Step 2 Click the secondary mouse button on the Publication Server node and choose Update The Update Publication Server dialog box appears Copyright 2012 EnterpriseDB Corporation All rights reserved 257 Postgres Plus xDB Replication Server wi
26. view_name The name of the view whose filter clause is to be printed This value is case sensitive Examples In the following example the filter clause on Advanced Server table edb emp in publication analysts managers is printed java jar edb repcli jar printfilterclause analysts managers gt repsvrfile pubsvrfile prop table edb emp Filter clause for table edb emp job IN ANALYST MANAGER 8 3 17 Updating a Filter Clause updatefilterclause For SMR only The updatefilterclause command changes the filter clause of the specified table or view Synopsis updatefilterclause pubname repsvrfile pubsvrfile table schema_t table_ name schema v view name filterclause filter clause See Section 7 5 3 4 for additional information on updating a filter clause Note The schema name and table or view name that you supply as values for the table parameter are case sensitive Unless quoted identifiers were used to build the database objects Oracle names must be entered using uppercase letters for example EDB DEPT and Advanced Server names must be entered in lowercase letters for example Copyright 2012 EnterpriseDB Corporation All rights reserved 339 Postgres Plus xDB Replication Server with Multi Master User s Guide edb dept See Section 9 3 5 for additional information on quoted identifiers and case translation Parameters pubname The name of the publicatio
27. 14 2 1 5 Write Availability 0 2 eee ME ooe aooo ee ee dM cee ce gece eecenseeceteees 14 2 1 6 Write Scalability 0 0 0 ee ccsecccee Arcee O T 14 2 1 7 Localized Data ACCEeSS ggg Rg oe ice eeecceseenceeeeseertercesnees 14 2 2 Replication Concepts and D mnmitionigy Sage ceeecceseccossersoneescensees 14 2 2 1 Comparison of Single Master and Multi Master Replication 15 2 2 2 Publications and Subscriptions ceeseeceescecescceceecceceeceecesececseeeeceteeeesaeees 15 2 2 3 Single Master Master to Slave Replication ec ceeeeeeeseesseceeeeeeeeeeaees 19 2 2 4 Multi Master Bigg pagmMin eee eecceeececceescersscceseeeseceesceesscceeeeecentencentencesnees 20 PPA NCHTON GIR MMMM ss esccccesscecsscesssrcessaressesseessacssssaceessacesenaseecsacesenasens 22 2 2 6 Snapshot and Synchronization cceeseeceesceceececeeececeeceeceeeeeceseeeceteeeeseees 22 2 2 7 Snapshot Only PublicQMPOns cesscccssscssssccessscsssssssessscssesssesesasescsssceencess 23 2 2 8 Filters N nnn inaani siea 23 2 3 XxDB Replication Server Components and Architecture seeeeeeeeeeereereeeeee 24 23L Physica COMPONENTS i a in e n aaa Ses ot A E AEEA 24 2 3 2 Logica Components a a a RE E SER SNS 33 2 3 3 xDB Replication System Examples ecccceeseecescecsecceceeececeeeeeeeseeeeeeees 37 2 4 Designing a Replication System ssssssssessessseesseeesssetssressresseessee
28. 315 8 2 4 Using Encrypted Passwords in Text Files ssssnseessenssessesesseessseessresseeesee 317 8 2 5 Running xDB Replication Server CLI Using a Parameter File 0 0 317 8 3 xDB Replication Server CLI Commands cee ceeeceeceeeeeeeececeeeeeeeneeeesaeees 319 Sl z Gettine Help belpis 319 8 3 2 Printing the Version Number version sseesssssesssessssseresseesssressresserssee 320 8 3 3 Printing the xDB Replication Server Version Number repversion 320 8 3 4 Encrypting Passwords encrypt ceesseceesecesceceecceeneneeceeceeceeeeecseeeeenseees 321 8 3 5 Adding a Publication Database addpubdb sisenssneesessseessesesssresseessesssee 321 8 3 6 Printing Publication Database IDs printpubdbids eee eee eeeeeeeeeeeee 325 8 3 7 Printing Publication Database Details printpubdbidsdetails 325 8 3 8 Updating a Publication Database updatepubdb eee ceeeeeeeeeeeeeteeee 326 8 3 9 Removing a Publication Database removepubdb ceeceeeeeeeeteeeeeteees 328 8 3 10 Get Tables for a New Publication gettablesfornewpub eeeeeeeee 329 8 3 11 Creating a Publication CrgAlepubQiy SQMMMEOM sccssssscesssscssnsscseneeees 329 8 3 12 Printing a Publication List printpublist sssessseesseessesssesssseesssressresseessee 333 8 3 13 Printing a List of Tables in a Publication printpublishedtables 334 8 3 14 Adding Tables t
29. Alternatively click the secondary mouse button on the Replication Servers node and choose Register Subscription Server The Register Subscription Server dialog box appears Enter the values you supplied during the installation of xDB Replication Server unless otherwise specified e Host Network IP address of the host running the subscription server This is the network IP address used for sub_ipaddr inthe pg_hba conf file in Section 5 1 4 3 Do not use localhost for this field e Port Port number the subscription server is using This is the port number you specified on the Subscription Server Details screen in Step 17 of Section 3 1 e User Name Database superuser name that the subscription server uses to connect to the xDB Control database This is the user name you specified on the Postgres Installation Details screen in Step 15 of Section 3 1 e Password Password of the database superuser given in the User Name field e Save login information Check this box if you do not want to re register the subscription server each time you open the xDB Replication Console See Section 4 2 for additional information on the advantages and disadvantages of saving server login information Note The user name and password combination you enter is authenticated against the user name and password in the xDB Replication Configuration file residing on the host with the IP address you enter in the Host field Copyright 2012 EnterpriseDB Corporat
30. Creating a publication requires the following steps e Registering the publication server e Adding the master definition node e Creating a publication by choosing the tables for the publication along with the conflict resolution options 6 2 1 Registering a Publication Server Registering a publication server is done in a manner identical to single master replication See Section 5 2 1 for directions on registering a publication server Copyright 2012 EnterpriseDB Corporation All rights reserved 182 Postgres Plus xDB Replication Server with Multi Master User s Guide EB x08 Replication Console Build 37e File Publication Subscription Help BBWY OG eis ta Replication Servers 3 General Publication Databases ae Publication Server 192 168 10 102 9051 S SMR Property T MMR Service status Running Authentication Passed Publication database count 0 Figure 111 Replication tree after registering a publication server After you have successfully registered a publication server the replication tree of the xDB Replication Console displays a Publication Server node under which are the SMR and MMR type nodes Continue to build the multi master replication system under the MMR type node 6 2 2 Adding the Master Definition Node The first database to be identified to xDB Replication Server is the master definition node This is done by creating a publication database definition subordinate to the
31. The subscription database definition to be removed is identified by the subdbid parameter See Section 5 5 5 for additional information on removing a subscription database Parameters subsvrfile The file containing the subscription server login information dbid Copyright 2012 EnterpriseDB Corporation All rights reserved 354 Postgres Plus xDB Replication Server with Multi Master User s Guide The subscription database ID of the subscription database definition to be removed Examples The subscription database definition identified by subscription database ID 2 is removed java jar edb repcli jar removesubdb repsvrfile subsvrfile prop gt subdbid 2 Removing Subscription Database Subscription Database removed 8 3 31 Creating a Subscription createsub For SMR only The createsub command creates a new subscription Synopsis createsub subname subsvrfile subsvrfile subdbid dbid pubsvrfile pubsvrfile pubname pubname The createsub command adds a new subscription subordinate to the subscription database definition with the subscription database ID given by parameter subdbid See Section 5 3 3 for additional information on creating a subscription Parameters subname The subscription name to be given to the new subscription subsvrfile The file containing the subscription server login information of the subscription server under which the new subscription is subordinate dbid The
32. When the subscription server is started it uses the information in the xDB Replication Configuration file found on its host to connect to the xDB Control database 2 3 1 3 xDB Control Database The xDB Control database is the main metadata repository of replication systems Almost all information needed to control all aspects of the replication process is stored in the xDB Control database The following points should be noted about the xDB Control database e Each publication server uses one xDB Control database determined by the connection information in the xDB Replication Configuration file found on the publication server s host e Fach subscription server uses one xDB Control database determined by the connection information in the xDB Replication Configuration file found on the subscription server s host Copyright 2012 EnterpriseDB Corporation All rights reserved 28 Postgres Plus xDB Replication Server with Multi Master User s Guide e Ifthe publication server and subscription server are running on the same host they share the same xDB Control database e Ifthe publication server and subscription server are running on different hosts they may use the same or they may use different xDB Control databases determined by connection information in the xDB Replication Configuration files found on their respective hosts The metadata and configuration information gathered by or related to a given publication server or subscr
33. address id 2 address Node B Changes ADDR A ADDR A ADDR C successfully applied Synchronization pushes INode A changes to Node C Current address on Node C lt gt old value on Node A ADDR C lt gt ADDR hence conflict id 2 address id 2 address id 2 address ADDR A ADDR A ADDR C detected Latest change on Node C accepted and Node A change discarded No changes on Node B Node C changes pushed to Node A that is successfully applied id 2 address j 2 address id 2 address Node A change already ADDR C ADDR A ADDR C marked as discarded and hence is id 2 address id 2 address id 2 address All nodes arein sync ADDR C ADDR C ADDR C and have consistent state 6 7 Viewing Conflict History Conflict history shows the following types of events that occurred during synchronization replication e Uniqueness conflicts where two or more master nodes attempted to insert a row with the same primary key value or unique column value e Update update conflicts where two or more master nodes attempted to update the same column of the same row e Update delete and delete update conflicts where one master node attempted to update a row that was deleted by another master node Copyright 2012 EnterpriseDB Corporation All rights reserved 209 Postgres Plus xDB Replication Server with Multi Master User s Guide See Section 6 6 for more information on conflict res
34. gt repsvrfile pubsvrfile prop gt SCarily amp OO Configuring scheduler Job is successfully scheduled In the following example the schedule is removed from publication emp pub java jar edb repcli jar confschedulemmr 6 pubname emp pub gt repsvrfile pubsvrfile prop gt remove Configuring scheduler Scheduled job is removed 8 3 38 Print Schedule printschedule The printschedule command prints a recurring replication schedule Synopsis printschedule subname pubname repsvrfile subsvrfile pubsvrfile repgrouptype s m Copyright 2012 EnterpriseDB Corporation All rights reserved 365 Postgres Plus xDB Replication Server with Multi Master User s Guide For a single master replication system use printschedule subname repsvrfile subsvrfile For a multi master replication system use printschedule pubname repsvrfile pubsvrfile repgrouptype m Parameters subname For SMR only The name of the subscription for which the schedule is to be printed pubname For MMR only The name of the publication for which the schedule is to be printed subsvrfile For SMR only The file containing the subscription server login information pubsvrfile For MMR only The file containing the publication server login information repgrouptype Specify s if this command applies to a single master replication system Specify m if this command applies to a multi master replica
35. Copyright 2012 EnterpriseDB Corporation All rights reserved 194 Postgres Plus xDB Replication Server with Multi Master User s Guide Publication Service Add Database lem Database Type Postgres Plus Advanced Server Database Information 2 Please specify Postgres Plus Advanced Server database information Host 192 168 10 103 Port 5444 User mmruser Password Database mmrnode Node Priority Level 2 x V Replicate Publication Schema v Perform Initial Snapshot Snapshot Log Figure 122 Adding a master node with an initial snapshot If the snapshot is successful the replicated tables in the master node are loaded with the rows from the publication tables of the master definition node 6 4 Metadata Created in Master Nodes Creation of master nodes results in the creation of xDB Replication Server metadata database objects in each master node database Figure 74 of Section 5 2 4 shows the metadata database objects created in each master node You will also notice schema edb replicator pub in the xDB Control database Schema edb replicator pub and its database objects were created when the master definition node was added Copyright 2012 EnterpriseDB Corporation All rights reserved 195 Postgres Plus xDB Replication Server with Multi Master User s Guide Do not delete any of these database objects as the replication system metadata will become corrupted When you rem
36. Corporation All rights reserved 231 Postgres Plus xDB Replication Server with Multi Master User s Guide Publication Server 192 168 2 7 9051 S Subscription Server 192 168 2 7 9052 postgres Plus Advanced Server 192 tg H E sales_dept Figure 156 Selecting a subscription for removal of a schedule Step 2 For MMR only Select the Publication Database node representing the master definition node for which you wish to remove the schedule tq Replication Servers eae k 8 Publication Server 192 168 10 102 9051 B sur Postgres Plus Advanced Server 1 Bf emp_pub cP Postgres Plus Advanced Server Figure 157 Selecting a master definition node for removal of a schedule Copyright 2012 EnterpriseDB Corporation All rights reserved 232 Postgres Plus xDB Replication Server with Multi Master User s Guide Step 3 For SMR only Remove the schedule in any of the following ways e From the Subscription menu choose Schedule then Remove Schedule e Click the secondary mouse button on the Subscription node and choose Remove Schedule e Click the primary mouse button on the Remove Schedule icon Step 3 For MMR only Remove the schedule in any of the following ways e Click the secondary mouse button on the Publication Database node and choose Remove Schedule e Click the primary mouse button on the Remove Schedule icon ta Replication Servers E Publication Se
37. Figure 135 Selecting a publication in which to update conflict resolution options Step 3 Open the Conflict Resolution Options dialog box in any of the following ways e From the Publication menu choose Update Publication then Conflict Resolution Options e Click the secondary mouse button on the Publication node choose Update Publication and then choose Conflict Resolution Options Copyright 2012 EnterpriseDB Corporation All rights reserved 213 Postgres Plus xDB Replication Server with Multi Master User s Guide Replication Servers GE Publication Server 192 168 10 102 9051 Bf sur Ga MMR Conflict Resolution Options Figure 136 Opening the Conflict Resolution Options dialog box Step 4 For each table you can select the primary conflict resolution strategy and a standby strategy by clicking the primary mouse button over the appropriate box to expose a drop down list of choices Copyright 2012 EnterpriseDB Corporation All rights reserved 214 Postgres Plus xDB Replication Server with Multi Master User s Guide Figure 137 Updating conflict resolution strategies Step 5 Click the odai Bon and then n click OK in response to Conflict Resolution Options Ugfited Success g S Copyright 2012 EnterpriseDB Corporation All rights reserved 215 Postgres Plus xDB Replication Server with Multi Master User s Guide Conflict Resolution Options Published Table s Conflict Resolution Strat
38. General Replication Status In the xDB Replication Console view the replication history See Section 7 3 Copyright 2012 EnterpriseDB Corporation All rights reserved 380 Postgres Plus xDB Replication Server with Multi Master User s Guide 9 2 2 2 Snapshot Replication Failures View the log file found in the following path For Linux var log xdb rep buildnn mtk_ yyyymmddhhmiss log For Windows POSTGRES HOME enterprisedb edb replicator buildnna mtk yyyymm ddhhmiss log POSTGRES HOME is the home directory of the Windows postgres account enterprisedb account for Advanced Server installed in Oracle compatible configuration mode In the buildnn subdirectory nn is the xDB Replication Server build number The specific location of POSTGRES_HOME is dependent upon your version of Windows 9 2 2 3 Synchronization Replication Failures Check the database server log file The typical default location of these files is POSTGRES INSTALL HOME data pg_log 9 2 2 4 Publication and Subscription Server Startup Failures View the log files pubserver log and subserver 1log in the following directory For Linux var log xdb rep buildnn For Windows POSTGRES HOME enterprisedb edb replicator buildnn POSTGRES_ HOME is the home directory of the Windows postgres account enterprisedb account for Advanced Server installed in Oracle compatible configuration mode In the buildnn subdirectory nn is the xDB Replication Server b
39. Guide successful replication are applied whenever the next scheduled replication occurs Thus accumulated changes are never lost due to a missed replication For snapshot replications skipped scheduled replications present no problem since a snapshot replication replaces all of the data in the target tables with the current source data Step 1 For SMR only Select the Subscription node of the subscription for which you wish to create a schedule ta Replication Servers H e Publication Server 192 168 2 7 9051 tg Subscription Server 192 168 2 7 9052 E Postgres Plus Advanced Server 192 ag Sy sales_dept EDB DEPT H E EDB EMP Publication server Publication server port Scheduled job status Figure 143 Selecting a subscription on which to set a schedule Step 1 For MMR only Select the Publication Database node representing the master definition node The MDN field in the Property window is set to Yes for the master definition node Copyright 2012 EnterpriseDB Corporation All rights reserved 222 Postgres Plus xDB Replication Server with Multi Master User s Guide J xDB Replication Console tg Replication Servers oS Publication Server 192 168 10 102 9051 SMR Sa MMR 192 168 10 102 Postgres Plus Advanced Server 1 5444 y emp_pub Database edb H E edb dept User pubuser H E edb emp MDN Yes Publication count 1 Scheduled job status Not available
40. L for latest timestamp conflict resolution N for node priority conflict resolution or M for manual conflict resolution The specified conflict resolution applies to the table in the position given by ordinal tn counting from left to right in the tables parameter list If omitted the default is M repgrouptype Specify s if this command applies to a single master replication system Specify m if thi s command applies to a multi master replication system If omitted the default is s Examples In the following example a publication named dept emp is created that contains the EDB DEPT and EDB EMP tables of an Oracle database The replication method is synchronization java j ar edb repcli jar createpub dept _emp pubdbid 1 reptype t tables EDB DEPT EDB EMP repsvrfile pubsvrfile prop gt gt Creating Tables p blireationk n EDB DEPT TABLE EDB EMP TABLE Filter clause null null Publication created In the following example a publication named salesemp is created that contains the EDB SALESEMP view of an Oracle database The replication method is snapshot only java jar edb repcli jar createpub salesemp gt repsvrfile pubsvrfile prop gt pubdbid 1 gt reptype s views EDB SALESEMP Creating publication Tables EDB SALESEMP VIEW
41. Level 1 Figure 113 Successful master definition node test If an error message appears investigate the cause of the error correct the problem and repeat steps 1 through 4 When the publication database definition is successfully saved a Publication Database node is added to the replication tree under the MMR type node of the Publication Server node Copyright 2012 EnterpriseDB Corporation All rights reserved 185 Postgres Plus xDB Replication Server with Multi Master User s Guide File Publication Subscription Help Guy CUshis g Replication Servers B S Publication Server 192 168 10 102 9051 General ra SMR Property SEA MMR Host 192 168 10 102 i Postgres Plus Advanced Server 192 168 10 102 5444 edb pubuser MDN Port 5444 Database edb User pubuser MDN Yes Publication count 0 Figure 114 Replication tree after adding the master definition node The label MDN appears at the end of the node in the replication tree and in addition the MDN field is set to Yes in the Property window to indicate this is the master definition node 6 2 3 Adding a Publication Subordinate to the master definition node you create a publication that contains tables of the database Step 1 Select the Publication Database node From the Publication menu choose Create Publication Alternatively click the secondary mouse button on the Publication Database node and choose Crea
42. Multi Master User s Guide racle to Postgres replication system g xDB Replication Console or xDB Replication Server CLI Figure 11 Oracle to PostgreSQL or Advanced Server replication The following describes the logical components in the preceding diagram e The publication server to be used is identified by registering its network location user name and password e A publication database definition is created subordinate to the SMR type node under the publication server The Oracle database user name pubuser is specified in the definition along with the database network location and database identifier When you create a user named pubuser in Oracle a schema named pubuser is automatically created by Oracle at the same time The publication server creates database objects in the pubuser schema for the replication system s metadata when you create the publication database definition Copyright 2012 EnterpriseDB Corporation All rights reserved 38 Postgres Plus xDB Replication Server with Multi Master User s Guide e A publication named pub is created subordinate to the publication database definition The publication consists of table A in schema S1 and tables B and C in schema S2 e The subscription server to be used is identified by registering its network location user name and password e A subscription database definition is created subordinate to the subscription server The Postgres database user name subuser is
43. Next button Setup xDB Replication Server Welcome to the Postgres Plus xDB Replication Server Setup Wizard PostgreSQL Packaged by Enterprise The Enterprise Postgr SOL Company Figure 35 Setup xDB Replication Server Copyright 2012 EnterpriseDB Corporation All rights reserved 73 Postgres Plus xDB Replication Server with Multi Master User s Guide Step 11 Read the license agreement If you accept the agreement select the accept radio button and click the Next button License Agreement Please read the following License Agreement You must accept the terms of this agreement before continuing with the installation Limited Use Software License Agreement IMPORTANT READ CAREFULLY This Limited Use Software License Agreement Agreement is a legal document between you Customer and EnterpriseDB Corporation EnterpriseDB It is important that you read this document before using the EnterpriseDB provided software Software By clicking the I ACCEPT button or by installing or otherwise using the Software Customer agrees to be bound by the terms of this Agreement including without limitation the warrantiu disclaimers initations af liabiliti and accept the agreement Do you accept this license I do not accept the agreement Figure 36 License agreement BitRock Installer Step 12 Browse to a directory where you want the xDB Replication Server components installed or allow it to in
44. Plus xDB Replication Server with Multi Master User s Guide For Postgres only The schema edb replicator pub and all of its database objects are deleted from the publication database The following are the steps to remove the Publication Database node and equivalently the publication database definition Step 1 Make sure the publication server whose node is the parent of the publication database definition you wish to remove is running and has been registered in the xDB Replication Console you are using See Section 5 2 1 for directions on starting and registering a publication server Step 2 Select the Publication Database node that you wish to remove ta Replication Servers a e Publication Server 192 168 2 7 9051 B j SMR lM Oracle 192 168 2 6 1521 xe pubus of MMR A Subscription Server 192 168 2 7 9052 Figure 224 Selecting a publication database definition for removal Step 3 From the Publication menu choose Publication Database then Remove Database Alternatively click the secondary mouse button on the Publication Database node and choose Remove Database The Remove Publication Database confirmation box appears Step 4 In the Remove Publication Database confirmation box click the Yes button Copyright 2012 EnterpriseDB Corporation All rights reserved 300 Postgres Plus xDB Replication Server with Multi Master User s Guide Publication Server 192 168 2 7 9051 GBS sur mt lM
45. Postgres Plus xDB Replication Server Downloaded 6312 of 17585 KB 2104 KB Sec Elapsed time 0 00 32 Figure 32 Downloading progress Copyright 2012 EnterpriseDB Corporation All rights reserved 71 Postgres Plus xDB Replication Server with Multi Master User s Guide Step 8 When downloading of the xDB Replication Server package completes the following screen appears that starts the installation of xDB Replication Server Click the Next button Note You can check the Skip Installation box if you wish to install xDB Replication Server some other time StackBuilder Plus 2 0 4 All the installation files have now been successfully downloaded Please click the Next button to start the installations Note You must allow all installations to run to completion If you are prompted to restart the computer click No or Restart Later and manually restart your computer when all the installations have finished c Skip installation Enterprise The Enterprise PostgreSQL Company see ae Figure 33 Start installation Step 9 Select the installation language and click the OK button Copyright 2012 EnterpriseDB Corporation All rights reserved 72 Postgres Plus xDB Replication Server with Multi Master User s Guide Language Selection Please select the installation language English English a Figure 34 Installation language Step 10 In the Setup xDB Replication Server screen click the
46. Postgres Plus xDB Replication Server with Multi Master User s Guide port QOS Updating subscription dept _emp sub Subscription is updated successfully 8 3 40 Removing a Subscription removesub For SMR only The removesub command removes a subscription Synopsis removesub subname repsvrfile subsvrfile See Section 5 5 4 for additional information on removing a subscription Parameters subname The name of the subscription to be removed subsvrfile The file containing the subscription server login information Examples A subscription named dept _emp sub is removed S java jar edb repcli jar removesub dept_emp sub gt repsvrfile subsvrfile prop Removing subscription Subscription removed successfully 8 3 41 Scheduling Shadow Table History Cleanup confcleanupjob The confcleanupjob command creates a schedule as to when shadow table history is to be deleted Synopsis confcleanupjob pubdbid repsvrfile pubsvrfile disable enable hourly no_of hours daily hour weekly day of week hour Copyright 2012 EnterpriseDB Corporation All rights reserved 369 Postgres Plus xDB Replication Server with Multi Master User s Guide If the disable parameter is specified then the schedule is deleted No other parameters other than pubdbid and pubsvrfile can be specified in this case If the disable parameter is omitted then the enable parameter and one of parameters hourly daily or weekly
47. Postgres Plus xDB Replication Server with Multi Master User s Guide Changes on node A are applied to node B Changes on node A are applied to node C Changes on node B are applied to node A Changes on node B are applied to node C Changes on node C are applied to node A Changes on node C are applied to node B There may be circumstances where changes made on different nodes result in conflicts Section 6 6 discusses the types of conflicts that may occur and how they can be resolved The following steps describe how to initiate on demand synchronization replication Step 1 Select the Publication node under any master node Regardless of the master node chosen synchronization is applied to every master node pair in the replication system File Publication Subscription Help Re Replication Servers gt General Realtime Monitor Replication H Publication Server 192 168 10 102 9051 gt SMR Property Sa MMR Publication schema amp Postgres Plus Advanced Server 1 Table count oy emp_pub H E edb dept E edb emp i Postgres Plus Advanced Server 1 ag H E edb dept edb emp Figure 127 Selecting a master node publication for an on demand synchronization Step 2 Open the Synchronize dialog box in any of the following ways e Click the secondary mouse button on the Publication node and choose Synchronize e Click the primary mouse button on the Synchronize icon Copyright 2012 Enterpris
48. Preparing the Subscription Database This section discusses the preparation of a database that will be used as a subscription database The tables and views in a given publication must all be replicated to the same database This database is called the subscription database A subscription database user name must be created with the following characteristics e The subscription database user can connect to the subscription database e The subscription database user has the privileges to create database objects for the replicated tables and views from publications e The subscription database user has the privileges necessary to execute the TRUNCATE command on the replicated tables See Section 5 1 3 1 for preparation of a Postgres subscription database See Section 5 1 3 2 for preparation of an Oracle subscription database See Section 5 1 3 3 for preparation of a SQL Server subscription database 5 1 3 1 Postgres Subscription Database A database user name must be chosen or created to serve as the subscription database user The user name must have a password The subscription database user becomes the owner of the replicated database objects When creating the subscription database definition the subscription database user name is entered in the Subscription Service Add Database dialog box see Section 5 3 2 The subscription database user must also have the ability to run the TRUNCATE command on the subscription tables Thi
49. Registering Your xDB Replication Server Product Certain features of xDB Replication Server require you to register your xDB Replication Server product Currently full usage of the multi master replication feature following a trial period requires product registration Note Following expiration of the trial period xDB Replication Server operates in restricted mode which limits certain operations See Section 9 3 7 for details on restricted mode operation The current status of your trial period can be seen in the bottom right hand corner of the xDB Replication Console by selecting a publication server running under the instance of the xDB Replication Server product for which you want to see the status Copyright 2012 EnterpriseDB Corporation All rights reserved 87 Postgres Plus xDB Replication Server with Multi Master User s Guide File Publication Subscription Help USWY OBA ie g Replication Servers General Publication Databases i Publication Server 192 168 2 5 9051 a SMR Property EA MMR Service status Running Authentication Passed Publication database count 0 Trial License 45 days remaining gt m Figure 49 Product registration status Register your xDB Replication Server product by entering your Enterprise DB product license key at any time before or after the trial period ends Enter the license key by using the xDB Replication Console After you enter yo
50. Server Multiple Postgres or SQL Server databases can be added as publication databases by completing the Add Database dialog box for each database However unlike Oracle a given Postgres or SQL Server database can only be added once as a publication database definition 5 2 3 Adding a Publication Subordinate to a publication database definition you create publications that contain tables and views of the database identified in the publication database definition Step 1 Select the Publication Database node From the Publication menu choose Create Publication Alternatively click the secondary mouse button on the Publication Database node and choose Create Publication The Create Publication dialog box appears Step 2 Fill in the following fields under the Create Publication tab e Publication Name Enter a name that is unique amongst all publications Copyright 2012 EnterpriseDB Corporation All rights reserved 123 Postgres Plus xDB Replication Server with Multi Master User s Guide e Snapshot only replication Check the box if replication is to be done by snapshot only Tables included in a snapshot only publication do not require a primary key Tables included in publications on which synchronization replication is to be used must have primary keys e Publish Check the boxes next to the tables that are to be included in the publication If the Snapshot Only Replication box is checked then views appear in the Publish list
51. Server to SQL Server Replication The following is an illustration of a basic PostgreSQL or Advanced Server to SQL Server single master replication system A single publication in a PostgreSQL or Advanced Server database contains tables from two schemas that are replicated to a SQL Server database ostgres to SQL Server replication system xDB Replication Console or Schema do _edb_replicator_pub Objects Figure 17 PostgreSQL or Advanced Server to SQL Server replication The following describes the logical components in the preceding diagram Copyright 2012 EnterpriseDB Corporation All rights reserved 45 Postgres Plus xDB Replication Server with Multi Master User s Guide e The publication server to be used is identified by registering its network location user name and password e A publication database definition is created subordinate to the SMR type node under the publication server The Postgres database user name pubuser is specified in the definition along with the database network location and database identifier The publication server creates schema edb replicator pub and populates it with database objects for the replication system s metadata when you create the publication database definition e A publication named pub is created subordinate to the publication database definition The publication consists of table A in schema S1 and tables B and C in schema S2 e The subscription server to be used is identi
52. Snapshot dommrsnapshot For MMR only The dommrsnapshot command performs snapshot synchronization on the specified master node in a multi master replication system dommrsnapshot pubname repsvrfile pubsvrfile pubhostdbid dbid Parameters pubname The name of the publication for which the snapshot is to be taken pubsvrfile The file containing the publication server login information dbid The publication database ID of the target master node for the snapshot replication Examples In the following example snapshot replication is performed on publication emp pub to the target master node identified by publication database ID 9 Copyright 2012 EnterpriseDB Corporation All rights reserved 358 Postgres Plus xDB Replication Server with Multi Master User s Guide java jar edb repcli jar dommrsnapshot emp pub pubhostdbid 9 gt repsvrfile pubsvrfile prop Performing snapshot Source database connectivity info conn jdbc edb 192 168 2 6 5444 edb user pubuser paso vord nA Target database connectivity info conn jdbc edb 192 168 2 7 5444 mmrnode user mmruser password x Connecting with source EnterpriseDB database server Connecting with target EnterpriseDB database server Importing enterprisedb schema edb Table List dept emp Loading Table Data in 8 MB batches Disabling FK constraints amp triggers on edb dept before truncate Truncating table dept before data
53. Subscription count H E EDB DEPT H E EDB EMP Es A Subscription Server 192 168 2 7 9052 tq Replication Servers Figure 178 Selecting a publication for replication history cleanup Step 3 From the Publication menu choose Cleanup Replication History Alternatively click the secondary mouse button on the Publication node and choose Cleanup Replication History The Cleanup Replication History confirmation box appears Copyright 2012 EnterpriseDB Corporation All rights reserved 252 Postgres Plus xDB Replication Server with Multi Master User s Guide Publication Server 192 168 2 7 9051 pa MMR GB sur QW Oracle 192 168 2 6 1521 xe pubu ay sales_ deg EJ EDB Figure 179 Cleaning up replication history Step 4 Click the Yes button in the Cleanup Replication History confirmation box Copyright 2012 EnterpriseDB Corporation All rights reserved 253 Postgres Plus xDB Replication Server with Multi Master User s Guide tq Replication Servers E Publication Server 192 168 2 7 9051 s MMR S sur oa g Subscription Server 192 168 2 7 9052 Figure 180 Cleanup Replication History confirmation Step 5 Click the Yes button in response to Replication History Has Been Removed Copyright 2012 EnterpriseDB Corporation All rights reserved 254 Postgres Plus xDB Replication Server with Multi Master User s Guide Fie Publication Subscription Help 9 UBS OLA s
54. TUE WED THU FRI or SAT This value is case insensitive so Sun and sun will work as well as SUN v month The month of the year This can be any of the following values JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV or DEC This value is case insensitive so Jan and jan will work as well as JAN day of month Copyright 2012 EnterpriseDB Corporation All rights reserved 362 Postgres Plus xDB Replication Server with Multi Master User s Guide The day of the month This can be any integer greater than or equal to 1 and less than or equal to the number of days in month cron expression A cron expression See appendix Section 9 3 3 for information on writing a cron expression Examples In the following example a schedule is created to perform synchronization replication on subscription dept _emp_sub once every 5 minutes java jar edb repcli jar confschedule dept emp sub gt repsvrfile subsvrfile prop gt jobtype t gt realtime 300 Configuring scheduler Job is successfully scheduled In the following example the schedule is removed from subscription dept emp sub java jar edb repcli jar confschedule dept_emp sub gt repsvrfile subsvrfile prop gt remove Configuring scheduler Scheduled job is removed 8 3 37 Configuring a Multi Master Schedule confschedulemmr For MMR only The confschedulemmr command creates a schedule as to when recurri
55. Task Wizard dialog box on a master definition node Step 3 In the Scheduled Task Wizard dialog box select the radio button for either synchronization replication or snapshot replication Note If the publication associated with this subscription is a snapshot only publication then only Snapshot may be chosen Note In a multi master replication system only Synchronize may be chosen Copyright 2012 EnterpriseDB Corporation All rights reserved 224 Postgres Plus xDB Replication Server with Multi Master User s Guide Scheduled Task Wizard Schedule Category Type of Task Synchronize _ Snapshot Perform this task 2 Continuously O Daily C Weekly J Monthly C Cron Expression 5 Back Next gt Cancel Figure 147 Scheduled Task Wizard dialog box Step 4 Select the radio button for the scheduled replication frequency or select Cron Expression to write your own cron expression The frequency choices have the following meanings e Continuously Schedules replication to run continuously at an interval in seconds that you specify Select this option if the source tables change frequently during the day and the target tables must be kept up to date throughout the course of the day e Daily Schedules replication to run once a day at the time you choose Select this option if the target tables need to be refreshed daily e Weekly Schedules replication to run once a day at the time you
56. a delete delete conflict is the removal of a given row and the row in question has already been removed the from the source and target nodes For the earliest timestamp and latest timestamp conflict resolution strategies the transaction timestamp is tracked in a column with data type TIMESTAMP in the shadow table Once selected the conflict resolution strategy for a given table can later be changed to a different strategy see Section 6 8 Copyright 2012 EnterpriseDB Corporation All rights reserved 207 Postgres Plus xDB Replication Server with Multi Master User s Guide 6 6 4 Conflict Prevention Uniqueness Case Since there is no automatic built in resolution strategy for the uniqueness conflict this section discusses strategies to avoid this problem that would be implemented by the DBA This discussion is based on a realm of numeric values generated by a sequence such as for a unique primary key The following are possible strategies e Node specific sequence range A sequence range is reserved for each master node For example master node A would have MINVALUE 1 and MAXVALUI 1000 master node B would have MINVALUE 1001 and MAXVALUE 2000 and so on for other nodes This ensures that a unique ID is always generated across all master nodes e Start value variation Each node is assigned a different start value For example master node A would have a START value of 1 node B would have 2 and node C would
57. accept any changes except from its designated master database This is also known as master to slave replication e Multi Master Replication MMR Two or more databases are designated in which tables with the same table definitions and initial row sets are created Changes inserts updates and deletions to table rows are allowed to occur in any database Changes to table rows in any given database are replicated to their counterpart tables in every other database For a single master replication system a variety of configurations are supported including e Replication between PostgreSQL and Postgres Plus Advanced Server databases between products in either direction e Replication from Oracle to PostgreSQL e Replication in either direction between Oracle and Postgres Plus Advanced Server e Replication in either direction between SQL Server and PostgreSQL e Replication in either direction between SQL Server and Postgres Plus Advanced Server For multi master replication the participating database servers in a given multi master replication system must be of the same type e PostgreSQL database servers e PostgreSQL database servers and Postgres Plus Advanced Servers operating in PostgreSQL compatible mode e Postgres Plus Advanced Servers operating in PostgreSQL compatible mode e Postgres Plus Advanced Servers operating in Oracle compatible mode Note A given database cannot simultaneously participate in both a single master re
58. at the EnterpriseDB website Registration will also give you access to many free assets at EnterpriseDB including PostgreSQL Performance Tuning Bruce Momjian On Demand Webcasts Top 5 Ways to Supercharge your Database On Demand Webcast Data Processing Inside PostgreSQL Bruce Momjian On Demand Webcasts do not have an enterprisedb com user account already have an enterprisedb com user account BitRock Installer Figure 39 Account registration If you do not have an EnterpriseDB user account you will be directed to the registration page of the EnterpriseDB website If you already have an EnterpriseDB user account enter the email address and password for your EnterpriseDB user account as shown in the following screen Click the Next button Copyright 2012 EnterpriseDB Corporation All rights reserved 77 Postgres Plus xDB Replication Server with Multi Master User s Guide EnterpriseDB User Account Information Please enter the email address and password for your enterprisedb com user account Email address user xyz com BitRock Installer lt Back Next gt Cancel Figure 40 My EnterpriseDB account Step 15 Enter the Postgres database connection information for the database server in which the xDB Control database is to run Note From this point on it is suggested that you record the values you enter on these screens as they will be needed during the publicati
59. be entered using uppercase letters for example EDB DEPT and Advanced Server names must be entered in lowercase letters for example edb dept See Section 9 3 5 for additional information on quoted identifiers and case translation Parameters pubname The name of the publication to which tables or views are to be added pubsvrfile The file containing the publication server login information schema tn The name of the schema containing the nth table of the tables parameter list This value is case sensitive table _ n The name of the nth table in the tables parameter list This value is case sensitive schema vn Copyright 2012 EnterpriseDB Corporation All rights reserved 335 Postgres Plus xDB Replication Server with Multi Master User s Guide For SMR only The name of the schema containing the nth view of the views parameter list This value is case sensitive view n For SMR only The name of the nth view in the views parameter list This value is case sensitive ordinal tn For SMR only The ordinal number that is the position in the list counting from left to right starting with 1 of a table in the tables parameter list to which filter clause filter tnis to be applied filter tn For SMR only The filter clause to be applied to the table in the tables parameter list at the position indicated by ordinal tn ordinal vn For SMR only The ordinal number that is the position in the li
60. box appears showing the installation progress of the xDB Replication Server selected components This may take a few minutes Copyright 2012 EnterpriseDB Corporation All rights reserved 83 Postgres Plus xDB Replication Server with Multi Master User s Guide Installing xDB Replication Server Please wait while Setup installs xDB Replication Server on your computer Installing xDB Replication Server Unpacking opt PostgresPlus 9 1AS lib commons collections 3 1jar mass BitRock Installer Figure 46 Installation progress Step 20 When installation has completed the following screen appears Click the Finish button Copyright 2012 EnterpriseDB Corporation All rights reserved 84 Postgres Plus xDB Replication Server with Multi Master User s Guide Completed the xDB Replication Server Setup Wizard EnterpriseDB is the leading provider of value added products and services for the Postgres community Please visit our website at www enterprisedb com PostgreSQL Packaged by Enterprise The Enterprise PostgreSQL Company f Cancel Figure 47 xDB Replication Server installation completion Step 21 On the StackBuilder Plus Installation Complete screen click the Finish button Copyright 2012 EnterpriseDB Corporation All rights reserved 85 Postgres Plus xDB Replication Server with Multi Master User s Guide StackBuilder Plus 2 0 4 Installation Complete Installation of the packages you selecte
61. cannot be replicated e BFILE e BINARY DOUBLE e BINARY FLOAT ILSLABEL e XMLTYPE Oracle tables with the following data types can be used in snapshot only publications but cannot be used in synchronization replications e BLOB e CLOB e LONG e LONG RAW e NCLOB e RAW SQL Server tables that include the following data types cannot be replicated e GEOGRAPHY e GEOMETRY e SQL VARIANT Note See Section 9 3 6 for a method to replicate tables containing the SQL VARIANT data type under certain conditions SQL Server tables with the following data types can be used in snapshot only publications but cannot be used in synchronization replications e BINARY MAGE e NTEXT e NVARCHAR max e TEXT e T ESTAMP e VARBINARY e VARBINARY max Postgres tables with the 1ine geometric data type cannot be replicated Copyright 2012 EnterpriseDB Corporation All rights reserved 54 Postgres Plus xDB Replication Server with Multi Master User s Guide 2 4 4 Performance Considerations This section discusses the processing differences between snapshot and synchronization replications and provides some general guidelines on which method to use 2 4 4 1 What Happens During Snapshot Replication In snapshot replication the target tables are completely reloaded from
62. case translation Parameters pubname The name of the publication containing the table whose conflict resolution strategy is to be updated Copyright 2012 EnterpriseDB Corporation All rights reserved 343 Postgres Plus xDB Replication Server with Multi Master User s Guide pubsvrfile The file containing the publication server login information schema t The name of the schema containing table_name This value is case sensitive table name The name of the table whose conflict resolution strategy is to be updated This value is case sensitive conflictresolution For the conflict resolution option specify E for earliest timestamp conflict resolution L for latest timestamp conflict resolution N for node priority conflict resolution or M for manual conflict resolution standbyconflictresolution For the standby conflict resolution option specify E for earliest timestamp conflict resolution L for latest timestamp conflict resolution N for node priority conflict resolution or M for manual conflict resolution Examples The conflict resolution strategy on Advanced Server table edb emp in publication emp pub is modified to use latest timestamp conflict resolution with a standby strategy of node priority conflict resolution java jar edb repcli jar updateconfresolutionstrategy emp pub gt repsvrfile pubsvrfile prop gt table edb emp gt conflictresolution L stand
63. case sensitive ordinal tn For SMR only The ordinal number that is the position in the list counting from left to right starting with 1 of a table in the tables parameter list to which filter clause filter tnis to be applied filter tn For SMR only The filter clause to be applied to the table in the tables parameter list at the position indicated by ordinal tn ordinal vn For SMR only The ordinal number that is the position in the list counting from left to right starting with 1 of a view in the views parameter list to which filter clause filter _vnis to be applied filter vn For SMR only The filter clause to be applied to the view in the views parameter list at the position indicated by ordinal vn Copyright 2012 EnterpriseDB Corporation All rights reserved 331 Postgres Plus xDB Replication Server with Multi Master User s Guide conflictresolution For time MMR only For the conflict resolution option specify E for earliest stamp conflict resolution L for latest timestamp conflict resolution N for node priority conflict resolution or M for manual conflict resolution The specified conflict resolution applies to the table in the position given by ordinal tn counting from left to right in the tables parameter list If omitted the default is E B standbyconflictresolution For MMR only For the standby conflict resolution option specify E for earliest timestamp conflict resolution
64. changed to the physical database on which the publication was originally defined You must also create the database objects on the former subscription database that xDB Replication Server uses to capture and store updates for replication In order to accomplish the controlled switchover the following tasks must be performed e Optionally move the xDB Control database containing the metadata of the replication system to another host especially if the current xDB Control database host is expected to be taken offline e Modify the xDB Replication Configuration file to reference the new location of the xDB Control database if it is moved e Copy the metadata database objects stored in the publication database shadow tables sequences triggers and a package to the subscription database e Update the replication system metadata in the xDB Control database so as to exchange the connection information for the publication database and subscription database Copyright 2012 EnterpriseDB Corporation All rights reserved 163 Postgres Plus xDB Replication Server with Multi Master User s Guide e Ifa different publication server or subscription server is to be used modify the server locations in the xDB Control database 5 6 2 Controlled Switchover Steps This section describes the steps for performing a controlled switchover The following assumptions are made about the replication system environment e Node 1 is the server where th
65. definitions and most database objects and attributes associated with the publication tables are created in the subscription database by the subscription server If you so choose the same process can automatically occur when a master node is added to a multi master replication system The table definitions and most database objects and attributes associated with the publication tables can be created in the newly added master node by the publication server The following is a list of database objects and table attributes that are replicated from the publication in either a single master or multi master replication system e Tables Views for snapshot only publications created as tables in the subscription database Primary keys Not null constraints Unique constraints Check constraints Indexes Note Foreign key constraints are not replicated by the publication or subscription server in a single master replication system However in a multi master replication system foreign key constraints are replicated from the master definition node to other master nodes xDB Replication Server does have some restrictions on the types of tables it can replicate Copyright 2012 EnterpriseDB Corporation All rights reserved 53 Postgres Plus xDB Replication Server with Multi Master User s Guide Certain types of Oracle partitioned tables can be replicated See Section 9 3 1 4 for details Oracle tables that include the following data types
66. discussed at the end of Section 7 7 1 Step 4 Restart the publication server if the publication server configuration file was modified in Step 3 See Section 5 2 1 for directions on restarting a publication server Step 5 In the database to be used as the new master node create the schema the table definitions and load the tables from your offline data source Step 6 Add the master node as described in Section 6 3 with options Replicate Publication Schema and Perform Initial Snapshot unchecked Step 7 Perform an initial on demand synchronization See Section 6 5 2 for directions on performing an on demand synchronization Step 8 If you are not planning to load any other master nodes using an offline snapshot at this time change the of flineSnapshot option back to false and the batchInitialSync option to true in the publication server configuration file Step 9 Restart the publication server if you modified the publication server configuration file in Step 8 Step 10 Re add the schedule if one had been removed in Step 2 See Section 7 1 for directions on creating a schedule Copyright 2012 EnterpriseDB Corporation All rights reserved 312 Postgres Plus xDB Replication Server with Multi Master User s Guide 8 xDB Replication Server Command Line Interface This chapter discusses the syntax and usage of the xDB Replication Server Command Line Interface CLI This utility program is a command line driven alternative t
67. e Additional entries may be needed in the pg_hba conf files Step 5 If it is necessary to relocate the xDB Control database to another host proceed with this step otherwise go on to Step 7 Create a backup of the xDB Control database and restore it to the Postgres database server on the new host Copyright 2012 EnterpriseDB Corporation All rights reserved 164 Postgres Plus xDB Replication Server with Multi Master User s Guide Update the pg_hba conf file of the database server to allow access to the xDB Control database in accordance with Section 5 1 4 3 Step 6 If you have relocated the xDB Control database in Step 5 update the xDB Replication Configuration file on the hosts where the publication server and subscription server will run to reference the new network location If necessary update the database name user name and password as well For example the following is the original xDB Replication Configuration file user enterprisedb port 5444 password SJ70z8Gk0zY type enterprisedb host 10 90 1 124 database xdb The following is the modified xDB Replication Configuration file with the new network location and authentication information of the xDB Control database user enterprisedb port 5444 password SJ70z8Gk0zY type enterprisedb host 10 90 1 45 database xdb_ sw Step 7 Create a backup of schema edb replicator pub from the publication database on node 1 Restore this backup to the subscription database on
68. ee a Name _edb_replicator_pub nsions Glow patie Schemas 4 edb replicator pub Owner pubuser Fi Collations 0 5 acl pubuser UC pubuser U pubuser Domains 0 Default table ACL fa FTS Configurations 0 Default sequence ACL FTS Dictionaries 0 E Default function ACL 2 FTS Parsers 0 E System schema No iy FTS Templates 0 E Comment m Functions 0 i a A Packages 1 gt Procedures 0 i i amp Sequences 3 a a Tables 12 E rrep_lock E rrep_mmr_pub_group E rrep_mmr_txset E rrep_properties E rrep_publication_subscriptions __ F rrep_publication_tables E rrep_tables E rrep_txset E rrep_txset_health F rrep_txset_log E rrst_edb_dept E rrst_edb_emp t RI Trigger Functions 0 X antl m i es cy S a 3 E H E gt a a E E E ay 4 m Figure 230 Metadata database objects in a Postgres publication database Note The triggers used for synchronization replication do not appear under the Trigger Functions node in pgAdmin Postgres Enterprise Manager Client in Advanced Server because the replication triggers are in Oracle syntax The pgAdmin Trigger Functions node displays only trigger functions which are in PostgreSQL syntax In pgAdmin Oracle triggers appear under the specific table nodes on which the triggers are called Step 4 If the schema that is supposed to contain the metadata database objects the publication d
69. execute jobs in the dbo schema of the msdb database The msdb database is used by SQL Server Agent to schedule alerts and jobs SQL Server Agent runs as a Windows service This example uses the following SQL Server login database users and mappings to comply with the aforementioned rules e The publication tables reside in database edb e The database user owning the schema containing the publication tables and the publication tables themselves is edb e The SQL Server login used by the publication server to connect to SQL Server is pubuser e The database user owning the xDB Replication Server metadata database objects and mapped to SQL Server login pubuser in database edb is pubuser e The schema used to contain the metadata database objects created by the publication server is pubuser e The database user mapped to SQL Server login pubuser in database msdb is pubuser msdb Copyright 2012 EnterpriseDB Corporation All rights reserved 103 Postgres Plus xDB Replication Server with Multi Master User s Guide Note The sqlcmd utility program is used to execute the SQL statements in these examples The USE command establishes the database to which the subsequent statements are to apply The GO command executes the preceding SQL statements as a batch Placement of the GO command within a stream of SQL statements sometimes has significance depending upon the particular SQL statements Step 1 Create a SQL Server login for the xD
70. for an Oracle database The encrypted password is given on the command line with the dbpassword parameter A subscription database ID of 1 is assigned to the database by the subscription server S java jar edb repcli jar addsubdb repsvrfile subsvrfile prop gt Clomypemoracle conoste 92m NOS 2 pom Gio oraiemeles Nm gt dbuser subuser dbpassword ygJ9AxoJEX854elcVIJUPTw gt oraconnectiontype sid database xe Adding Subscription Database Subscription database added successfully Subscription Database id 1 Copyright 2012 EnterpriseDB Corporation All rights reserved 350 Postgres Plus xDB Replication Server with Multi Master User s Guide The following example adds a subscription database definition for an Advanced Server database The encrypted password is read from a file named pwdfile with the dbpassfile parameter A subscription database ID of 2 is assigned to the database by the subscription server S java jar edb repcli jar addsubdb repsvrfile subsvrfile prop gt dbtype enterprisedb dbhost 192 168 2 7 dbport 5444 gt dbuser subuser dbpassfile pwdfile gt database subdb Adding Subscription Database Subscription database added successfully Subscription Database id 2 8 3 27 Printing Subscription Database IDs printsubdbids For SMR only The printsubdbids command prints the subscription database IDs of the subscription database definitions Synopsis printsubdbids r
71. for details on these restrictions e All replication system components must be running in order for replication to occur or before performing any configuration operation or modification in the replication system The xDB Replication Console is used for the configuration and modification of a replication system The xDB Replication Console does not need to be running in order for replication to occur e In general the order of creation of a replication system is as follows 1 Create the required physical databases database user names tables and views to be used in the replication system 2 Define the replication system logical components using the xDB Replication Console or xDB Replication Server CLI 3 Perform replication e In general the order of removal of a single master replication system is as follows 1 Remove the replication system logical components using the xDB Replication Console or xDB Replication Server CLI starting with the subscriptions Subscription nodes and then their parent components Subscription Database nodes 2 Unregister the subscription server if you no longer have any need for it 3 Repeat the same process for the publications 4 After all replication system logical components have been removed except for possibly the publication server and subscription server you can drop any of the physical database objects in Oracle SQL Server or Postgres Do not drop the metadata database objects manually for exa
72. for the null character For example the following combination will replace each null character with the hash symbol replaceNullChar true nullReplacementChar 9 3 1 3 Schema Migration Options Note The option described in this section applies to the subscription server only The option in this section controls how certain aspects of the publication database schema are migrated to the subscription database skipCheckConst By default column CHECK constraints from publication tables are migrated to the subscription table definitions when the subscription is created Set this option to true if you do not want CHECK constraints as part of the subscription table definitions Setting this option to true is useful if the CHECK constraint is based on a built in function supported by the publication database server and this built in function does not exist in the subscription database server skipCheckConst true false The default value is false Copyright 2012 EnterpriseDB Corporation All rights reserved 398 Postgres Plus xDB Replication Server with Multi Master User s Guide 9 3 1 4 Replicating Oracle Partitioned Tables Note The option described in this section must be set to the same value for both the publication server and the subscription server In Oracle table partitioning provides the capability to store table rows in different physical locations tablespaces according to a rule defined on the table
73. in only the master definition node are validated The validation operation does not check if table definitions have changed in other master nodes The following steps show how to validate a single publication Step 1 Make sure the publication server whose node is the parent of the publication you wish to validate is running and has been registered in the xDB Replication Console you are using See Section 5 2 1 for directions on starting and registering a publication server Step 2 For SMR only Select the Publication node of the publication you want to validate Step 2 For MMR only Select the Publication node under the Publication Database node representing the master definition node Copyright 2012 EnterpriseDB Corporation All rights reserved 290 Postgres Plus xDB Replication Server with Multi Master User s Guide Step 3 From the Publication menu choose Validate Publication Alternatively click the secondary mouse button on the Publication node and choose Validate Publication ts Replication Servers ce eS Publication Server 192 168 2 4 9051 Ba sur a Postgres Plus Advanced Server 1 ag sales_dept General Realtime Monitor Replication H Publication schema i a MMR E Subscription Server 1 Validate Publication Cleanup Replication History Cleanup Shadow Table History Figure 215 Validating a selected publication Step 4 If All Schema of Published Tables in Publication pu
74. is created subordinate to the publication database definition The publication consists of table A in schema S1 and tables B and C in schema S2 e A second master node is added by creating another publication database definition subordinate to the MMR type node of the publication server under which the master definition node resides The Postgres database user name mmruser_b is specified in the definition along with the database network location and database identifier to create the second master node e When you add the second master node you can choose to have the publication server create schemas S1 and S2 and the table definitions for A B and C for you or you could have manually created the schemas and table definitions beforehand The publication server creates schema edb replicator pub under which it creates the database objects to store the master node s metadata When defining the master node you can choose to have the publication server populate these tables with rows from the publication at this time or you can defer table loading to a later point in time e A third master node is added in a similar manner using the Postgres database user name mmruser C The following screen capture shows how the logical components of this replication system appear in the xDB Replication Console replication tree Copyright 2012 EnterpriseDB Corporation All rights reserved 49 Postgres Plus xDB Replication Server with Multi Master User
75. more than one computer is used to host the components of the replication system each computer must be able to communicate with the others on a network There are a number of different aspects to this topic e Fora discussion of firewalls see Section 5 1 4 1 e Fora discussion of network IP addresses see Section 5 1 4 2 A Postgres database server uses the host based authentication file pg _hba conf to control access to the databases in the database server You need to modify the pg_hba conf file in the following locations e On the Postgres database server that contains the xDB Control database e Oneach Postgres database server that contains a master node In a default Postgres installation this file is located in the directory POSTGRES INSTALL HOME data The modifications needed to the pg_hba conf file for each of the aforementioned cases are discussed in the following sections xDB Control Database On the database server on which the xDB Control database resides the following entry must be added to allow access to the xDB Control database host control dbname control_dbuser pub _ipaddr 32 md5 Copyright 2012 EnterpriseDB Corporation All rights reserved 180 Postgres Plus xDB Replication Server with Multi Master User s Guide The values you substitute for control_dbname and control dbuser are the entries for fields database and user in the xDB Replication Configuration file found on the host running the publication se
76. network There are a number of different aspects of this topic as discussed in the following sections 5 1 4 1 Firewalls Verify that the firewalls on the hosts allow access from the other hosts running replication system components Refer to the directions for your host s operating system to enable accessibility 5 1 4 2 Network IP Addresses When configuring a replication system you must supply the network location of various components such as the publication server subscription server publication database server and subscription database server This information consisting of the component s IP address and port number is stored as part of the replication system s metadata When one component needs to access another it refers to the network location in the metadata that you supply during configuration Copyright 2012 EnterpriseDB Corporation All rights reserved 110 Postgres Plus xDB Replication Server with Multi Master User s Guide During replication system configuration it is strongly suggested that you supply the actual network IP address of each component and avoid the usage of the loopback address localhost or 127 x x x even if all components are running on the same host You can obtain the network IP address using the following command For Linux only Use the sbin ifconfig command For Windows only Open a Command Prompt window and use the ipconfig command The loopback address works as long as the co
77. node of a multi master replication system e Modifies the insert update delete triggers that add data into the shadow table whenever a transaction occurs on the target table e Modifies the shadow table to properly accommodate the target table changes Note Currently the DDL change replication feature supports only the addition of new columns to a table The syntax of the ALTER TABLE statement that can be used is as follows ALTER TABLE schema table name ADD COLUMN column_name data_type DEFAULT dflt_expr column constraint 1 column constraint 2 The following restrictions apply to the ALTER TABLE statements contained in the text file e Each ALTER TABLE statement in the text file must be terminated by a semicolon and begin on a separate line e There may be only one ADD COLUMN clause per ALTER TABLE statement e Within a given text file the target table of all ALTER TABLE statements must be the same Copyright 2012 EnterpriseDB Corporation All rights reserved 302 Postgres Plus xDB Replication Server with Multi Master User s Guide Parameters schema The name of the schema containing table_name This value is case sensitive table name The name of the table to which the column is to be added This value is case sensitive column name The name of the column to be added data type The data type of the new colu
78. node 2 that is to become the new publication database Step 8 Create a backup of the replication triggers on the publication tables on node 1 These triggers are named with prefixes of rrpd_ rrpi_ and rrpu_ Restore these triggers to the new publication database on node 2 Delete or disable these triggers on node 1 Step 9 Update the metadata in the xDB Control database so that the publication database definition references the new publication database that is the former subscription database on node 2 and the subscription database definition references the new subscription database that is the former publication database on node 1 The connection information that may require updating includes the following e Host IP address e Port number e User name e Password Copyright 2012 EnterpriseDB Corporation All rights reserved 165 Postgres Plus xDB Replication Server with Multi Master User s Guide The following shows the update to the publication database definition so that its network IP address is now node 2 192 168 10 103 WILDS Celle Rejoliesieoir IPUNE re pipu CliccloesS Sit clo Iiose VIA Ios IOS The following shows the update to the subscription database definition so that its network IP address is now node 1 192 168 10 102 UPDATE edb uc oiniccie Orsi nenepmSUbmECdiedbas cm SOMO sic mene Zeer ORM OZ I Step 10 If you decide to use a publication server or subscription server on a n
79. problem with the replication system metadata Perform the operation described in Section 9 2 4 2 Database cannot be removed Reason Publication service failed to clean up replication control schema tables Resolution The metadata database objects under the Oracle publication database user schema or under the Postgres schema edb replicator pub cannot be deleted by the publication server The metadata database objects or schema may have already been deleted The publication database definition cannot be removed using the xDB Replication Console Perform the operation described in Section 9 2 4 2 Database connection cannot be added Cannot register database because it is already registered by a publication service Resolution A given Oracle database can be specified in a publication database definition only once with a given network location and user name An Oracle database can be used multiple times if different Oracle user names are used for each publication database definition A given Postgres database can be specified in a publication database definition only once with a given network location Database connection cannot be added Publication database connection registration failed Reason IO exception The Network Adapter could not establish the connection Resolution Verify that the database server is running For Oracle verify that the Oracle listener program 1snrct1 is running Database connection cannot be added The u
80. replication The following definitions are used when referring to multi master replication systems A master node is a database participating in a multi master replication system The database master node in which the publication is initially defined is specially designated as the master definition node There can be only one master definition node at any given time however it is possible to change which master node is the master definition node The master definition node has the following significance Copyright 2012 EnterpriseDB Corporation All rights reserved 20 Postgres Plus xDB Replication Server with Multi Master User s Guide e The publication is initially created in the master definition node and the tables comprising the publication must exist in the database to be designated as the master definition node at the time the publication is defined e The publication can be initially replicated to other master nodes by means of a snapshot from the master definition node e Each subsequent master node added to the replication system must either 1 contain no tables with the same schema qualified names as the publication tables in the master definition node or 2 contain all publication table definitions as they exist in the master definition node with the same schema qualified names In the first case when you add the master node you select the option to replicate the publication schema from the master definition node In
81. s Guide FS ay Console Subscription Help OSU Os ig Sl g Replication Servers as oe Publication Server 192 168 10 104 9051 Postgres Plus Advanced Server 192 168 10 104 5444 mmrnode_a mmruser_a MDN ty pub s1 a H E s2 b EE s2 c G R Postgres Plus Advanced Server 192 163 10 104 5444 mmrnode_b mmruser_b pub H E st a 2 b EE s2 c j P Postgres Plus Advanced Server 192 168 10 107 5444 mmrnode_c mmruser_c B y pub H E st a Figure 20 Postgres multi master replication tree See Chapter 4 for an introduction to the xDB Replication Console 2 4 Designing a Replication System This section presents the general steps design considerations and best practices for designing a replication system before you begin the actual implementation 2 4 1 General Steps The following steps provide a general guideline for implementing a replication system Step 1 Determine if xDB Replication Server is the right solution for your requirements and you have chosen the best solution for your particular needs xDB Replication Server can be used to implement single master or multi master replication systems For single master replication systems the distinguishing characteristic of xDB Replication Server is its ability to replicate from an Oracle database to a PostgreSQL or Advanced Server database from a SQL Server database to a PostgreSQL or Advanced Server database Copyright 2012 EnterpriseDB Corporation All righ
82. subscription for Postgres Plus xDB Replication Server Figure 51 Product Registration dialog box Copyright 2012 EnterpriseDB Corporation All rights reserved 89 Postgres Plus xDB Replication Server with Multi Master User s Guide Step 4 If Registered Successfully appears click the OK button otherwise verify you have entered the correct information Contact EnterpriseDB if you are still having difficulty Figure 52 Successful product registration The updated status of your product appears in the bottom right hand corner of the xDB Replication Console Figure 53 Updated registration status Copyright 2012 EnterpriseDB Corporation All rights reserved 90 Postgres Plus xDB Replication Server with Multi Master User s Guide Copyright 2012 EnterpriseDB Corporation All rights reserved 91 Postgres Plus xDB Replication Server with Multi Master User s Guide 4 Introduction to the xDB Replication Console The xDB Replication Console is the graphical user interface that you use to configure and manage the replication system The equivalent functionality can also be done using the xDB Replication Server CLI utility See Chapter 8 for information on the xDB Replication Server CLI The xDB Replication Console window consists of the following main areas e Menu Bar Menus for the replication system components e Tool Bar Icons for quick access to dialog boxes e Replication Tree Replicatio
83. subscription tables For a SQL Server publication database If the schema containing the publication tables and views in SQL Server is named dbo then the subscription server creates a schema named dbo sql in the Postgres subscription database for the subscription tables Schema dbo is a special reserved schema in Postgres The existing schemas must not contain any tables or views with the same names as the publication tables and views The subscription server returns an error if there are already identically named tables or views You must delete or rename these tables and views before the subscription can be created A new subscription database owned by the subscription database user subuser can be created with the following CREATE DATABASE subdb OWNER subuser 5 1 3 2 Oracle Subscription Database Step 1 Optional If you do not have an existing database that you want to use as your subscription database create a new database This step can be fairly complicated Refer to the appropriate Oracle documentation for performing this task Copyright 2012 EnterpriseDB Corporation All rights reserved 108 Postgres Plus xDB Replication Server with Multi Master User s Guide Step 2 Create a database user name for the subscription database user The subscription database user name must have a password and it must have the ability to create a database session The subscription database user becomes the owner of the replica
84. sys schemas s 5 gt WHERE s name edb 6 gt AND o type TR 1S AND o name LIKE rr 8 gt AND o schema_id s schema_id g gt ORDERTBY TIF 10 gt GO Trigger Name ecdbrrrpdmedomcdepir edb rrpd_ edb emp Clo wizjsul siels _Cksjone Selon izes sels iis ecb eer pumediomcepis edberEpumedoyemp 6 rows affected Finally some jobs are created in the msdb database as shown by the following 1 gt USE msdb 2 gt GO Changed database context to msdb 1 gt 2 gt SELECT j name Job Name 3S FROM msdb dbo sysjobs j 4 gt master dbo syslogins 1 WHERE l name pubuser 6 gt AND j name LIKE rrep T AND j owner sid a 8 gt ORDERS BY 7 9 gt GO Job Name rrep cleanup job edb AO IDS Joo clo 2 rows affected For Postgres only The metadata database objects are created in the schema _edb replicator pub as shown in the following Copyright 2012 EnterpriseDB Corporation All rights reserved 129 Postgres Plus xDB Replication Server with Multi Master User s Guide Ez File Edit Plugins View Management Tools Help a S SQL i v ABook ELO BRF GIO OE l Properties x Statistics Dependencies Depende H Databases 3 _ Property Value gt Catalogs 5 5 g Extensions 4 p Sang o b Sh 9 PET Owner pubuser IFA Collations 0 Eaa pubuser UC pubuser U pubuser Domains 0 Default ta
85. tables Note For SMR Only The replication history can be viewed from the Publication node as well as from the Subscription node The history shown for a Publication node is actually the exact same set of inserts updates and deletions made on the subscription tables by the publication server during synchronization The history shown for a Publication node does not show the actual SQL statements processed on the publication tables that originated from user applications Note For MMR only The replication history can be viewed from the Publication node under any master node in the multi master replication system The history shown includes inserts updates and deletions made on all publication tables of all master nodes by the publication server during synchronization and hence the history appears the same regardless of the master node under which the history is viewed 7 3 1 All Replication History Replication history shows the following types of events that occur on a given subscription or master node e Snapshot replications e Synchronization replications where at least one change insert update or deletion was applied to a target table e Synchronization replications where no updates were applied to any of the target tables since the last restart of the publication server The following steps describe how to view the replication history of the events in the preceding list Step 1 For SMR only Select the node beneath the Su
86. the Publication menu choose Publication Database and then choose Add Database Alternatively click the secondary mouse button on the SMR type node and choose Add Database The Publication Service Add Database dialog box appears Step 3 Fill in the following fields e Database Type Select Oracle SQL Server PostgreSQL or Postgres Plus Advanced Server for the type of publication database For an Advanced Server Oracle compatible installation select the Postgres Plus Advanced Server option For an Advanced Server PostgreSQL compatible installation select the PostgreSQL option Host IP address of the host on which the publication database server is running Port Port on which the publication database server is listening for connections User The publication database user name created in Step 1 of Section 5 1 2 Password Password of the database user Service ID For Oracle Enter the Oracle System Identifier SID of the Oracle instance running the publication database if the SID radio button is selected Enter the net service name of a connect descriptor as defined in the TNSNAMES ORA file if the Service Name radio button is selected e Database For Postgres or SQL Server Enter the Postgres or SQL Server database name Copyright 2012 EnterpriseDB Corporation All rights reserved 121 Postgres Plus xDB Replication Server with Multi Master User s Guide Publication Service Add Dat Please specify Oracle database in
87. the lock is not released before then If ddlChangeTableLock is set to false an exclusive table lock is not requested e The DDL statement is executed against the target table The replication triggers and shadow table are modified accordingly If an error occurs the user is informed and the operation is aborted If dd1ChangeTableLock is set to true the exclusive lock is released e The preceding two bullet points are repeated on the target table for each database in the replication system e The in memory table metadata definition is refreshed to reflect the DDL change The user is informed of successful completion of the operation e If an error occurs during the prior steps any changes up to that point are rolled back so that the publication table replication triggers and shadow table are reverted back to their original state prior to the start of this operation If one or more databases goes down before completion of the operation the publication is marked as dirty to avoid further replication events Copyright 2012 EnterpriseDB Corporation All rights reserved 304 Postgres Plus xDB Replication Server with Multi Master User s Guide The following section describes how to initiate DDL change replication using the xDB Replication Console 7 6 2 DDL Change Replication Using the xDB Replication Console DDL change replication can be applied using the xDB Replication Console as follows Step 1 Prepare the text file
88. the xDB Control database where the metadata database objects are to be deleted All replication systems running subordinate to the publication server and subscription server must then be recreated following the directions in sections 5 2 onward Warning Do not attempt this if any replication systems are running in production All replication systems using the affected publication server and subscription server will become inoperable Copyright 2012 EnterpriseDB Corporation All rights reserved 385 Postgres Plus xDB Replication Server with Multi Master User s Guide This section describes what to look for in order to tell if the metadata is not complete and if so what must be deleted to completely remove the replication system This section does not discuss the internal contents of the metadata tables If all of the database objects comprising the metadata are present then review the checklist in Section 9 2 3 before proceeding with deletion of the metadata as it is fairly unlikely that the content of a metadata table becomes corrupted If you decide that you must delete all of the metadata database objects follow the steps as discussed in the following Step 1 Stop the publication server Step 2 Stop the subscription server Step 3 Look for the metadata database objects contained within a publication database In the example used in this section pubuser is the publication database user name The publication consists of two t
89. then choose Update Database Alternatively click the secondary mouse button on the Publication Database node and choose Update Database The Update Database Source dialog box appears Step 5 Enter the desired changes See Step 3 of Section 5 2 2 for the precise meanings of the fields for a single master replication system See sections 6 2 2 and 6 3 for a multi master replication system Database Type Oracle Oracle Database Information Please specify Oracle database information Database 192 168 2 6 1521 xe pubuser Host 192 168 2 6 Port 1521 User pubuser Password eseeesee Service ID xe SID Service Name et seve cance Figure 190 Update Database Source dialog box for a single master replication system Copyright 2012 EnterpriseDB Corporation All rights reserved 264 Postgres Plus xDB Replication Server with Multi Master User s Guide Step 6 Click the Test button If Test Result Success appears click the OK button then click the Save button Figure 191 Successful publication database test If an error message appears investigate the cause of the error correct the problem and repeat steps 1 through 6 Step 7 Restart the publication server See Section 5 2 1 for directions on restarting the publication server Step 8 Click the Refresh icon in the xDB Replication Console tool bar to show the updated Publication Databa
90. to generate the encrypted form of a password See Chapter 3 for information on how the initial content of the xDB Replication Configuration file is determined See Section 3 2 for the file system location of the xDB Replication Configuration file 2 3 1 5 xDB Replication Console The xDB Replication Console is the graphical user interface program you can use to create and control all aspects of a replication system Through a single xDB Replication Console you can configure and operate a replication system running on the same host on which the xDB Replication Console is installed or you can configure and operate replication systems where the xDB Replication Server components are distributed on different hosts in a networked environment Copyright 2012 EnterpriseDB Corporation All rights reserved 30 Postgres Plus xDB Replication Server with Multi Master User s Guide ost B xDB Replication Console or xDB Replication Console or xDB Replication Server CLI xDB Replication Server CLI XDB Replication Server oA e Confi xen g Shen Servi Server ____ Metadata e B opaca lt a T Tate Ce cans Bol ime Publication axe Ay entears Figure 10 xDB Replication Consoles accessing multiple hosts In the preceding figure there are two Postgres installations running on two networked hosts each with its own xDB Replication Server installation Each host is running a pu
91. updates and deletions to the rows in the source tables since the last replication are applied to the target tables In a single master replication system the very first replication to a newly created subscription must always be done by a snapshot Subsequent replications can be done by snapshot or by synchronization provided that the publication is not defined as a snapshot only publication as discussed in Section 2 2 7 In a multi master replication system the very first replication from the master definition node to a newly added master node is done by a snapshot Subsequent replications between master nodes occur by synchronization However it is possible to perform subsequent snapshots from the master definition node to any other master node See Section 2 4 4 for a discussion of the advantages and disadvantages of each method 2 2 7 Snapshot Only Publications When a publication is created in a single master replication system the publication can be defined as a snapshot only publication Replication from a snapshot only publication can only be done using the snapshot replication method Synchronization replication is not permitted on a snapshot only publication A snapshot only publication cannot be created in a multi master replication system See Section 2 4 4 for a discussion of the advantages of using a snapshot only publication 2 2 8 Filters A filter specifies a subset of rows in a publication table or view that is to be inclu
92. values literals etc A term s exact meaning depends upon the context in which it is used e Italic font introduces a new term typically in the sentence that defines it for the first time e Fixed width mono spaced font is used for terms that must be given literally such as SQL commands specific table and column names used in the examples programming language keywords etc For example SELECT FROM emp e Italic fixed width font is used for terms for which the user must substitute values in actual usage For example DELETE FROM table name Copyright 2012 EnterpriseDB Corporation All rights reserved 10 Postgres Plus xDB Replication Server with Multi Master User s Guide A vertical pipe denotes a choice between the terms on either side of the pipe A vertical pipe is used to separate two or more alternative terms within square brackets optional choices or braces one mandatory choice Square brackets denote that one or none of the enclosed terms may be substituted For example a b means choose one of a or b or neither of the two Braces denote that exactly one of the enclosed alternatives must be specified For example a b means exactly one of a or b must be specified Ellipses denote that the preceding term may be repeated For example a b means that you may have the sequence b a a b a 1 2 Other Conventions Used in this Guide
93. within the publication database definition identified by publication database ID 1 S java jar edb repcli jar confcleanupjob 1 gt repsvrfile pubsvrfile prop gt enable hourly 3 Configuring cleanup job Cleanup job configured In the following example shadow table history cleanup is scheduled to run once a day at 6 00 PM on the shadow tables created within the publication database definition identified by publication database ID 1 S java jar edb repcli jar confcleanupjob 1 gt repsvrfile pubsvrfile prop enable daily 18 Contigueimno eleanup Job an Cleanup job configured In the following example shadow table history cleanup is scheduled to run every Wednesday at 8 00 AM on the shadow tables created within the publication database definition identified by publication database ID 1 S java jar edb repcli jar confcleanupjob 1 gt repsvrfile pubsvrfile prop gt enable weekly WEDNESDAY 8 Con Bigumimegseleanupma Obmrrn Cleanup job configured In the following example the shadow table history cleanup job is disabled on the publication database definition identified by publication database ID 1 S java jar edb repcli jar confcleanupjob 1 gt repsvrfile pubsvrfile prop disable Configuring cleanup Job nk Cleanup job removed 8 3 42 Cleaning Up Shadow Table History cleanshadowhistforpub The cleanshadowhistforpub command deletes the shadow table history for the sp
94. xDB Replication Server including basic replication concepts and definitions architecture and components of xDB Replication Server and design guidelines for setting up a replication system e Chapter 3 gives instructions for installing xDB Replication Server e Chapter 4 provides an overview of the xDB Replication Console the graphical user interface for using xDB Replication Server e Chapter 5 gives instructions for the configuration and operation of xDB Replication Server for single master replication systems e Chapter 6 gives instructions for the configuration and operation of xDB Replication Server for multi master replication systems e Chapter 7 describes operations that are common to both single master and multi master replication systems e Chapter 8 describes the xDB Replication Server Command Line Interface an alternative to the graphical user interface for xDB Replication Server configuration and management e Chapter 9 is an appendix containing troubleshooting tips a list of error messages their causes and resolutions and miscellaneous technical information 1 1 Typographical Conventions Used in this Guide Certain typographical conventions are used in this manual to clarify the meaning and usage of various commands statements programs examples etc This section provides a summary of these conventions In the following descriptions a term refers to any word or group of words that are language keywords user supplied
95. 1 a SMR Property ij B MMR Service status Running Authentication Passed Publication database count 0 Figure 66 Replication tree after registering a publication server Continue to build the single master replication system under the SMR type node 5 2 2 Adding a Publication Database The database in which publications are to reside must be identified to xDB Replication Server This is done by creating a publication database definition After the publication database definition is created a Publication Database node representing that publication database definition appears in the replication tree of the Copyright 2012 EnterpriseDB Corporation All rights reserved 120 Postgres Plus xDB Replication Server with Multi Master User s Guide xDB Replication Console Publications that are to contain tables and views residing within this database can then be created under the Publication Database node You must enter database connection information such as the database server network address database identifier and database login user name and password when you create the publication database definition The connection information is used by the publication server to access the publication tables and views when it performs replication Step 1 Make sure the database server in which the publication database resides is running and accepting client connections Step 2 Select the SMR type node under the Publication Server node From
96. 13 46 Success 0 084 Secs 3 Synchronize 2012 06 07 11 10 31 Success 0 029 Secs 3 Synchronize 2012 06 07 11 09 26 Success 0 092 Secs 1 Synchronize 2012 06 07 11 08 57 Success 0 385 Secs 2 Synchronize 2012 06 07 10 18 48 Success 4 789 Secs 7 Snapshot 2012 06 06 16 46 55 Success 4 373 Secs 7 Snapshot V Show history with transactions count gt O Figure 165 Setting replication history to hide zero transaction count records Step 2 The next time the Replication History tab refreshes only the replications with non zero transaction counts appear in the Replication History Note e Hiding of zero transaction count replication records stays in effect only while viewing the Replication History tab after checking the Show History With Transactions Count gt 0 check box If you change the focus in the replication tree Copyright 2012 EnterpriseDB Corporation All rights reserved 239 Postgres Plus xDB Replication Server with Multi Master User s Guide to another node zero transaction count records reappear on the Replication History tab when you come back to it e Zero transaction count replication records are maintained in the publication server memory They are not permanently stored on disk Therefore when the publication server is shut down the in memory zero transaction count replication records are no longer available When the publication server starts running again zero transaction count replication records will ap
97. 192 D General Realtime Monitor Replication H Publication schema Table count Subscription count Figure 220 Selecting a publication to remove Step 3 Remove the publication in any of the following ways e Choose Remove Publication from the Publication menu e Click the secondary mouse button on the Publication node and choose Remove Publication e Click the primary mouse button on the Remove Publication icon Copyright 2012 EnterpriseDB Corporation All rights reserved 296 Postgres Plus xDB Replication Server with Multi Master User s Guide Publication Server 192 168 2 7 9051 BW Oracle 192 168 2 6 1521xe pubu sales_d ar Figure 221 Removing the publication using the menu bar Step 4 In the Remove Publication confirmation box click the Yes button Copyright 2012 EnterpriseDB Corporation All rights reserved 297 Postgres Plus xDB Replication Server with Multi Master User s Guide g Replication Servers amp S Publication Server 192 168 2 7 9051 84 sur Ki Oracle 192 168 2 6 1521 xe pubus Publication schema Table count 2 Subscription count 0 H E EDB DEPT EE EDB EMP joo MMR B Subscription Server 192 168 2 7 9052 R Postgres Plus Advanced Server 192 1 Remove Publication Q Do you really want to remove publication sales_dep Figure 222 Remove Publication confirmation The Publication node no longer ap
98. 192 168 2 7 9051 i g Subscription Server 192 168 2 7 9052 Postgres Plus Advanced Server 192 1 Figure 107 Replication tree after removing a subscription 5 5 5 Removing a Subscription Database Deleting a subscription database definition from xDB Replication Server is equivalent to removing its Subscription Database node Before a Subscription Database node can be removed all subscriptions under that Subscription Database node must be removed See Section 5 5 4 for removing a subscription Removing a Subscription Database node does not delete the physical database from the database server It removes the identity and association of the database to xDB Replication Server so no further replications can create or update tables in the database unless there are other subscription database definitions in xDB Replication Server with the same host and database identifier The physical database can only be removed using the database management system s database removal procedures Step 1 Make sure the subscription server whose node is the parent of the subscription database definition you wish to remove is running and has been registered in the xDB Replication Console you are using See Section 5 3 1 for directions on starting and registering a subscription server Step 2 Select the Subscription Database node that you wish to remove Copyright 2012 EnterpriseDB Corporation All rights reserved 160 Postgres Plus xDB Replicati
99. 3 2 Encrypting the Password in the xDB Replication Configuration File If you need to change the password in the xDB Replication Configuration file you must first encrypt the password Use the encrypt command of the xDB Replication Server CLI to generate the encrypted form of the password from its plain text form given in an input file Step 1 Create a text file with the password you wish to encrypt Do not leave any white space before or after the password The following example shows the text newpassword in the input file passfile o cat passille newpassword Step 2 Use the edb repcli jar file to execute the xDB Replication Server CLI with the encrypt command as shown by the following export PATH opt PostgresPlus 9 1AS jre bin PATH Copyright 2012 EnterpriseDB Corporation All rights reserved 403 Postgres Plus xDB Replication Server with Multi Master User s Guide cd opt PostgresPlus 9 1AS bin S java jar edb repeli jar encrypt input passfile output encrypted The following shows the encrypted form of the password in the output file encrypted cat encrypted 4mKq 4jQQoV2IypCSmPpTQ Step 3 Copy and paste the encrypted password into the xDB Replication Configuration file user enterprisedb port 5444 password 4mKq 4 QQo0V21ypCSmPpTQ type enterprisedb host localhost database xdb 9 3 3 Writing a Cron Expression A cron expression is a text string used to express a schedule of dates an
100. 52 R Postgres Plus Advanced Server 192 1 Publication schema Table count Subscription count Figure 193 Selecting a publication to which to add tables Step 3 Open the Add Tables dialog box in any of the following ways e From the Publication menu choose Update Publication then Add Tables e Click the secondary mouse button on the Publication node choose Update Publication and then choose Add Tables e Click the primary mouse button on the Add Publication Tables icon Copyright 2012 EnterpriseDB Corporation All rights reserved 268 Postgres Plus xDB Replication Server with Multi Master User s Guide ta Replication Servers ce Publication Server 192 168 2 7 9051 Ba sure w Oracle 192 168 2 6 1521 xe pubu Update Publication sof MMR S E Subscription Server oe R Postgres Plus Ad Cleanup Replication History Cleanup Shadow Table History Figure 194 Opening the Add Tables dialog box Step 4 Fill in the following fields in the Add Tables tab of the Add Tables dialog box e Add Check the boxes next to the table names from the Available Tables list that are to be added to the publication If the publication is a snapshot only publication then views would appear in the Available Tables list as well The Available Tables list contains only tables and views that are not already members of other publications under the same Publication Database node e Select All Check this box if you want to inc
101. 8 Success 0 036 Secs 2 Synchronize 2012 06 07 11 24 28 Success 0 011 Secs 0 Synchronize 2012 06 07 11 24 08 Success 0 0090 Secs 0 Synchronize 2012 06 07 11 23 48 Success 0 081 Secs 2 Synchronize 2012 06 07 11 23 28 Success 0 01 Secs 0 Synchronize 2012 06 07 11 23 08 Success 0 028 Secs 0 Synchronize 2012 06 07 11 13 46 Success 0 084 Secs 3 Synchronize 2012 06 07 11 11 48 Success 0 034 Secs 0 Synchronize 2012 06 07 11 10 31 Success 0 029 Secs 3 Synchronize 2012 06 07 11 09 26 Success 0 092 Secs 1 Synchronize 2012 06 07 11 08 57 Success 0 385 Secs 2 Synchronize 2012 06 07 10 18 53 Success 0 069 Secs 0 Synchronize 2012 06 07 10 18 48 Success 4 789 Secs 7 Snapshot 2012 06 06 16 46 55 Success 4 373 Secs 7 Snapshot Figure 164 Replication history with zero transaction counts While viewing the Replication History tab you can hide the records with zero transaction counts as follows Copyright 2012 EnterpriseDB Corporation All rights reserved 238 Postgres Plus xDB Replication Server with Multi Master User s Guide Step 1 Check the Show History With Transactions Count gt 0 check box located at the bottom of the Replication History tab A General Realtime Monitor Replication History Start time Status Duration TX count Type 2012 06 07 11 27 08 Success 0 061 Secs 1 Synchronize 2012 06 07 11 24 48 Success 0 036 Secs 2 Synchronize 2012 06 07 11 23 48 Success 0 081 Secs 2 Synchronize 2012 06 07 11
102. B Replication Server publication database user The login must have a password When creating the publication database definition the SQL Server login is entered in the Publication Service Add Database dialog box see Section 5 2 2 USE master GO CREATE LOGIN pubuser WITH PASSWORD password GO Step 2 Create the database user and its required privileges for job scheduling in database msdb USE msdb CREATE USER pubuser msdb FOR LOGIN pubuser GRANT EXECUTE ON SCHEMA dbo TO pubuser msdb GRANT SELECT ON SCHEMA dbo TO pubuser_ msdb Step 3 Create the database user for xDB Replication Server metadata database object creation and ownership The metadata database objects are created in the publication database to track control and record the replication process and history This example assumes the metadata database objects are to be created in a schema named pubuser USE edb GO CREATE USER pubuser FOR LOGIN pubuser WITH DEFAULT SCHEMA pubuser Note The remaining steps assume that the commands are given in the publication database that is the USE edb command has been previously given to establish the publication database edb as the current database Step 4 Grant the database level privileges needed by the publication database user to create the xDB Replication Server metadata database objects GRANT CREATE TA
103. BLE TO pubuser GRANT CREATE PROCEDURE TO pubuser GO Step 5 Choose the schema where the xDB Replication Server metadata database objects are to reside Copyright 2012 EnterpriseDB Corporation All rights reserved 104 Postgres Plus xDB Replication Server with Multi Master User s Guide To create the metadata database objects in a new schema owned by the publication database user and created exclusively for this purpose recommended approach issue the following command CREATE SCHEMA pubuser AUTHORIZATION pubuser GO Alternatively to create the metadata database objects in an existing schema such as in the same schema containing the publication tables use the following commands GRANT ALTER ON SCHEMA edb TO pubuser GRANT EXECUTE ON SCHEMA edb TO pubuser GRANT SELECT ON SCHEMA edb TO pubuser GRANT INSERT ON SCHEMA edb TO pubuser GRANT UPDATE ON SCHEMA edb TO pubuser GRANT DELETE ON SCHEMA edb TO pubuser GO Step 6 Grant the privileges required to create triggers on the publication tables The publication database user must have the ALTER privilege on the publication tables GRANT ALTER ON edb dept TO pubuser GRANT ALTER ON edb emp TO pubuser GRANT ALTER ON edb jobhist TO pubuser GO Step 7 The publication database user must be able to read the tables and views that are to be included in publi
104. CREATE ANY TRIGGER privileges See Section 5 1 2 1 For a SQL Server publication database verify the following e Inthe msdb database verify that the database user mapped to the SQL Server login given in the publication database definition has EXECUTE and SELECT privileges on schema dbo e In the publication database verify that the database user mapped to the SQL Server login given in the publication database definition has its default schema set to the schema containing the xDB Replication Server metadata database objects e For the same database user discussed in the prior paragraph verify that this database user is either the owner of the schema containing the xDB Replication Server metadata database objects or has the following privileges on this schema ALTER EXECUTE SELECT INSERT UPDATE and DELETE e For the same database user discussed in the prior paragraph verify that this database user has CREATE TABLE and CREATE PROCEDURE privileges e For the same database user discussed in the prior paragraph verify that this database user has ALTER privilege on the publication tables e For any database user that will be updating the publication tables verify that these database users have EXECUTE SELECT and INSERT privileges on the schema containing the xDB Replication Server metadata database objects
105. Count SQL STORED PROCEDURE pubuser JobCleanup SQL STORED PROCEDURE pubuser JobCreateTxSet SQL STORED PROCEDURE pubuser LoadPubTableList SQL STORED PROCEDURE pubuser nextval SQL STORED PROCEDURE pubuser RemoveCleanupJob SQL STORED PROCEDURE pubuser RemoveCreateTxSetJob SQL STORED PROCEDURE pubuser sp createsequence SQL STORED PROCEDURE pubuser sp dropsequence SQL STORED PROCEDURE pubuser rrep common seq USER_TABLE pubuser rrep lock USER TABLE pubuser rrep mmr pub group USER TABLE pubuser rrep mmr txset USER _TABLE UUOVISSie IASIO JOOS SIcIe S s USER TABLE pubuser rrep publication subscriptions USER TABLE pubUseryerepe pub laicatlon edocs USER TABLE pubuser rrep tables USER TABLE pubu user Ere OE Eseg USER_TABLE pubuser rrep exset USER TABLE pubusertr repito etehealieh USER TABLE pubusex neep txset log USER TABLE pu ubu user rrep Exset seg USER TABLE pubusexn rrse edb dept USER TABLE pubuser rrst_edb_ emp USER TABLE 31 rows affected Copyright 2012 EnterpriseDB Corporation All rights reserved 128 Postgres Plus xDB Replication Server with Multi Master User s Guide For non snapshot only publication tables triggers are created that reside in the schema containing the publication tables as shown by the following 1 gt USE edb 2 CO Changed database context to edb is 2 gt SELECT s name o name Trigger Name 3 gt FROM sys objects o 4 gt
106. E Postgres Plus Advanced Server 1 Figure 144 Selecting the master definition node on which to set a schedule Step 2 For SMR only Open the Scheduled Task Wizard dialog box in any of the following ways e From the Subscription menu choose Schedule then Configure Schedule e Click the secondary mouse button on the Subscription node and choose Configure Schedule e Click the primary mouse button on the Configure Schedule icon ME LDB Replication Conse File Publication bd Replication Se H E Pubiicatio Subscript B Postg ESI E Publication server Publication server port Schedule Figure 145 Opening the Scheduled Task Wizard dialog box on a subscription Copyright 2012 EnterpriseDB Corporation All rights reserved 223 Postgres Plus xDB Replication Server with Multi Master User s Guide Step 2 For MMR only Open the Scheduled Task Wizard dialog box in any of the following ways e Click the secondary mouse button on the Publication Database node and choose Configure Schedule e Click the primary mouse button on the Configure Schedule icon File Publication Subscrpton Help ta Replication Servers E Publication Server 192 168 10 102 9051 a SMR a MMR 192 168 10 102 a Postgres Plus Advanced Serve 5444 E emp_pub edb FE edb dept pubuser H E edb emp Yes 1 Not available E Postgres Plus Advanced Serve Figure 146 Opening the Scheduled
107. For Windows POSTGRES HOME enterprisedb edb replicator buildnn POSTGRES_ HOME is the home directory of the Windows postgres account enterprisedb account for Advanced Server installed in Oracle compatible configuration mode In the buildnn subdirectory nn is the xDB Replication Server Copyright 2012 EnterpriseDB Corporation All rights reserved 199 Postgres Plus xDB Replication Server with Multi Master User s Guide build number The specific location of POSTGRES_ HOME is dependent upon your version of Windows Snapshot emp_pub aDs J NAP gt NOI PLP rSnapshot Publication Name emp_pub Publisher IP 192 168 10 102 Publisher Por OK Figure 126 Successful on demand snapshot The publication has now been replicated from the master definition node to the selected master node A record of the snapshot is maintained in the replication history See Section 7 3 for information on how to view replication history 6 5 2 Performing Synchronization Replication When synchronization replication is performed in a multi master replication system a series of synchronization operations occur between every master node pair in the replication system For example if a replication system consists of master nodes A B and C synchronization is applied to the following node pairs whenever synchronization replication is initiated Copyright 2012 EnterpriseDB Corporation All rights reserved 200
108. HOME data The modifications needed to the pg_hba conf file for each of the three aforementioned cases are discussed in the following sections xDB Control Database On a database server on which an xDB Control database resides the following entries must be added to allow access to the xDB Control database host control dbname control dbuser pub _ipaddr 32 md5 host control dbname control dbuser sub_ipaddr 32 md5 Copyright 2012 EnterpriseDB Corporation All rights reserved 112 Postgres Plus xDB Replication Server with Multi Master User s Guide The values you substitute for control dbname and control dbuser are the entries for fields database and user in the xDB Replication Configuration file found on the hosts running the publication server and subscription server The following is an example of the content of an xDB Replication Configuration file user enterprisedb port 5444 password ygJ 9AxoJEX8 54elcVIJPTw type enterprisedb host localhost database xdb The values you substitute for pub _ipaddrand sub_ipaddr are the network IP addresses where the publication server and the subscription server are running Note The network IP addresses you substitute for pub_ipaddr and sub ipaddr must not be the loopback address 127 0 0 1 However the publication and subscription servers do require access to the xDB Control database using the loopback address as well This access is already granted in the default pg_hba conf fil
109. JDBC batches of SQL statements also referred to as transaction sets against the target tables The batches contain an INSERT statement for each shadow table row recording an insert operation an UPDATE statement for each shadow table row recording an update operation and a DELETE statement for each shadow table row recording a delete operation Each batch is executed in one transaction Shadow table rows that were applied to target tables can be viewed as shadow table history in the xDB Replication Console see Section 7 3 3 Note A single SQL statement executed against a source table may result in many rows recorded in a shadow table and therefore many SQL statements executed against the target table For example if a single UPDATE statement affects 10 rows in the source table 10 rows will be inserted into the shadow table one for each row in the source table that was updated When the publication server applies the changes to the target table 10 UPDATE statements will be executed Copyright 2012 EnterpriseDB Corporation All rights reserved 56 Postgres Plus xDB Replication Server with Multi Master User s Guide Note For greater efficiency when changes to the source tables consist of SQL statements that each affect a large number of rows the publication server may employ the use of prepared SQL statements See Section 5 8 2 for directions on how to control the usage of prepared SQL statement
110. MMR type node under the Publication Server node After the publication database definition is created a Publication Database node representing the master definition node appears in the replication tree of the xDB Replication Console A publication containing tables residing within this database can then be created under the Publication Database node You must enter database connection information such as the database server network address database identifier and database login user name and password when you create the publication database definition The connection information is used by the publication server to access the publication tables when it performs replication Step 1 Make sure the database server for the master definition node is running and accepting client connections Step 2 Select the MMR type node under the Publication Server node From the Publication menu choose Publication Database and then choose Add Database Alternatively click the secondary mouse button on the MMR type node and choose Add Database The Publication Service Add Database dialog box appears Step 3 Fill in the following fields Copyright 2012 EnterpriseDB Corporation All rights reserved 183 Postgres Plus xDB Replication Server with Multi Master User s Guide e Database Type Currently Postgres Plus Advanced Server is the only available option e Host IP address of the host on which the master definition node is running e Port Po
111. O INSERT INT O O TO O emp dept emp dept M emp emp dept emp emp dept i O O M dept O M O However in the following sequence it is better to use BUP mode Updates 1 thru 3 are batched in one prepared statement 4 thru 7 in another prepared statement 8 in its own prepared statement and then 9 thru 15 in one prepared statement i TNS ERT 2 INSERT 3 INSERT 4 UPDATE 5 UPDATE 6 UPDATE TEVRAT 8 INSERT 9 INSER 10 INSERT MTNS ERI TTN ER 13 INSERT ANSER Spee NS ENE The bup TE dep TE dep INTO emp INTO emp INTO emp dept E dept ite INTO emp l INTO dept INTO dept T INTO dept INTO dept INTO dept L INTO dept T INTO dept bupBatchThresholdCount option is used in combination with the BatchThresholdRepeatLimit option to control the frequency of mode switches based on the volatility of expected update types to the publication bupBatchThresholdCount m The default value for mis 5 bupBatchThresholdRepeatLimit n Copyright 2012 EnterpriseDB Corporation All rights reserved 172 Postgres Plus xDB Replication Server with Multi Master User s Guide The default value for n is 10 Each time the same prepared SQL statement is consecutively executed an internal batch counter is incremented If this batch count falls below bupBatchThresholdCount for the number of executions of a given prepared stateme
112. Oracle 192 168 2 6 1521 xe pubu i 19216826 i MMR Sort Oe i 4521 E subscription Server 192 168 2 7 9052 sD xe Figure 225 Remove Publication Database confirmation The Publication Database node no longer appears under the Publication Server node Figure 226 Replication tree after removing a publication database Copyright 2012 EnterpriseDB Corporation All rights reserved 301 Postgres Plus xDB Replication Server with Multi Master User s Guide 7 6 Replicating DDL Changes Once a replication system has been created and is in operation there may be occasions where it is necessary to make changes to the publication table definitions These data definition language DDL changes may include the following Adding new columns to a table Renaming existing columns Modifying a column data type Modifying a column constraint Removing columns The changes described are generally accomplished using the SQL ALTER TABLE statement which is issued in an SQL command line utility program such as PSQL The DDL change replication feature accepts a text file containing one or more ALTER TABLE statements The DDL change replication feature then performs the following actions e Applies the ALTER TABLE statements to the appropriate target table in the publication and subscription databases of a single master replication system or in all master nodes including the master definition
113. Plus Advanced Server 1 E edb dept S Postgres Plus Advanced Server 1 og Figure 123 Selecting a master node publication for an on demand snapshot Step 2 Open the Snapshot dialog box in any of the following ways e Click the secondary mouse button on the Publication node and choose Snapshot e Click the primary mouse button on the Snapshot icon Copyright 2012 EnterpriseDB Corporation All rights reserved 197 Postgres Plus xDB Replication Server with Multi Master User s Guide eg Postgres Plus Advanced Server 1 i ay emp pub FE edb emp cE Postgres Plus Advanced Server 1 ty i Snapshot Figure 124 Opening the Snapshot dialog box Step 3 Click the Snapshot button to start snapshot replication Copyright 2012 EnterpriseDB Corporation All rights reserved 198 Postgres Plus xDB Replication Server with Multi Master User s Guide f Snapshot emp_pub Snapshot Publication Name emp _pub Publisher IP 4 92 168 10 102 Publisher Port 9051 Snapshot Figure 125 Snapshot dialog box Step 4 Snapshot Taken Successfully appears if the snapshot was successful Click the OK button If the snapshot was not successful scroll through the messages in the Snapshot dialog box window The status messages of each snapshot are also saved in the Migration Toolkit log files named mtk_yyyymmddhhmi ss 1log in the following directories For Linux var log xdb rep buildnn
114. Postgres Plus xDB Replication Server with Multi Master User s Guide There are a number of characters that have special meaning that can be utilized in all fields unless noted Table 10 Cron Expression Special Characters Separates a list of values ON WED FRI Every Monday Wednesday and Friday Separates the low and high f d of a range of values ON FRI Every Monday through Friday y Allows all legal values for re P Ta field O 10 14 Every day of every month at 2 10 PM x i Specifies an increment i 0 0 10 Every 10 minutes starting on the hour starting with x for every day of every month e g 8 00 00 8 10 00 8 20 00 When used in the day of the month dd field means the 0 30 15 L 8 Every August 31 at 3 30 PM last day of the month When used by itself in the day of the week field dow means Saturday 30 0 12 AUG L The next Saturday in August at 30 seconds past 12 00 noon When used in the day of the week field dow following a day of the week means the last xxx day of the month Used in the day of the month field dd following a day of the month x to specify the weekday closest to x without going over into the next or previous month Used in the day of the week field dow to specify the nth xxx day of the month 30 0 12 AUG 6L The last Friday in August at 30 seconds past 12 00 noon 1w The weekday closest to the 1 of the month If the 1 is a Wedn
115. QL Server documentation for using SQL Server Management Studio Step 2 Required only for a SQL Server publication database Be sure SQL Server Agent is enabled and running SQL Server Agent is a Windows service that controls job scheduling and execution with SQL Server xDB Replication Server uses SQL Server Agent for certain operations such as for scheduled shadow table history cleanup see Section 7 4 1 Copyright 2012 EnterpriseDB Corporation All rights reserved 100 Postgres Plus xDB Replication Server with Multi Master User s Guide SQL Server Agent can be started by using SQL Server Configuration Manager Refer to the appropriate SQL Server documentation for using SQL Server Configuration Manager 5 1 2 Preparing the Publication Database This section discusses the preparation of a database that contains tables and views that will become members of publications The tables and views to be used for any given publication must all reside in the same database This database becomes the publication database of that publication A publication database user name must be created or already exist with the following characteristics e The publication database user can connect to the publication database e The publication database user has the privileges to create database objects to store metadata used for controlling and tracking the replication process e The publication database user can read the tables and views that are to beco
116. QueryTimeout option controls the timeout interval in milliseconds before an attempt by the publication server to apply a transaction set on a target database is aborted by the database server typically due to a lock acquired by another application on one or more of the target tables The targetDBQueryTimeout option changes the Postgres default lock timeout value of 15 minutes to 2 minutes Change the 2 minute default value to a higher value if you want to allow a longer wait time before the transaction is aborted However a higher value also delays processing of subsequent transaction sets on other target databases because if a transaction set is blocked the next transaction set cannot be loaded until 1 the lock is released and the blocked transaction set can then be applied to completion or 2 the targetDBQueryTimeout interval is exceeded If a timeout occurs the waiting transaction set is marked as aborted for the particular blocked target database The remaining pending transaction sets in this synchronization session are skipped for this target database but are applied to all other target databases once the timeout interval has been exceeded The aborted and skipped transaction sets are tried again when the next synchronization replication event occurs So for example in a 3 node cluster with ten pending transaction sets assume transaction set 1 is loaded and begins replicating to nodes 2 and node 3 Now another applic
117. RMM oeeo 94 4 1 5 Subscription Management ccssccesesrcee fee cesses ofl O d 95 42 Saving Server Login Information Ryy 4p See flee eeeeee EM eee 95 4 2 1 Server Login File ee eceeeceecees ME n Aee 96 4 2 2 Security Risks of Saved Server Login Information essesesesereeerereeresee 98 5 Single Master Replication Operation ssse e sssesseesseeeseesssseensesseesseeeseeeesseesseesseessee 99 5 1 Prerequisite Steps M OT CT 99 5 1 1 Enabling Access to the Database Servers sssessesssesssesessseessresseesseesseeesseee 99 5 1 2 Preparing the Publication Database uieessseeeeeseseeeeeseessrseresresserererresseesees 101 5 1 3 Preparing the Subscription Database 0 0 0 0 eeeceeeecceceeeeeceeececeteeeeeeeeesaes 107 5 1 4 Verifying Hogi cain lity ircesessccssscssssssccssscesssscssssccesssscecnacceencceenees 110 5 2 PMNS a Publication HMMM cceescccssrccsssrcesssrssessesessnccssssnceesscesensccesnaseesns 116 5 2 1 Registering a PublicatiGMVerver csscccsssccssssscssssccesssscsssscsesascecsscesenees 116 5 2 2 Adding a Publication Database ecesscecseeesceeseecesserceesescenseccetsersontees 120 5 2 3 Adding WLC AU QI 5535 se ens ctoemesi NM voscses gaucady de dpaeasetsaaeee tiueecaniseeetaeee eaters 123 5 2 4 Metadata Created for a Publication ee ee ceecseeeeereecneeceeeeeeeesneeeaeens 127 5 3 CPS ATED a SU OCU eisti dot Shed ere aaao tga etes ae
118. RT ON pubuser RRST edb emp TO new_user GRANT INSERT ON pubuser RRST edb jobhist TO new_user GO Using this approach however requires you to issue additional privileges for each application table that is added to a publication 5 1 2 3 Postgres Publication Database The following steps assume you wish to use a non superuser as the publication database user These steps can be omitted if you choose to use a superuser as the publication database user Alternatively most if not all of these steps can probably be omitted if you use the publication database owner as the publication database user You will need to check that the publication database user you choose has all of the privileges described in these steps Step 1 Create a database user name for the publication database user The publication database user name must have a password and it must have the ability to create a database session The publication database user becomes the owner of xDB Replication Server metadata database objects that will be created in the publication database to track control and record the replication process and history When creating the publication database definition the publication database user name is entered in the Publication Service Add Database dialog box see Section 5 2 2 CREATE ROLE pubuser WITH LOGIN PASSWORD password Step 2 Grant the privileges needed to create the xDB Replication Server metadata database objects
119. SELECT DISTINCT name FROM user source WHERE SOh gt SELECT Exagger name FROM user periggers no rows selected type PACKAGE For SQL Server only Most of the metadata database objects to manage the publication are created in the schema of your choosing when the publication database is prepared as described in Section 5 1 2 2 The following examples assume the metadata database objects are in schema pubuser The publication tables are dept and emp located in the edb schema The following query lists the metadata database objects located in the pubuser schema 1 gt USE edb 2 GO Changed database context to edb alls 2 gt SHUI snene m Yo a Onee WOojece Nenet Op yse Close Wolojecec Wyss 3 gt FROM sys objects o 4 gt sys schemas s 3 WHERE s name pubuser 6 gt AND o type IN U P 7 gt AND o schema_id s schema_id 8 gt ORDERTB ares RF I gt EO Object Name Object Type pubuser CleanupShadowTables SQL STORED PROCEDURE pubuser ConfigureCleanUpJob SQL STORED PROCEDURE pubuser ConfigureCreateTxSetJob SQL STORED PROCEDURE pubuser CreateMultiTxSet SQL STORED PROCEDURE pubuser CreateTableLogTrigger SQL STORED PROCEDURE pubuser CreateTxSe
120. Server 1 Y emp_pub Postgres Plus Advanced Server 1 Previous fire time Next fire time Figure 152 Selecting a master definition node whose schedule is to be updated Step 3 For SMR only Open the Scheduled Task Wizard dialog box in any of the following ways e From the subscription menu choose Schedule then Configure Schedule e Click the secondary mouse button on the Subscription node and choose Configure Schedule e Click the primary mouse button on the Configure Schedule icon Step 3 For MMR only Open the Scheduled Task Wizard dialog box in any of the following ways e Click the secondary mouse button on the Publication Database node and choose Configure Schedule e Click the primary mouse button on the Configure Schedule icon Copyright 2012 EnterpriseDB Corporation All rights reserved 229 Postgres Plus xDB Replication Server with Multi Master User s Guide tq Replication Servers Publication Server 192 168 2 7 9051 E Subscription Server 192 168 2 7 9052 GR Postgres Plus Advanced Server 192 tg H S sales_dept Figure 153 Opening the Scheduled Task Wizard dialog box from the tool bar Step 4 The Configure Scheduler confirmation box appears Click the Yes button H Publication Server 192 168 2 7 9051 B Subscription Server 192 168 2 7 9052 MON WED FRI SUN Figure 154 Configure Scheduler confirmation Copyright 2012 EnterpriseDB C
121. Step 3 See Section 5 2 1 for directions on restarting a publication server Step 5 In the subscription database create the schema the subscription table definitions and load the subscription tables from your offline data source The subscription database user name used in Section 5 3 2 must have full privileges over the database objects created in this step Also review the beginning of Section 5 3 2 regarding the rules as to how xDB Replication Server creates the subscription definitions from the publication for each database type as you must follow these same conventions when you create the target definitions manually Step 6 Add the subscription as described in Section 5 3 3 Step 7 Perform an on demand synchronization replication See Section 5 4 2 for directions on performing an on demand synchronization replication Step 8 If you are not planning to load any other subscriptions using an offline snapshot at this time change the of flineSnapshot option back to false and the batchInitialSync option to true in the publication server configuration file Step 9 Restart the publication server if you modified the publication server configuration file in Step 8 7 7 4 Multi Master Replication Offline Snapshot An offline snapshot can be used to initially load the master nodes of a multi master replication system It is possible to load some of the master nodes using the xDB Replication Server snapshot replication functionality when de
122. Synchronize w Subscription Server 192 168 10 102 9052 36 Synchronize Success Synchronize 2011 05 25 15 59 31 Success Snapshot Information Message Currently there is no data available to display for this transaction because all the synchronization history has been cleaned up Figure 177 View Data link after shadow table history cleanup Copyright 2012 EnterpriseDB Corporation All rights reserved 251 Postgres Plus xDB Replication Server with Multi Master User s Guide 7 4 3 Cleaning Up Replication History Cleaning up replication history deletes rows from the following metadata tables in the _edb replicator pub schema of the xDB Control database e erep pub _replog e erep pub _ table replog The following are the steps to run replication history cleanup for a chosen publication Step 1 Make sure the publication server whose node is the parent of the publication whose replication history you wish to cleanup is running and has been registered in the XDB Replication Console you are using See Section 5 2 1 for directions on starting and registering a publication server Step 2 Select the Publication node of the publication for which you want to clean up replication history File Publication Subscription Help 9 UMA OL o General Realtime Monitor Replication H G eS Publication Server 192 168 2 7 9051 DA MMR 2S SMR Publication schema i w Oracle 192 168 2 6 1521 xe pubu Table count tg
123. T TABLE EDB EMP TABLE EDB JOBHIST TABLE VIEW EDB SALESEMP 8 3 11 Creating a Publication createpub The createpub command creates a new publication Copyright 2012 EnterpriseDB Corporation All rights reserved 329 Postgres Plus xDB Replication Server with Multi Master User s Guide Synopsis createpub pubname repsvrfile pubsvrfile pubdbid dbid reptype s t tables schema_tl table_1 schema t2 table 2 views schema vl view 1 schema v2 view 2 tablesfilterclause ordinal t1 filter tl bo Ordinal C2 filter te ass viewsfilterclause ordinal vi filter_vi ordinal v2 filter v2 rel conflictresolution ordinal ti E L N M ordinal t2 E L N Me standbyconflictresolution ordinal t1 4 E LIN M ordinal t2 E L N M repgrouptype m s The createpub command adds a new publication subordinate to the publication database definition with the publication database ID given by parameter pubdbid If the publication is designated as snapshot only by setting parameter rept ype to s then any views listed after the views parameter are ignored See Section 5 2 3 for additional information on creating a publication for a single master replication system See Section 6 2 3 for a multi master replication system Note The schema names table n
124. T before data load Disabling indexes on edb dept before data load loading laine SDE Ei er DEPT Migrated 4 rows DEPT Table Data Load Summary Total Time s 0 182 Total Rows 4 Disabling FK constraints amp triggers on edb emp before truncate Truncating table EMP before data load Disabling indexes on edb emp before data load Loading Table EMP EMP Migrated 14 rows EMP Table Data Load Summary Total Time s 0 178 Total Rows 14 Copyright 2012 EnterpriseDB Corporation All rights reserved 357 Postgres Plus xDB Replication Server with Multi Master User s Guide Enabling FK constraints amp triggers on edb dept Enabling indexes on edb dept after data load Enabling FK constraints amp triggers on edb emp Enabling indexes on edb emp after data load Performing ANALYZE on EnterpriseDB database Data Load Summary Total Time sec 1 866 Total Rows 18 Total Size MB 0 0 Schema EDB imported successfully Migration process completed successfully Migration logs have been saved to var log xdb rep build571 KKEKKKKKKKKKKKKKK KK KK Migration Summary KEKKKKKKKKKKKKKKKKKK WaAlgilkess 2 othe iF 2 Constraints 4 out of 4 Total objects 6 Successful count 6 Failure count 0 KKEKKKKKKKKKKKEKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKK Snapshot taken successfully 8 3 34 Take a Multi Master
125. TES Osc0 0 WinEeress COE molil teste lina 2 The same circumstance may also produce the following error in the Migration Toolkit log file Loading Table Data in 8 MB batches Disabling INK constraints wisileeeics om Sclonmullll elgg betore CTUnCaACS oo Disabling indexes on edb null _clob before data load Loading Large Objects into table NULL CLOB NULL _CLOB Migrated 1 rows com edb util PSOQLException Zero bytes may not occur in string parameters Skipping Batch Copyright 2012 EnterpriseDB Corporation All rights reserved 397 Postgres Plus xDB Replication Server with Multi Master User s Guide If any of these errors occur you can set an option that will convert each null character encountered in character columns of the source tables to a space character or to any other character of your choice before loading the target tables Note This option does not alter null characters encountered in columns with binary data types such as Oracle RAW and BLOB data types Set the following option replaceNullChar true This option results in the substitution of a space character for each null character encountered in the source character data If you want to use a character other than a space character to replace each null character use the following option in addition to replaceNullChar true nullReplacementChar char char 1s a single character you want to substitute
126. The first type of update is discussed in the following section The second type of update is discussed in Section 7 5 1 2 7 5 1 1 Publication Server Login File When you register a publication server in the xDB Replication Console you may choose to save the publication server s network location user name and encrypted password in a server login file on the computer on which you are running the xDB Replication Console See Section 4 2 for information on saving the login information The steps described in this section show you how to update the publication server s login information in the server login file Copyright 2012 EnterpriseDB Corporation All rights reserved 256 Postgres Plus xDB Replication Server with Multi Master User s Guide It is assumed that the xDB Replication Console is open on your computer and the publication server whose login information you wish to alter in the server login file appears as a Publication Server node in the xDB Replication Console s replication tree File Publication Subscription Help SSUy CGH General Realtime Monitor Replication History Ea MMR Property SMR Service status Stopped i Subscription Server 192 168 2 7 9052 Publication database count Not Available Figure 183 Publication Server node You can perform the following actions on the server login file e Change the publication server s login information host IP address port number
127. US mode to BUP mode if dynamic switching is permitted that is switchBatchUpdateMode true busBatchThresholdCount n The default value for n is 50 The number of consecutive changes using the same table and SQL statement type must exceed the specified value n before a prepared statement is used Setting this threshold to a low value will encourage higher use of prepared statements while setting it to a high value will limit the use of prepared statements If changes to the publication were made using many SQL statements where each statement affected more than one row then it may be beneficial to lower Copyright 2012 EnterpriseDB Corporation All rights reserved 171 Postgres Plus xDB Replication Server with Multi Master User s Guide busBatchThresholdCount to encourage the use of prepared statements on the multiple shadow table rows resulting from each individual change on the publication bupBatchThresholdCount and bupBatchThresholdRepeatLimit If BUP mode is employed but the number of updates using the same prepared statement is low causing frequent switches to a new prepared statement it may be more beneficial to use individual SQL statements BUS mode For example the following sequence of updates would be better processed in BUS mode INSERT INT INSERT INT INSERT INT INSERT INT DELETE FRO UPDATE emp UPDATE dep INSERT IN INSERT INT DELETE FRO INSERT INT DELETE FR
128. a statement failure in certain cases This section discusses how to deal with the preceding two points for both a single master and a multi master replication system Copyright 2012 EnterpriseDB Corporation All rights reserved 307 Postgres Plus xDB Replication Server with Multi Master User s Guide First non batch mode synchronization and why it must be used in certain cases is explained in more detail in the following section 7 7 1 Non Batch Mode Synchronization Synchronization replications are done in batches of updates each batch committed in a separate transaction Therefore if any single update in a batch fails all the updates in the batch are rolled back This process has the following implications Prior to and during the time when the offline snapshot is in progress there may be updates to the source tables which are recorded in the source tables shadow tables After the offline snapshot completes there may be additional updates to the source tables that are also recorded in the shadow tables Since xDB Replication Server has no knowledge of the external data source used to load the target tables it is unknown to xDB Replication Server whether or not any of the updates made to the source tables during or after the offline snapshot have already been included in the data used to load the target tables As a result the shadow tables may include a mixture of duplicate updates that have already been applied to the t
129. abase definition e In the publication database a database user must exist that is to be the creator and owner of the xDB Replication Server metadata database objects This database user must be mapped to the SQL Server login used by the publication server e A schema must exist to contain the xDB Replication Server metadata database objects The database user described in the preceding bullet point must either own this schema or have certain privileges on this schema so that the database user can create and update the metadata database objects in this schema This schema must also be defined as the default schema of that database user e The SQL Server database users that update the data in the application tables that are to be replicated must have certain privileges on the xDB Replication Server metadata database objects When an update on a replicated table occurs a trigger fires that updates certain metadata database objects using the privileges associated with the application user performing the update These privileges are granted to existing SQL Server database users however if new SQL Server database users are added who require update access to the application tables then privileges must be granted to these users on the xDB Replication Server metadata database objects e A database user must exist in the msdb database that is mapped to the SQL Server login used by the publication server This database user must have certain privileges to
130. able in the control schema This option should be disabled in a production environment to avoid performance overhead Copyright 2012 EnterpriseDB Corporation All rights reserved 176 Postgres Plus xDB Replication Server with Multi Master User s Guide enablePerformanceStats true false The default value is false Copyright 2012 EnterpriseDB Corporation All rights reserved 177 Postgres Plus xDB Replication Server with Multi Master User s Guide 6 Multi Master Replication Operation This chapter describes how to configure and run xDB Replication Server for multi master replication systems For configuration and management of your replication system the xDB Replication Console graphical user interface is used to illustrate the steps and examples in this chapter The same steps can be performed from the operating system command line using the xDB Replication Server Command Line Interface CLI The commands of the xDB Replication Server CLI utility are described in Chapter 8 6 1 Prerequisite Steps Certain steps must be taken to prepare the host environments as well as the database servers used as master nodes before beginning the process of building a multi master replication system This section describes these steps 6 1 1 Preparing the Master Definition Node This section discusses the preparation of a database to be used as the master definition node When creating the publication database definition for the master
131. ables dept and emp For Oracle only The metadata database objects to manage the publication are created in the publication database user s schema as shown in the following output SQL gt CONNECT pubuser password Connected SQL gt SET PAGESIZE 9999 SQL gt SELECT table name FROM user tables TABLE NA RREP_ TABLES RREP PUBLICATION TABLES RREP_TXSET RREP MMR TXSET RREP_ PUBLICATION SUBSCRIPTIONS RREP_TXSET_ LOG RREP_LOCK RREP MMR PUB_GROUP RREP_ PROPERTIES RREP_TXSET HEALTH RRST_EDB DEPT RRST_EDB EMP SQL gt SELECT DISTINCT name FROM user source WHERE type PACKAG ES Copyright 2012 EnterpriseDB Corporation All rights reserved 386 Postgres Plus xDB Replication Server with Multi Master User s Guide RREP_ PKG SQL gt SELECT trigger name FROM user triggers TRIGGER NAME REE ISDE RET RRPU_EDB DEPT RRPD EDB DEPT RRPI_EDB_EMP RRPU_EDB_ EMP RRPD EDB_ EMP 6 rows selected Note the following in the preceding output e The tables named according to the convention RRST_schema_table from the SELECT statement on user tables are found only for synchronization publications In this example these ta
132. accepted and replicated to all other master nodes All other conflicting changes are discarded e Node Priority The conflicting change occurring on the master node with the highest priority level is accepted and replicated to all other master nodes All other conflicting changes are discarded e Manual The conflict remains unresolved Conflicting changes remain applied in each master node where they originated but are not replicated to other master nodes The proper adjustments must be manually applied in each master node See Section 6 6 3 for more information on conflict resolution strategies Step 4 Click the Create button If Publication Created Successfully appears click the OK button otherwise investigate the error and make the necessary corrections Create Publication Conflict Resolution Options Conflict Resolution Strategy Standby Conflict Resolution Strategy Earliest Timestamp Manual artesi Tmesian Create Publication 9 Publication created successfully Ca Figure 117 Publication created successfully Upon successful publication creation a Publication node is added to the replication tree Copyright 2012 EnterpriseDB Corporation All rights reserved 189 Postgres Plus xDB Replication Server with Multi Master User s Guide File Publication Subscription Help USUy OGRE Je cee Savers N General Realtime Monitor Replication History Conflict History
133. aconflict is detected the conflict information such as the transaction ID conflict type and conflict detection timestamp are logged in the conflict table on the target master node e Fora conflicting transaction the replication server checks if any conflict resolution strategy has been selected for the specific table If a strategy is found it is applied accordingly and the conflict status is marked as resolved If a strategy cannot be applied the conflict status is marked as unresolved also called pending e Ifno conflict is detected the transactional change is replicated to the target master node and the transaction status for that target node is marked as completed in the source master node control schema A transaction status mapping for each target Copyright 2012 EnterpriseDB Corporation All rights reserved 206 Postgres Plus xDB Replication Server with Multi Master User s Guide master node is maintained on all master nodes For example node A contains two mappings of status one for node B and another for node C e All of these prior steps are repeated to process and replicate all pending transaction sets available on master node A to master node B e Next the publication server proceeds to replicate master node A pending transactional changes to the next target master node C e Once the master node A changes are replicated to nodes B and C the publication server replicates the pending changes available on master node B
134. ae a ges aiis 130 5 3 1 Registering a Subscription Server icsics ssassisescatsauavcasasassndcnasaceddandavedeareereee 131 5 3 2 Adding a Subscription Database jia c cas siapieseteeetivead peasisatrnpaenden oteaates aes 133 5 3 3 gt Adding a S UBS CM PUG Hschcstacctatsasececnaiee ecaecasceteateaseaceaauaees sieaeeaniaseaeeesionenaea des 137 5 3 4 Metadata Created for a Subscription ss ssesssesssesesssesssressersserssseessseesseese 140 5 4 On Demand Replic tigii iesise esteisiin Sees agtet ais 141 5 4 1 Performing Snapshot Replication ssssssssessesssessseressseesseessrssersseeessseesseese 142 5 4 2 Performing Synchronization Replication seseseessseeesseesserssessseresssessee 145 5 5 Managing a Subscription ssssssessessseessesessseesseessressessseeesseeesstesseesseesseeessseesseese 148 Copyright 2012 EnterpriseDB Corporation All rights reserved 4 Postgres Plus xDB Replication Server with Multi Master User s Guide 5 5 1 Updating a Subscription Server i s i c ssiccssesscesssesdeatacsesedcocdecessonceedeecessaae 148 5 5 2 Updating a Subscription Database vijeiirvcyicesesvecqensacaadovadaqeysaaciaserhedaseeseuedte 151 5 5 3 Updating a Subscription 5 ssitsivccesnssesacdadessieese seatssteagacceseeenctaannextae todenumeauavace 155 554 Removing a SUbsenipuon chen ee Ta a E cantina 157 5 5 5 Removing a Subscription Database sssessesssesseeessseessesseesseesseessseesseese 160 5 6 Performing Controlled Switc
135. ake the necessary corrections Copyright 2012 EnterpriseDB Corporation All rights reserved 271 Postgres Plus xDB Replication Server with Multi Master User s Guide Add Tables Publication sales_dept Add Tables Filter Clause Specify a filter criteria to exclude table rows from replication The filter criteria is a SQL WHERE CLAUSE without WHERE keyword For example state CA Table Type Filter EDB JOBHIST deptno 30 Add Tables Publication sales_dept Q Publication updated successfully Add Tables Figure 197 Successfully added tables to publication Step 6 For MMR only Click the Add Tables button The Data Sync Check dialog box appears warning you that synchronization replication is performed before the table is added If you wish to perform synchronization at some later point in time then add the table click the No button If you wish to proceed click the Yes button If Publication Updated Successfully appears click the OK button otherwise investigate the error and make the necessary corrections Copyright 2012 EnterpriseDB Corporation All rights reserved 272 Postgres Plus xDB Replication Server with Multi Master User s Guide An implicit Synchronize will be performed to replicate pending transactional changes for the existing tables that can prolong the operation depending on the backlog size It s recommended to perform the Synchro
136. ames and view names that you supply as values for the tables and views parameters are case sensitive Unless quoted identifiers were used to build the database objects Oracle names must be entered using uppercase letters for example EDB DEPT and Advanced Server names must be entered in lowercase letters for example edb dept See Section 9 3 5 for additional information on quoted identifiers and case translation Parameters pubname The publication name to be given to the new publication pubsvrfile The file containing the publication server login information dbid The publication database ID of the publication database definition subordinate to which the new publication is to be added Copyright 2012 EnterpriseDB Corporation All rights reserved 330 Postgres Plus xDB Replication Server with Multi Master User s Guide reptype Specify s if the publication is to be a snapshot only publication Specify t if the publication is to allow synchronization replications schema tn The name of the schema containing the nth table of the tables parameter list This value is case sensitive table_n The table name of the nth table in the tables parameter list This value is case sensitive schema_vn For SMR only The name of the schema containing the nth view of the views parameter list This value is case sensitive view n For SMR only View name of the nth view in the views parameter list This value is
137. ameter in the postgresql conf file of the target Postgres database server must be off thereby disabling archiving of WAL data in order to use the useFastCopy option useFastCopy true false The default value is false cpBatchSize Use the cpBatchSize option to set the batch size in Megabytes that is used in the JDBC copy operation during a snapshot Increase the value of this option for large publication tables This option is influential when Postgres is the subscription database since the JDBC COPY operation is used to load Postgres subscription tables This option has no effect when Oracle or SQL Server is the subscription database To tune loading of Oracle or SQL Server tables alter the batchSize option cpBatchSize n The default value for n is 8 batchSize The batchSize option controls the number of INSERT statements in a JDBC batch This option is particularly significant when Oracle or SQL Server is the subscription database since tables of these database types are loaded using JDBC batches of INSERT statements For a Postgres subscription database tables are loaded using JDBC Copy however if the COPY operation fails for some reason then table loading is retried using JDBC batches of NSERT statements as in the case of Oracle and SQL Server batchSize n The default value for n is 100 Copyright 2012 EnterpriseDB Corporation All rights reserved 168 Postgre
138. arget tables as well as new updates that have not been applied to the target tables If you then perform synchronization replication the publication server attempts to apply all updates recorded in the shadow tables in batches If one of the updates had been an insertion of a new row and this new row is already in the target table loaded from the offline snapshot a duplicate key error results when the publication server attempts to apply the batch containing the INSERT statement for this row The duplicate key error forces the rollback of the entire batch This causes the exclusion of updates in the batch that may not yet have been carried over to the target tables The source tables and target tables are now inconsistent since there were updates to the source tables that have not been applied to the target tables Note The effects of applying UPDATE and DELETE statements in the batch to a target table that already has been changed by these updates does not cause the same problem as repeated application of INSERT statements The UPDATE statement would just change the row to the same values a second time When a DELETE statement affects no rows this is not considered an error by the database server and therefore no rollback of the batch occurs The solution to the potential rollback of a batch is to apply the shadow table updates in non batch mode That is each SQL statement is indiv
139. as well e Select All Check this box if you want to include all tables and views in the Available Tables list in the publication Create Publication s Create Publication Filter Clause Publication Name sales_dept Snapshot only replication Publish Available Tables V EDB DEPT EDB EMP EDB JOBHIST Select All Figure 70 Create Publication dialog box If you wish to omit certain rows of the publication tables or views from being replicated follow the directions in the next step to create a filter otherwise go on to Step 4 Step 3 Optional If you want to filter the rows of the publication tables or views click the Filter Clause tab Enter an appropriate SQL WHERE clause in the text box next to a table or view to select the rows you want to replicate Copyright 2012 EnterpriseDB Corporation All rights reserved 124 Postgres Plus xDB Replication Server with Multi Master User s Guide In the following example only rows where the deptno column contains 30 are included in replications All other rows are excluded from replication Create Publication Create Publication Filter Clause Specify a filter criteria to exclude table rows from replication The filter criteria is a SQL WHERE CLAUSE without WHERE keyword For example state CA Type Fitter deptno 30 deptno 30 Figure 71 Adding a filter cla
140. ase subdb Figure 78 Subscription Service Add Database dialog box Step 4 Click the Test button If Test Result Success appears click the OK button then click the Save button Copyright 2012 EnterpriseDB Corporation All rights reserved 135 Postgres Plus xDB Replication Server with Multi Master User s Guide Figure 79 Successful subscription database test If an error message appears investigate the cause of the error correct the problem and repeat steps 1 through 4 When the subscription database definition is successfully saved a Subscription Database node is added to the replication tree under the Subscription Server node tS in hg 2 tq Replication Servers k General amp Publication Server 192 168 2 7 9051 BS SMR Property amp g Oracle 192 168 2 6 1521 xe pubuser Host 192 168 2 7 ay sales_dept Port 5444 H E EDB DEPT Database subdb EE EDB EMP User subuser MMR Zi Subscription Server 192 168 2 7 9052 Postgres Plus Advanced Server 192 168 2 7 5444 subdb subuser Figure 80 Replication tree after adding a subscription database Copyright 2012 EnterpriseDB Corporation All rights reserved 136 Postgres Plus xDB Replication Server with Multi Master User s Guide 5 3 3 Adding a Subscription Subordinate to a subscription database definition you create subscriptions A subscription assigns the publication that is to be replicated to th
141. aster User s Guide Snapshot sales_dept_sub mtm Snapshot Subscription Name sales_dept_sub Publisher IP 192 168 2 7 Publisher Port 9051 Snapshot Figure 88 Snapshot dialog box Step 4 Snapshot Taken Successfully appears if the snapshot was successful Click the OK button If the snapshot was not successful scroll through the messages in the Snapshot dialog box window The status messages of each snapshot are also saved in the Migration Toolkit log files named mtk_yyyymmddhhmiss 1og in the following directories For Linux var log xdb rep buildnn For Windows POSTGRES HOME enterprisedb edb replicator buildnn POSTGRES_ HOME is the home directory of the Windows postgres account enterprisedb account for Advanced Server installed in Oracle compatible configuration mode In the buildnn subdirectory nn is the xDB Replication Server Copyright 2012 EnterpriseDB Corporation All rights reserved 144 Postgres Plus xDB Replication Server with Multi Master User s Guide build number The specific location of POSTGRES_ HOME is dependent upon your version of Windows Snapshot sales_dept_sub r Snapshot L Publisher IP 192 168 2 7 Subscription Name sales_dept_sub Publisher Pon OK Snapshot Figure 89 Successful on demand snapshot The publication has now been replicated to the subscription database A record of the snapshot is maintained in t
142. atabase system e Remove the publication See Section 7 5 5 for directions to remove a publication e Re add the publication See Section 5 2 3 for directions to add a publication e Re add the subscription See Section 5 3 3 for directions to add a subscription In a multi master replication system if changes were made to the definitions of one or more publication tables on one or more master nodes the resolution to the problem involves e Making sure the table definitions are updated on all master nodes so that they are identical or updating the table definition on the master definition node so it can be replicated to the other master nodes e Recreating the publication database definitions of the master nodes The general steps are the following e Remove the publication database definitions of all master nodes except for the master definition node See Section 7 5 6 for directions to remove a publication database definition e Remove the publication See Section 7 5 5 for directions to remove a publication e Remove the publication database definition of the master definition node See Section 7 5 6 for directions to remove a publication database definition Copyright 2012 EnterpriseDB Corporation All rights reserved 289 Postgres Plus xDB Replication Server with Multi Master User s Guide e At this point all of the triggers shadow tables and metadata have been removed from the master nodes e With respect
143. atabase user name for Oracle or edb replicator pub for Postgres is missing or there are no database objects under the metadata schema then you must complete the process of removing all remaining metadata database objects If the metadata database objects look intact go on to Step 5 For Oracle only If the publication user name still exists then log onto SQL Plus or any other Oracle database administration utility and drop all objects owned by the publication Copyright 2012 EnterpriseDB Corporation All rights reserved 390 Postgres Plus xDB Replication Server with Multi Master User s Guide user Alternatively you can drop the publication database user along with its database objects using the cascade option but the publication database user must be recreated and privileges reassigned if you intend to rebuild your replication systems See Section 5 1 2 for directions on creating the publication database user The following example illustrates use of the cascade option SQL gt CONNECT system password Connected SQL gt DROP USER pubuser CASCADE User dropped For SQL Server only If any of the metadata database objects listed in Step 3 still exist then log onto the SQL Server command line program sqicmd or SQL Server Management Studio and drop these objects The following example assumes the metadata database objects were created under schema pubuser The publication tables are dept and emp located in schema edb
144. ate the error and make the necessary corrections Copyright 2012 EnterpriseDB Corporation All rights reserved 138 Postgres Plus xDB Replication Server with Multi Master User s Guide Figure 82 Subscription created successfully Upon successful subscription creation a Subscription node is added to the replication tree g Replication Servers E Publication Server 192 168 2 7 9051 Ba sur amp Oracle 192 168 2 6 1521 xe pubuser amp ey sales_dept H E EDB DEPT amp EDB EMP coo MMR S Subscription Server 192 168 2 7 9052 R Postgres Plus Advanced Server 192 168 2 7 5444 subdb subuser 5 amp sales_dept EE EDB DEPT H E EDB EMP Publication server 192 168 2 7 Publication server port 9051 Scheduled job status Not available Figure 83 Replication tree after adding a subscription Copyright 2012 EnterpriseDB Corporation All rights reserved 139 Postgres Plus xDB Replication Server with Multi Master User s Guide The tables and views from the publication are created in the subscription database but without any rows Rows are populated into the subscription tables when the first snapshot replication occurs D Po ostgres Enterpris File Edit Plugins View Management Tools Help 2350 3280 708 Object browser Xo SPENNE o E Properties X Statistics Server Groups B Servers 1 f Table Owner B Postgres Plus Advanced Server 9 1 local
145. ation acquires a lock on one or more tables in node 2 putting the updates to these tables in a wait state Replication of transaction set 1 can run to completion on node 3 but if the wait time exceeds the targetDBQueryTimeout interval the database server cancels transaction set 1 on node 2 Replication of this transaction set to node 2 is marked as aborted in the xDB Replication Server metadata Transaction set 2 can now be loaded and run against node 3 Execution of transaction set 2 against node 2 is skipped since transaction sets must be applied in order and transaction set 1 was not successfully applied to node 2 Transaction sets 3 thru 10 are loaded and applied in order against node 3 but skipped for node 2 In the next synchronization replication transaction set 2 is tried again on node 2 If the lock has been released and the transaction set is applied successfully the remaining transaction sets 3 thru 10 are applied to node 2 Finally synchronization replication continues with any new transaction sets targetDBQueryTimeout n The default value is 120000 5 8 2 3 Other Synchronization Configuration Options The following are other configuration options affecting synchronization replication Copyright 2012 EnterpriseDB Corporation All rights reserved 175 Postgres Plus xDB Replication Server with Multi Master User s Guide syncBatchSize The syncBatchSize option controls the number of statements in a synchron
146. ation Server with Multi Master User s Guide Step 3 Click the Synchronize button to start synchronization replication Figure 92 Synchronize dialog box Step 4 Subscription Synchronized Successfully appears if the synchronization was successful Click the OK button If the synchronization was not successful scroll through the messages in the Synchronize dialog box window Figure 93 Successful on demand synchronization Copyright 2012 EnterpriseDB Corporation All rights reserved 147 Postgres Plus xDB Replication Server with Multi Master User s Guide The operations that were applied to the subscription tables can be seen in the replication history See Section 7 3 for information on how to view replication history 5 5 Managing a Subscription Note This section discusses various aspects of managing a subscription of a replication system For a similar discussion on managing a publication of a replication system see Section 7 5 After a subscription has been created certain aspects of the underlying replication system environment might be subsequently altered for any number of reasons Attributes that might change include the network location of the subscription database server the network location of the host running the subscription server database or operating system user names and passwords and so forth The aforementioned information is saved in the replication system metadata when a subscription is created Cha
147. ation tables Removing the Publication Database node representing the master definition node entails the following steps e All Publication Database nodes representing master nodes other than the master definition node must be removed Repeat the process described in this section for each such master node e The publication under the Publication Database node representing the master definition node must be removed See Section 7 5 5 for directions on removing a publication e Remove the Publication Database node representing the master definition node using the process described in this section Removing a Publication Database node does not delete the physical database from the database server It removes the identity and association of the database to xDB Replication Server so no further replications can originate from tables in the database unless there are other publication database definitions in xDB Replication Server with the same host and database identifier The physical database can only be removed using the database management system s database removal procedures The publication database user name is also left intact All xDB Replication Server metadata database objects created for that publication database definition are deleted For Oracle and SQL Server All metadata database objects under the publication database user s schema are deleted Copyright 2012 EnterpriseDB Corporation All rights reserved 299 Postgres
148. ations 0 o 17401 FTS Dictionaries 0 FTS Parsers 0 Owner FTS Templates 0 E Tablespace pg_default gt Functions 0 PSlac f Packages 0 Of type Procedures 0 ES Primary key fi amp gt Sequences 0 F Rows estimated 3 ESFil factor m7 SQL pane E Table edb variant_tbl 4 4 Constraints 1 i Indexes 0 DROP TABLE edb variant_tbl lll Rules 0 P wll Triggers 0 a TABLE edb variant_tbl D Trigger Functions 0 TA Views 0 fl integer NOT NULL BS 0 2 sql_variant ig Synonyms 0 CONSTRAINT pk_variant _32139e580d64f3ed PRIMARY KEY f1 public ag Collations 0 A WITH y Domains 1 OIDS FALSE gt f sql_variant j m j r Figure 235 Subscription table with sql_variant column 9 3 7 Restricted Mode Operation Restricted mode refers to limitations on certain xDB Replication Server operations after your trial period expires Restricted mode can be lifted by registering your xDB Replication Server product as described in Section 3 3 Restricted mode currently affects multi master replication systems Creation and usage of single master replication systems are not affected The following multi master replication operations are restricted e New master definition nodes or master nodes cannot be created see sections 6 2 2 and 6 3 However existing master nodes and master definition nodes remain operational e New publications cannot be c
149. b command adds a publication database definition Synopsis addpubdb Copyright 2012 EnterpriseDB Corporation All rights reserved 321 Postgres Plus xDB Replication Server with Multi Master User s Guide repsvrfile pubsvrfile dbtype oracle enterprisedb postgresql sqlserver dbhost host dbport port dbuser user dbpassword encrypted pwd dbpassfile pwdfile oraconnectiontype sid servicename database dbname repgrouptype m s replicatepubschema true false initialsnapshot nodepriority priority level oes lees lees ee The addpubdb command creates a new publication database definition The addpubdb command displays a unique publication database ID that is assigned to the newly created publication database definition The publication database ID is used to identify the publication database definition on which to operate when running other xDB Replication Server CLI commands See Section 5 2 2 for details on the database connection information that must be supplied when adding a publication database definition for a single master replication system See sections 6 2 2 and 6 3 for a multi master replication system Parameters pubsvrfile The file containing the publication server login information dbtype Specify oracle if the database is an Oracle database Specify enterprisedb if the database is an Advanced Server database in Oracle compatible configuration mode Specify postgresq
150. base That is the tables that were formerly publications become the subscription tables The former subscription tables now become the publications Controlled switchover is useful for situations where the publication database must be taken offline such as for periodic maintenance After the switchover applications connect to the former subscription database to perform their queries and updates while the former publication database is kept synchronized by replication Updates for replication are accumulated in shadow tables that are created on the former subscription tables during the controlled switchover procedure When the former publication database is online it is synchronized as the target of replication When you determine that you want to reverse the roles again so that the original publication database directly receives queries and updates from applications and the original subscription database receives updates by replication you perform the controlled switchover procedure once again switching the roles back 5 6 1 Controlled Switchover Overview When you perform controlled switchover you are modifying the replication system so that the database identified and referenced in the replication system metadata as the publication database is the physical database that was originally defined as the subscription database Similarly the database identified and referenced in the replication system metadata as the subscription database is
151. ble ACL FTS Configurations 0 e aA ee FTS Dictionaries 0 e ncuon E FTS Parsers 0 E System schema No ik FTS Templates 0 E Comment gt Functions 0 A Packages 1 Procedures 0 Gi Sequences 3 _ if Tables 12 H E rrep_lock E rrep_mmr_pub_group E rrep_mmr_txset E rrep_properties E rrep_publication_subscriptions _ E rrep_publication_tables E rrep_tables E rrep_txset E rrep_txset_health E rrep_txset_log E rrst_edb_dept E rrst_edb_emp 1 B RKI Trigger Functions 0 X a m J m n p P A A AAAAAAAA Figure 74 Postgres metadata database objects in the publication database Do not delete any of these database objects as the replication system metadata will become corrupted When you remove publications and publication database definitions using the xDB Replication Console or xDB Replication Server CLI these database objects are deleted during this process 5 3 Creating a Subscription Creating your first subscription requires the following steps e Registering the subscription server e Adding the subscription database e Creating a subscription by choosing the publication to which to subscribe Copyright 2012 EnterpriseDB Corporation All rights reserved 130 Postgres Plus xDB Replication Server with Multi Master User s Guide As many subscriptions can be created in the subscription database as there are available publica
152. bles e The database identifier if the new database identifier references a different physical database than where the subscription tables already reside Attributes you may change include the following e The login user name s password to match a changed database user password e The database server network location if the corresponding location change was made to the database server that accesses the subscription database e The database identifier such as the Oracle service name SQL Server database name or Postgres database name if the corresponding name change was made on the database server e All attributes may be changed if there are no existing subscriptions Step 1 Make sure the database server that you ultimately wish to save as the subscription database definition is running and accepting client connections Step 2 Make sure the subscription server whose node is the parent of the subscription database definition you wish to change is running and has been registered in the xDB Replication Console you are using See Section 5 3 1 for directions on starting and registering a subscription server Step 3 Select the Subscription Database node corresponding to the subscription database definition that you wish to update File Publication Subscription Help S UBWY GGI g Replication Servers N General E3 amp Publication Server 192 168 2 7 9051 Subscription Server 192 168 2 7 9052 Proper
153. bles are RRST_EDB DEPT and RRST _EDB EMP e The triggers named according to the convention RRPD schema table RRPI_schema_table and RRPU_schema_table from the SELECT statement on user triggers are found only for synchronization publications In this example these triggers are RRPU_EDB DEPT RRPI EDB DEPT RRPD EDB DEPT RRPI EDB EMP RRPU_EDB EMP and RRPD EDB EMP The following example shows what the same set of queries would look like if the publication was a snapshot only publication SQL gt CONNECT pubuser password Connected SON oh sPAGH Cen Ar ESO o 9 SQL gt SELECT table name FROM user tables TABLE NAME ICATION TABLES TXSET TON SUBSCRIPTIONS ET LOG 4 ee ee ee ee D W E U iO 7 to word cot p E 5 Q Z 2 ral Ss PUB_GROUP ERTIES XSET HEALTH Sa U 25 O U Sea ee aaa amp i alt ve pas 0 rows selected SQL gt SELECT sequence name FROM user sequences RREP_TXSET SEQ RREP_ COMMON SEQ Copyright 2012 EnterpriseDB Corporation All rights reserved 387 Postgres Plus xDB Replication Server with Multi Master User s Guide SQL gt
154. blication database It removes the identity and association of these tables to xDB Replication Server so the tables remain in the database until the DBA deletes them with the DROP TABLE SQL statement The publication database user name is also left intact along with some of the xDB Replication Server metadata database objects Shadow tables and triggers associated with the publication tables that were created by the publication server are deleted when the publication is removed The remaining metadata database objects are deleted when the publication database definition is removed Copyright 2012 EnterpriseDB Corporation All rights reserved 295 Postgres Plus xDB Replication Server with Multi Master User s Guide Step 1 Make sure the publication server whose node is the parent of the publication you wish to remove is running and has been registered in the xDB Replication Console you are using See Section 5 2 1 for directions on starting and registering a publication server Step 2 For SMR only Select the Publication node of the publication that you wish to remove Step 2 For MMR only Select the Publication node under the Publication Database node representing the master definition node eplication Servers Ei eS Publication Server 192 168 2 7 9051 GBa SMR QW Oracle 192 168 2 6 1521 xe pubu og E EDB DEPT E EDB EMP ia MMR S E Subscription Server 192 168 2 7 9052 EN R Postgres Plus Advanced Server
155. blication server and a subscription server and contains an xDB Control database The xDB Replication Console on each host can access and manage the replication systems on the other host if given the network IP address port number user name and password with which the publication server and subscription server were installed with on the remote host See Chapter 4 for information on the user interface of the xDB Replication Console 2 3 1 6 xDB Replication Server Command Line Interface XDB Replication Server Command Line Interface CLI is a command line driven alternative to the xDB Replication Console graphical user interface providing equivalent functionality for creating and controlling all aspects of a replication system Automation of replication system operations can be done by embedding xDB Replication Server CLI commands in scripts such as Bash for Linux xDB Replication Server CLI is installed whenever you choose to install the xDB Replication Console Chapter 8 provides directions for using xDB Replication Server CLI Copyright 2012 EnterpriseDB Corporation All rights reserved 31 Postgres Plus xDB Replication Server with Multi Master User s Guide 2 3 1 7 Publication Database The publication database contains the tables and views used in a publication The publication database may be running on the same host or on a different host than where the publication server is running as long as the hosts are accessible to eac
156. blication_name Are Up To Date appears click the OK button If an error appears determine which tables were changed and what changes were made to the table definitions These issues need to be resolved on a case by case basis as discussed earlier in this section Copyright 2012 EnterpriseDB Corporation All rights reserved 291 Postgres Plus xDB Replication Server with Multi Master User s Guide File Publication Subscription Help 7 7 Se LE 5 S CGE CHT g Replication Servers 5 amp Publication Server 192 168 2 4 9051 lt General Realtime Monitor Replication History B Ba SMR Property a R Postgres Plus Advanced Server 1 Publication schema edb oy Table count 2 E edb dept Subscription count 1 E edb emp A MMR E Subscription Server 192 168 2 4 9052 Information Q All schema of published tables in Publication sales_dept are up to date n Figure 216 Successful validation of all tables in the selected publication 7 5 4 2 Validating All Publications All publications under a single Publication Database node can be validated in one operation Note In a multi master replication system publication tables in only the master definition node are validated The validation operation does not check if table definitions have changed in other master nodes Step 1 Make sure the publication server whose node is the parent of the publications you wish to validate is runni
157. bordinate to the MMR type node of a given publication server identifies a master node in a single multi master replication system Note Currently there can only be one multi master replication system per publication server Section 5 2 2 discusses creating a publication database definition for a single master replication system See sections 6 2 2 and 6 3 for a multi master replication system 2 3 2 4 Publication Subordinate to a publication database definition in a single master replication system one or more publications can be defined A publication contains a list of tables and views that are to be replicated to a subscription database In a single master replication system the database user name specified in the publication database definition of the publication s parent as viewed in the replication tree must have the SELECT object privilege on any table or view that is to be included in the publication Subordinate to a publication database definition in a multi master replication system one and only one publication can be defined The publication contains the list of tables that are to be replicated and kept synchronized in the master nodes of the multi master replication system In a multi master replication system the database user name specified in the publication database definition of the publication s parent as viewed in the replication tree must have superuser privileges and be the owner of all table
158. bscription server identified by the content of file subsvrfile prop java jar edb repcli jar printsubdbidsdetails Ss repsvrfile subsvrfile prop Printing subscription database ids with details id host port database sid user BIA WSs Aq OS 2e eS U DUSESE 2 192 168 2 7 5444 subdb subuser 8 3 29 Updating a Subscription Database updatesubdb For SMR only The updatesubdb command provides the ability to change the connection information for an existing subscription database definition identified by its subscription database ID Copyright 2012 EnterpriseDB Corporation All rights reserved 352 Postgres Plus xDB Replication Server with Multi Master User s Guide Synopsis updatesubdb repsvrfile subsvrfile subdbid dbid dbhost host dbport port dbuser user dbpassword encrypted pwd dbpassfile pwdfile oraconnectiontype sid servicename database dbname The subscription database definition to be updated is identified by the subdbid parameter See Section 5 3 2 for details on the database connection information that must be supplied for a subscription database definition Parameters subsvrfile The file containing the subscription server login information dbid The subscription database ID of the subscription database definition to be updated host The IP address of the host on which the subscription database server is running port The port number on which the database server is listen
159. bscription Database node as the existing subscription that you do not want to remove Associate the new subscription with the new publication See Section 5 3 3 for directions to add a subscription e If your original publication and subscription use scheduled replication you would probably want to add a schedule to the new publication and subscription See Section 7 1 for directions to add a schedule If you choose the method of adding the tables to the original publication the following are the steps to add tables to an existing publication Note The following steps apply to multi master replication systems as well Step 1 Make sure the publication server whose node is the parent of the publication you wish to change is running and has been registered in the xDB Replication Console you are using See Section 5 2 1 for directions on starting and registering a publication server Step 2 For SMR only Select the Publication node of the publication to which you wish to add tables Step 2 For MMR only Select the Publication node under the Publication Database node representing the master definition node Copyright 2012 EnterpriseDB Corporation All rights reserved 267 Postgres Plus xDB Replication Server with Multi Master User s Guide ts Replication Servers oe Publication Server 192 168 2 7 9051 BS SMR GQ Oracle 192 168 2 6 1521 xe pubus s9 H EE EDB DEPT H E EDB EMP o i GA MMR A Subscription Server 192 168 2 7 90
160. bscription node Tabs labeled General Realtime Monitor and Replication History appear Copyright 2012 EnterpriseDB Corporation All rights reserved 235 Postgres Plus xDB Replication Server with Multi Master User s Guide S Oracle 192 168 2 6 1521 xe pubu H E EDB DEPT H E EDB EMP S Subscription Server 192 168 2 7 9052 S O Postgres Plus Advanced Server 192 Figure 161 Selecting a subscription on which to view replication history Step 1 For MMR only Select any Publication node under a Database node representing a master node Tabs labeled General Realtime Monitor Replication History and Conflict History appear Copyright 2012 EnterpriseDB Corporation All rights reserved 236 Postgres Plus xDB Replication Server with Multi Master User s Guide 5g Replication Servers E Publication Server 192 168 10 102 9051 3 sur Pa MMR GP Postgres Plus Advanced Server 1 3g EQ edb dept EE edb emp S Postgres Plus Advanced Server 1 emp_pub EE edb emp Figure 162 Selecting a publication on which to view replication history Step 2 Click the Replication History tab to show a history of replications Figure 163 Replication History tab Note Every snapshot replication and each synchronization replication with at least one update produces a history record that is maintained in replication history tables in the _edb replication pub schema of the xDB C
161. bstitute for pub_dbuser is the publication database user name you created in Step of Section 5 1 2 3 For a Postgres publication database named edb the resulting pg _hba conf file appears as follows TYPE DATABASE USER CIDR ADDRESS METHOD local is for Unix domain socket connections only local all all md5 IPv4 local connections host xdb enterprisedb 192 168 2 7 32 md5 host edb pubuser 192 LOB 2 T 32 md5 host all all 12 7 0 0 1 732 md5 IPv6 local connections host all a ele alias md5 Note The preceding example assumes the publication server and the subscription server are running on the same host hence the single entry for database edb If the publication server and subscription server are running on separate hosts each with its own xDB Control database then the pg_hba conf file on the publication database server would look like the following TYPE DATABASE USER CIDR ADDRESS METHOD Copyright 2012 EnterpriseDB Corporation All rights reserved 115 Postgres Plus xDB Replication Server with Multi Master User s Guide local is for Unix domain socket connections only local all all md5 IPv4 local connections host xdbpub enterprisedb 192 168 2 7 32 md5 host edb pubuser 19 16 Za If 32 md5 host edb pubuser 192 168 258 32 md5 host all all 127 Oo tly 32 md5 IPv6 local connections host anigi adhi 11 128 md5 Reload the configuration file after making the modificat
162. bsvr port The updatesub command allows you to update the subscription metadata consisting of the IP address and port number identifying the publication server that is the parent of the publication associated with the subscription This metadata is essential to the proper operation of the replication system since it is the means by which subscription server locates the publication server whenever a replication needs to be performed on a given subscription The replication process is always carried out by the publication server that manages the publication associated with the subscription You would use the updatesub command in the scenario where you have built your replication system using IP addresses that are valid at that point in time At some later point the IP address assigned to the host running the publication server has changed You use the host and port parameters of the updatesub command to supply the new network address identifying the publication server See Section 5 5 3 for additional information on updating a subscription Copyright 2012 EnterpriseDB Corporation All rights reserved 367 Postgres Plus xDB Replication Server with Multi Master User s Guide Parameters subname The name of the subscription whose metadata is to be updated subsvrfile The file containing the subscription server login information for the subscription server in which subscription subname was created pubsvrfile The file containing
163. buy Name DEPT H sales_dept Schema EDB ey PK attributes DEPTNO Ej EDB EMP Attributes count 3 3 MMR Fiter Clause E E Subscription Server 192 168 2 7 9052 Remove Filter Clause Q Fitter clause has been removed successfully _ Figure 214 Successful removal of the filter clause 7 5 4 Validating a Publication Once a publication is created do not directly change the definitions of the tables belonging to the publication Doing so may cause a failure during the replication process Examples of table definitions that must not be altered include Adding or removing columns to a table Renaming columns Changing the data types of columns Changing the lengths of columns Changing a not nullable column to nullable or a nullable column to not nullable Adding or removing uniqueness constraints Adding or removing check constraints In a single master replication system xDB Replication Server does not propagate table definition changes to the subscription tables once the subscription tables are created Rows that may be allowed in an altered publication table may be illegal in the unaltered subscription table and will cause an error during replication Similarly in a multi master replication system table definition changes are not propagated from one master node to another except when a new master node is added and you choose to replicate the schema definition from the master definition node Copyright 2012 Enterpr
164. byconflictresolution N Updating Primary Standby Conflict Resolution Strategy The Primary Standby conflict resolution strategies were updated successfully 8 3 21 Setting the Master Definition Node setasmdn For MMR only The setasmdn command sets a master node to the role of master definition node Synopsis setasmdn pubdbid repsvrfile pubsvrfile Copyright 2012 EnterpriseDB Corporation All rights reserved 344 Postgres Plus xDB Replication Server with Multi Master User s Guide See Section 6 9 for additional information on setting the master definition node Parameters pubdbid The publication database ID of the master node to be given the role of master definition node pubsvrfile The file containing the publication server login information Examples The following example sets the master node with publication database ID 9 as the master definition node S java jar edb repcli jar setasmdn 9 repsvrfile pubsvrfile prop Updating the database node to be promoted as the new MDN node The database has been successfully promoted as the new MDN node 8 3 22 Validating a Publication validatepub The validatepub command checks if any of the definitions of the tables in the given publication have changed since the publication was created Synopsis validatepub pubname repsvrfile pubsvrfile repgrouptype m s See Section 7 5 4 for additional information on validating publications Parameters pubna
165. case by case basis as discussed earlier in this section Copyright 2012 EnterpriseDB Corporation All rights reserved 294 Postgres Plus xDB Replication Server with Multi Master User s Guide File Publication Subscription Help S GJU CG ig Replication Servers k General e Publication Server 192 168 2 4 9051 Gs SMR Property amp R Postgres Plus Advanced Server 1 Host 192 168 2 3 Sy sales_dept Port 5444 Ea edb dept Database edb edb emp User pubuser F jobhist E edb jobhist A MMR fh Subscription Server 192 168 2 4 9052 Information The column structure for one or more tables in the following publications are changed in the source EnterpriseDB table schema Publication jobhist Figure 219 List of publications with modified tables 7 5 5 Removing a Publication In a single master replication system before a publication can be removed its associated subscription must be removed first See Section 5 5 4 for directions to remove a subscription In a multi master replication system the publication is removed from under the Publication Database node representing the master definition node Before a publication can be removed all master nodes other than the master definition node must be removed See Section 7 5 6 for directions to remove a publication database definition of a master node Removing a publication does not delete the publication tables in the pu
166. cation Server CLI both give you the capability to immediately start a replication This is called an on demand replication On demand replication can be performed at any time regardless of whether or not there is an existing schedule An on demand replication does not change the date and time when the next replication is scheduled to occur according to an existing schedule If a publication is a snapshot only publication then the only type of on demand replication that can be performed on this publication is a snapshot Copyright 2012 EnterpriseDB Corporation All rights reserved 57 Postgres Plus xDB Replication Server with Multi Master User s Guide If a publication is not a snapshot only publication you can perform an on demand replication using either the snapshot method or the synchronization method When you are in the development and testing phases of your replication system you would typically use on demand replication so that you can immediately force the replication to occur and analyze the results When your replication system is ready for production a schedule would typically be used so that replications can occur unattended at regular time intervals See Section 7 1 for directions on creating a schedule There may be other situations where you would want to force a replication to take place ahead of its normal schedule Reasons for performing an on demand replication may include the following e The number of changes
167. cation Servers General eS Publication Server 192 168 2 7 9051 E Subscription Server 192 168 2 7 9052 Properly G R Postgres Plus Advanced Server 192 1 Publication server 192 168 2 7 r S Publication server port 9051 Scheduled job status Not available Figure 101 Selecting a subscription to update Step 3 From the Subscription menu choose Update Subscription Alternatively click the secondary mouse button on the Subscription node and choose Update Subscription The Update Subscription dialog box appears Copyright 2012 EnterpriseDB Corporation All rights reserved 155 Postgres Plus xDB Replication Server with Multi Master User s Guide Figure 102 Update Subscription dialog box Step 4 If the publication server now runs on a host with a different IP address or port number than what is shown in the dialog box enter the correct information You must also enter the user name and password saved in the xDB Replication Configuration file that resides on the host on which the publication server is running Click the Update button Copyright 2012 EnterpriseDB Corporation All rights reserved 156 Postgres Plus xDB Replication Server with Multi Master User s Guide Update Subscription Subscription Name sales_dept_sub Publicatio Password 000800 Figure 103 Subscription successfully updated Step 5 If Subscription Updated Successfully appears click the OK button otherwise in
168. cations GRANT SELECT ON edb dept TO pubuser GRANT SELECT ON edb emp TO pubuser GRANT SELECT ON edb jobhist TO pubuser GRANT SELECT ON edb salesemp TO pubuser GO Step 8 For application database users added after the publication has been created For each application database user that is to modify the data in any of the application tables to be replicated by SQL INSERT UPDATE or DELETE statements privileges must be granted on the xDB Replication Server metadata database objects to these users In the following example new_user is a new database user that will be updating the application tables GRANT EXECUTE ON SCHEMA pubuser TO new user GRANT SELECT ON SCHEMA pubuser TO new_user GRANT INSERT ON SCHEMA pubuser TO new_user GO Note Instead of using the preceding statements which grant privileges at the schema level a more granular level of privileges can be issued at the database object level using the following statements GRANT EXECUTE ON pubuser nextval to new _ user Copyright 2012 EnterpriseDB Corporation All rights reserved 105 Postgres Plus xDB Replication Server with Multi Master User s Guide GRANT SELECT ON pubuser rrep tx _seq TO new_user GRANT INSERT ON pubuser rrep tx _seq TO new_user GRANT INSERT ON pubuser RRST edb dept TO new_user GRANT INSE
169. cccsssccsssssessscsssssncessnccessssesenacesenacesenaceesns 295 7 5 6 Removing a Publication Database cccssscscssscsessscssssccsensscessssessnsseeens 299 7 6 RepliQDDL Chante csc2ccen otters ese tia gn ee 302 7 6 1 DDL Change Replication Process ccsceesecceesceseeeceneencersereetsensontens 304 7 6 2 DDL Change Replication Using the xDB Replication Console 305 7 7 Loading Tables From an External Data Source Offline Snapshot 307 7 7 1 Non Batch Mode Synchronization 00 ce ee eeseceeeceeeeeeneeceaecseeeseeeeeaeesnaeens 308 7 1 2 Offline Snapshot Configuration Options 0 0 0 0 cee eeeeesecsneceeeeeeeeeeaeeeaeees 309 7 1 3 Single Master Replication Offline Snapshot 0 ee eee eeseceeeeeeeeereeeneeens 310 7 7 4 Multi Master Replication Offline Snapshot ee eee eeseceeeeeeeeereeeneeens 311 8 xDB Replication Server Command Line Interface eee eeeeseeceseeeeeeeeeeeenaeens 313 8 1 PHETEQUISIES SLEDS viciuavissasisaocacsndeavarsasersachaasncney EEA S EE REEE 313 8 2 General Usages rentin aA a pte a E Dison nannceaee 314 8 2 1 Running xDB Replication Server CLI eesesseseeeesreeresressesererressereresreeseree 314 Copyright 2012 EnterpriseDB Corporation All rights reserved 6 Postgres Plus xDB Replication Server with Multi Master User s Guide 8 2 2 Getting Help iiiuns ina siin n E E a i sia 315 8 2 3 Supplying the Publication or Subscription Server Login Information
170. ced Server 192 192 168 2 7 Port 5444 Database subdb User subuser Figure 100 Updated subscription database Copyright 2012 EnterpriseDB Corporation All rights reserved 154 Postgres Plus xDB Replication Server with Multi Master User s Guide 5 5 3 Updating a Subscription When a subscription is created certain attributes of the subscribed publication are stored as part of the metadata for the subscription in the xDB Control database These include the following e The network IP address of the host running the publication server that is the parent of the subscribed publication e The port number of the publication server If the preceding attributes of the publication server change in the replication system environment then the corresponding subscription metadata must also be changed so the subscription server can communicate with the correct publication server The following directions show how to update the publication server network IP address and port number within the subscription server s metadata Step 1 Make sure the subscription server whose node is the parent of the subscription you wish to change is running and has been registered in the xDB Replication Console you are using See Section 5 3 1 for directions on starting and registering a subscription server Step 2 Select the Subscription node whose attributes you wish to update File Publication Subscription Help Cg Eakas g Repli
171. cheduling of shadow table history cleanup on an Oracle publication database the Oracle DBMS_JOB package on the Oracle database server is used The time you specify in the schedule for cleanup is passed and stored in DBMS_JOB without time zone translation For example assume the publication server is running on a host in New York and the Oracle publication database is on a server in California which has a 3 hour time difference If you set shadow table history cleanup to run at 12 00 AM midnight according to the New York based publication server the cleanup job on the California based Oracle database will start at 12 00 AM midnight Pacific Time in California which would be 3 00 AM Eastern Time in New York For SQL Server only For scheduling of shadow table history cleanup on a SQL Server publication database SQL Server Agent is used on the host running SQL Server The time you specify in the schedule for cleanup is passed to SQL Server Agent without time zone translation The effect is the same as described for Oracle in the preceding example For Postgres only For scheduling of shadow table history cleanup on a Postgres publication database the Quartz scheduler is used on the host running the publication server For example assume the publication server is running on a host in New York and the Postgres publication database is on a host in California If you set shadow table history cleanup to run at 12 00 AM midnight accor
172. choose but only on the specific days of the week you choose Select this option if you need more flexibility than a daily schedule and the target tables do not have to be refreshed every day e Monthly Schedules replication to run one day per month on the day of the month and time you choose but only on the specific months you choose Select this option if updates to the source tables are not very frequent and the target tables can be out of date by a month or more The Monthly option allows you to schedule replication for as frequently as once a month or infrequently as once a year e Cron Expression Provides additional flexibility for specifying a schedule beyond the four preceding radio button choices See appendix Section 9 3 3 for directions on writing a cron expression Copyright 2012 EnterpriseDB Corporation All rights reserved 225 Postgres Plus xDB Replication Server with Multi Master User s Guide The following example shows the selection of a weekly schedule ted schedule will appear Click the Finish button to accept the schedule gt y Copyright 2012 EnterpriseDB Corporation All rights reserved 226 Postgres Plus xDB Replication Server with Multi Master User s Guide Schedule Summary Task Synchronize The job will be scheduled to execute every week at 01 00 AM On following day s Monday Wednesday Friday Sunday Figure 149 Scheduled Task Wizard summary If you click the Refr
173. containing the ALTER TABLE statements you wish to apply to a publication table Make sure this text file is accessible by the operating system account with which you will open the xDB Replication Console Step 2 Make sure the publication server whose node is the parent of the publication containing the table you wish to change is running and has been registered in the xDB Replication Console you are using See Section 5 2 1 for directions on starting and registering a publication server Step 3 Open the Alter Publication Table dialog box by clicking the secondary mouse button on the Table node of the table to be modified and choose Alter Table File Publication Subscription Help tq Replication Servers amp Publication Server 192 168 2 7 9051 MMR j Postgres Plus Advanced Server 1 amp g emp_pub Attributes count Conflict Resolution Standby Conflict Resolution Filter Clause Figure 227 Selecting a table to alter Step 4 In the Alter Publication Table dialog box browse for the text file containing the ALTER TABLE statements and click the OK button Copyright 2012 EnterpriseDB Corporation All rights reserved 305 Postgres Plus xDB Replication Server with Multi Master User s Guide Tobe Nane SQL Script File red Folders Documents addcolumn sql Figure 228 Alter Publication Table dialog box Step 5 If the DDL replicated successfully message box appears the DDL change was success
174. cription database connection cannot be removed as one or more subscriptions are defined against it Resolution You cannot remove a subscription database definition if there are subordinate subscriptions Remove the subscriptions first Subscription does not exist on the subscription service It might have been removed by some other user Resolution The Subscription node you are trying to select no longer represents an existing subscription The subscription may have been removed by a concurrent xDB Replication Console or xDB Replication Server CLI session Click the Refresh icon in the xDB Replication Console toolbar to display the current replication tree Subscription Service connection failure Resolution Verify that the subscription server is running See Section 9 2 4 1 A table with large object type PK attribute cannot be published for synchronize incremental replication Resolution Oracle doesn t log changes for a large object column Such a column cannot be referenced in the triggers that log changes to the shadow tables Use snapshot only replication instead a Test result Failure Database connection information test failed Reason Connection refused Check that the hostname and port are correct and that the postmaster is accepting TCP IP connections Resolution Occurs when testing the connection of a publication or subscription database definition The publication or subscription server cannot connect to th
175. curs serially For example in a 3 node replication system where node A is the master definition node along with additional master nodes B and C the pending transactions available on node A are replicated to node B and then to node C Node B s pending transactions are then replicated to Node A and Node C Finally Node C s pending transactions are replicated to Node A and Node B Using this 3 node example the following describes the conflict detection process in more detail e The replication server loads the first set of pending transactions from master node A Transactions are processed on a transaction set basis The same process is used for single master replication All pending transactions are grouped in one or more transaction sets to avoid loading a very large chunk of rows in memory that may result in an out of heap space issue e For an update transaction the replication server queries the first target master node B to load the related row If the old column value on the source master node A is different than the current column value on target master node B the transaction is marked as an update conflict If a related row is not found on the target master node it is marked as an update delete conflict e Fora delete transaction the replication server queries the target master node to load the related row If a related row is not found on the target master node the transaction is marked as a delete delete conflict e When
176. d and the xDB Control database cannot be salvaged from that node or restored from Copyright 2012 EnterpriseDB Corporation All rights reserved 166 Postgres Plus xDB Replication Server with Multi Master User s Guide a backup then performing a failover is not possible A reconfiguration is necessary using the subscription database as the new publication database For this reason it is strongly urged to take periodic backups of the xDB Control database e Ifthe metadata database objects on the publication database that is schema _edb replicator pub and its objects cannot be salvaged or restored from a backup then performing a failover may be possible with the assistance of EnterpriseDB Technical Support Services e Pending updates not yet applied to the subscription may have been lost The chances of this are greater if the interval between synchronizations is long If you determine that a failover is possible follow the steps for a controlled switchover 5 8 Optimizing Performance Once you have become familiar with setting up and managing your replication system you will often look for ways to optimize the performance of replications This section discusses various publication server and subscription server configuration options available to improve the performance of snapshot and synchronization replications The publication server and subscription server configuration options are set in the publication server and subscription s
177. d by pubname 1s specified If the command acts on a subscription the subscription name represented by subname is specified Certain commands may allow the specification of more than one publication name or more than one subscription name Depending upon the command one or more parameters may follow Each parameter name must have a hyphen prefix You may need to specify one or more values for each given parameter If a command takes more than one parameter the order in which the parameters are specified makes no difference Each parameter must be followed only by the values that pertain to it Command names and parameter names are all case sensitive and must be given as shown in Section 8 3 The general complete execution syntax that you enter at the command line prompt has the following format java jar XDB HOME bin edb repcli jar command pubname subname parameter value The preceding syntax must be entered as one logical line on the command line It is broken up into multiple lines in the preceding syntax diagram for the purpose of clarity Note You can continue a command onto the next physical line if you enter the operating system s continuation character for example the backslash character in Linux or the caret character in Windows before pressing the Enter key 8 2 2 Getting Help If you execute the xDB Replication Server CLI with the help command xDB Replication Server CLI will l
178. d has finished The downloaded files have been retained to allow future installations or upgrades some packages require the original installation files when being upgraded You may run this wizard again at any time to add to or upgrade the software in your stack If you wish to remove any software please use the Add Remove Programs Control Panel applet tora SaL Company Figure 48 StackBuilder Plus installation complete Successful installation of xDB Replication Server affects your host environment as described in Section 3 2 3 2 Post Installation Host Environment On Linux hosts you should now have a publication server daemon and a subscription server daemon running on your computer assuming you chose to install the publication server and subscription server components On Windows systems the publication server and subscription server run as services named Publication Service and Subscription Service An xDB Control database will have been created if it did not already exist The Postgres application menu contains a new item for the xDB Replication Console Note On some Linux systems you may have to restart the server before you can see the xDB Replication Console choice in the application menu Copyright 2012 EnterpriseDB Corporation All rights reserved 86 Postgres Plus xDB Replication Server with Multi Master User s Guide The following files are created that you may need during the configuration process Tab
179. d successfully Publication Database id 1 The following example adds a publication database definition for an Advanced Server database The encrypted password is read from a file named pwdfile with the dbpassfile parameter A publication database ID of 2 is assigned to the database by the publication service S java jar edb repcli jar addpubdb repsvrfile pubsvrfile prop gt dbtype enterprisedb dbhost 192 168 2 7 dbport 5444 gt dbuser pubuser dbpassfile pwdfile gt database edb gt repgrouplype Adding Publication Database Publication database added successfully Publication Database id 2 The following example adds a publication database definition for a master definition node in a multi master replication system S java jar edb repcli jar addpubdb repsvrfile pubsvrfile prop dbtype enterprisedb dbhost 192 168 2 6 dbport 5444 gt dbuser pubuser dbpassword ygJ9AxoJEX854elcVIJPTw gt gt gt database edb repgrouptype m nodepriority 1 Adding Publication Database Replicating publication schema Publication database added successfully Publication Database id 6 The following example adds a publication database definition for a master node other than the master definition node in a multi master replication system where an initial snapshot is not invoked the initialsnapshot parameter is omitted and a node priority level of 3 is assigned to the master node Note A
180. d times The Linux cron tool uses a cron expression to schedule the execution of a job xDB Replication Server uses the Quartz job scheduling system for scheduling replications When creating a schedule for an xDB Replication Server replication system a cron expression can be specified There are a number of formats for cron expressions You must use the cron expression format supported by Quartz The remainder of this section provides an overview of most of the types of cron expressions that can be used for an xDB Replication Server schedule For a more comprehensive treatment of cron expressions refer to the Quartz documentation A Quartz cron expression consists of six mandatory fields followed by one optional field Each field is separated from its neighbors by one or more consecutive space characters The fields are order dependent and are listed as they must appear below ss mi hr dd mm dow yyyy Table 9 Cron Expression Fields 0 59 Mime of the hour 1 310r Day of the month if dow is given then dd must be specified as mm 1 12 or JAN DEC Month of the year 3 letter month abbreviations are not case sensitive Day of the week if dd is given then dow must be specified as 3 dow 1 7 or SUN SAT or ee ps letter day of the week abbreviations are not case sensitive 1970 2099 Year if omitted then any year applies Copyright 2012 EnterpriseDB Corporation All rights reserved 404
181. data source Resolution Occurs when creating an Oracle publication or subscription database definition Copy the Oracle JDBC driver file 0jdbc14 jar to subdirectory 1ib jdbc of where the publication server or subscription server is installed on the host running the publication server or subscription server Restart the publication server or subscription server One or more subscriptions are defined against this publication Removing the publication will invalidate the subscription Resolution Warning issued when you attempt to remove a publication with subscriptions associated with it You can remove the publication but the subscriptions are no longer usable and should be removed as well Only subscription which has subscribed against a publication with transactional replication type can be synchronized Resolution You cannot perform synchronization replication on a snapshot only publication Perform snapshot replication instead Parent table table name is not selected when its child tables are part of the publication list Resolution Table selected for a publication has a foreign key referencing a parent table that has not been chosen for the publication This is only a warning that the parent table will not be part of the subscription Problem occurred in publish process Reason ERROR permission denied for schema _edb replicator pub Resolution Fora Postgres publication verify that the publication database us
182. database user name subuser is specified in the definition along with the database network location and database identifier e A subscription named sub is created subordinate to the subscription database definition When the subscription is created the subscription server creates schemas named S1 and S2 in the subscription database The table definitions for tables A B and C are also created at this time When replication occurs the publication server populates these tables with rows from the publication The following screen capture shows how the logical components of this replication system appear in the xDB Replication Console replication tree Copyright 2012 EnterpriseDB Corporation All rights reserved 41 Postgres Plus xDB Replication Server with Multi Master User s Guide LO xDB Replication Ca a BBwy OG ba Replication Servers Publication Server 192 168 2 3 9051 B B SMR B av SQL Server 192 168 2 3 1433 pubdb pubuser 2H pub G E st a EE s2 b H E s2 c A fa MMR tg Subscription Server 192 168 2 3 9052 B Postgres Plus Advanced Server 192 1638 2 3 5444 subdb subuser bg sub aeg pub EE s1 a GF s2 b H E s2 c Figure 14 SQL Server to Postgres replication tree See Chapter 4 for an introduction to the xDB Replication Console 2 3 3 3 Postgres Plus Advanced Server to Oracle Replication The following is an illustration of a basic Postgres Plus Advanced Server to Oracle single
183. dding the additional tables you must perform the following steps e Remove the subscription that is associated with the publication See Section 5 5 4 for directions to remove a subscription e Remove the subscription tables from the subscription database This is done with the SQL DROP TABLE statement in the database system e Add the tables to the publication See the following steps in this section e Re add the subscription See Section 5 3 3 for directions to add a subscription Copyright 2012 EnterpriseDB Corporation All rights reserved 266 Postgres Plus xDB Replication Server with Multi Master User s Guide In the aforementioned method the entire publication must be replicated after the new tables are added to the publication If there are large subscription tables associated with the original publication that you do not want to delete and replicate again in their entirety create a new publication and subscription containing only the additional tables that you want to replicate Adding a second publication and subscription leaves your original publication and its subscription intact and unchanged Perform the following to create a new publication and subscription for the additional tables e Add anew publication containing the additional tables under the same Publication Database node as the original publication See Section 5 2 3 for directions to add a publication e Add a new subscription under the same Su
184. de Set this option to true if you want the publication table definitions replicated from the master definition node when creating a new master node Set this option to false if you have already created the table definitions in the new master node If omitted the default is true Do not specify this parameter when creating the master definition node initialsnapshot For MMR only Applies to master nodes other than the master definition node Specify this option if you want an initial snapshot replication to be performed when creating the master node priority level For MMR only Integer value from 1 through 10 assigning the priority level to a master node with having the highest priority and 10 having the lowest priority Copyright 2012 EnterpriseDB Corporation All rights reserved 323 Postgres Plus xDB Replication Server with Multi Master User s Guide Examples The following example adds a publication database definition for an Oracle database The encrypted password is given on the command line with the dbpassword parameter A publication database ID of 1 is assigned to the database by the publication service S java jar edb repcli jar addpubdb repsvrfile pubsvrfile prop gt Clevioa Oracle dbhos t 92 6256 E peor 1521 dbuser pubuser dbpassword ygJ9AxoJEX854elcVIJUPTw gt gt gt oraconnectiontype sid database xe repgroupLlype Adding Publication Database Publication database adde
185. ded during replication All other rows are excluded from the replication A filter is expressed as a text string called a filter clause A filter clause is equivalent to the WHERE clause of a SQL SELECT statement See Section 7 5 3 3 for information on the filter clause Copyright 2012 EnterpriseDB Corporation All rights reserved 23 Postgres Plus xDB Replication Server with Multi Master User s Guide 2 3 XDB Replication Server Components and Architecture This section describes the components and architecture of xDB Replication Server Section 2 3 1 describes the executable programs files and databases that comprise xDB Replication Server Section 2 3 2 defines the logical components of a replication system and how they correspond to the programs and databases Section 2 3 3 illustrates some examples of replication systems 2 3 1 Physical Components xDB Replication Server is not a single executable program but rather a set of programs along with datastores containing configuration information and metadata that work together to form a replication system The following diagram illustrates the components of xDB Replication Server and how they are used to form a complete basic single master replication system Copyright 2012 EnterpriseDB Corporation All rights reserved 24 Postgres Plus xDB Replication Server with Multi Master User s Guide replication syste xDB Replication Console or xDB Re
186. default value is LAZY skipConflictDetection The skipConflictDetection option controls whether or not to skip conflict detection during synchronization replication The default is false and should be changed only when the probability of data conflict across master nodes is zero For example if each master node operates on an independent set of data then turning on this option improves the replication time skipConflictDetection true false The default value is false Copyright 2012 EnterpriseDB Corporation All rights reserved 220 Postgres Plus xDB Replication Server with Multi Master User s Guide 7 Common Operations This chapter describes configuration and maintenance operations of xDB Replication Server that are common to both single master and multi master replication systems For configuration and management of your replication system the xDB Replication Console graphical user interface is used to illustrate the steps and examples in this chapter The same steps can be performed from the operating system command line using the xDB Replication Server Command Line Interface CLI The commands of the xDB Replication Server CLI utility are described in Chapter 8 Note Though most steps described in this chapter apply to both single master and multi master replication systems those steps that apply only to single master replication systems are noted with For SMR only Those steps that apply only to multi master replication
187. definition node a database user name must be specified that has the following characteristics e The database user can connect to the master definition node e The database user has superuser privileges e The database user must have the ability to modify the system catalog tables in order to disable foreign key constraints on the publication tables See appendix Section 9 3 4 for more information on this requirement The examples used throughout the rest of this user s guide are based on the following master definition node e The database user name for the master definition node is pubuser e The tables used in the publication reside in a schema named edb e Three tables named dept emp and jobhist are members of schema edb e The database name of the master definition node is edb The following steps illustrate the preparation of the master definition node database user Step 1 Create a user name with login and superuser privileges for the master definition node This user becomes the owner of xDB Replication Server metadata database objects that will be created in the master definition node to track control and record the Copyright 2012 EnterpriseDB Corporation All rights reserved 178 Postgres Plus xDB Replication Server with Multi Master User s Guide replication process and history The xDB Replication Server metadata database objects are created ina schema named edb replicator pub When creating the publication da
188. describe how to create a subscription from an offline snapshot Step 1 Register the publication server add the publication database definition and create the publication as described in Section 5 2 Step 2 Register the subscription server and add the subscription database definition as described in sections 5 3 1 and 5 3 2 respectively Copyright 2012 EnterpriseDB Corporation All rights reserved 310 Postgres Plus xDB Replication Server with Multi Master User s Guide Note Steps 3 and 4 must be performed before creating the subscription Steps 3 through 9 can be repeated each time you wish to create an additional subscription from an offline snapshot Step 3 Modify the publication server configuration file if these options are not already set as described by the following e Change the of flineSnapshot option to true When the publication server is restarted of flineSnapshot set to true has the effect that 1 creating a subscription does not create the schema and subscription table definitions in the subscription database as is done with the default setting and 2 creating a subscription sets a column in the xDB Control database indicating an offline snapshot is used to load this subscription e Set the batchInitialSync option to the appropriate setting for your particular situation as discussed at the end of Section 7 7 1 Step 4 Restart the publication server if the publication server configuration file was modified in
189. ding to the New York based publication server the cleanup job on the California based Postgres database will start at 12 00 AM midnight Eastern Time in New York which would be 9 00 PM Pacific Time in California Copyright 2012 EnterpriseDB Corporation All rights reserved 243 Postgres Plus xDB Replication Server with Multi Master User s Guide For Oracle only The cleanup job on an Oracle publication database runs independently of the publication server so the cleanup job will run regardless of whether or not the publication server is running For Postgres only The publication server must be running in order for the cleanup job to run on a Postgres publication database Note An alternative to using the Quartz scheduler when Postgres is the publication database is to use pgAgent job scheduling instead See Section 9 3 1 7 for information on how to use pgAgent job scheduling and the advantages thereof The following steps show how to alter the default setting Step 1 Make sure the publication server whose node is the parent of the publication database definition whose cleanup scheduling preference you want to set is running and has been registered in the xDB Replication Console you are using See Section 5 2 1 for directions on starting and registering a publication server Step 2 Select the Publication Database node for which you want to set the cleanup scheduling preference ta Replication Servers GH Publicati
190. e 233 User with privilege to update system catalogs Copyright 2012 EnterpriseDB Corporation All rights reserved 406 Postgres Plus xDB Replication Server with Multi Master User s Guide If the Update Catalogs property is set to No click the secondary mouse button on the user name in the Object Browser and choose Properties from the menu Select the Role Privileges tab check the Can Modify Catalog Directly box and click the OK button Properties Definition Role privileges Role membership Variables soL Can login W Inherits rights from parent roles W Superuser F Can create database objects Can create roles Can modify catalog directly V Can initiate streaming replication and backups Figure 234 Granting system catalog update privilege 9 3 5 Quoted Identifiers and Default Case Translation A quoted identifier is an identifier created with its name enclosed within double quote characters The text enclosed within double quotes is stored as the object identifier name exactly as given with no default case translation of alphabetic characters Quoted identifiers occur in both Oracle and Postgres Copyright 2012 EnterpriseDB Corporation All rights reserved 407 Postgres Plus xDB Replication Server with Multi Master User s Guide For example CREATE TABLE MyTable produces a table name that is stored in the database syste
191. e Database Servers The following sections describe configuration steps required to use xDB Replication Server on various types of database servers The following section describes the steps to enable access to Oracle See Section 5 1 1 2 for enabling access to SQL Server No special steps are required to enable access to a Postgres database server 5 1 1 1 Enabling Access to Oracle Note The directions in this section apply only if Oracle will be used as the publication or subscription database The JDBC driver for Oracle ojdbc14 jar must be accessible to the Java virtual machine JVM on the host running the publication server and the subscription server If the publication server and subscription server are running on separate hosts an ojdbc14 jar file must be accessible to the JVM on each host Step 1 Download the Oracle JDBC driver 03 dbc14 ar from the Oracle download site to the host that will be running the publication server Step 2 Copy file ojdbc14 jar to the directory XDB_HOME 1ib jdbc Copyright 2012 EnterpriseDB Corporation All rights reserved 99 Postgres Plus xDB Replication Server with Multi Master User s Guide The following is an example when xDB Replication Server is installed in the same directory where Postgres is installed that is XDB_ HOME is equivalent to POSTGRES_ INSTALL HOME S Sui root Password S cd opt PostgresPlus 9 1AS lib jdbe S cp home user Downloads ojdbcl4 jar S i
192. e Update Publication then Remove Tables Copyright 2012 EnterpriseDB Corporation All rights reserved 275 Postgres Plus xDB Replication Server with Multi Master User s Guide e Click the secondary mouse button on the Publication node choose Update Publication and then choose Remove Tables e Click the primary mouse button on the Remove Publication Tables icon S xDB Replication Cons Oracle 192 168 2 6 1521 xe pubus BE Ties cer H E EDB DEPT H E EDB EMP EE EDB JOBHIST of MMR tg Subscription Server 192 168 2 7 9052 AR Postgres Plus Advanced Server 192 1 Subscription count Figure 202 Opening the Remove Tables dialog box by clicking the toolbar icon Step 4 Check the boxes next to the table and view names from the Available Tables list that are to be removed from the publication Copyright 2012 EnterpriseDB Corporation All rights reserved 276 Postgres Plus xDB Replication Server with Multi Master User s Guide lick the Yes button of the confirmation box Copyright 2012 EnterpriseDB Corporation All rights reserved 277 Postgres Plus xDB Replication Server with Multi Master User s Guide pathove Tobie Poblacetsan sales dept a d T A Click the OK button in respo Copyright 2012 EnterpriseDB Corporation All rights reserved 278 Postgres Plus xDB Replication Server with Multi Master User s Guide R ftiove Tables Publication sales dep
193. e by the following entry host all all 127 050 1 32 md5 The following example shows the pg_hba conf file for a configuration where the publication server and subscription server are running on the same host using the same xDB Control database on the host TYPE DATABASE USER CIDR ADDRESS METHOD local is for Unix domain socket connections only local all ull IL md5 IPv4 local connections host xdb enterprisedb 192 168 2 7 32 md5 host all all 127 0 05 1 32 md5 IPv6 local connections host aniti anii mag md5 If the publication server and subscription server are running on separate hosts each with their own xDB Control database then modifications must be made to the pg_hba conf file on each database server running an xDB Control database as shown by the following example where xdbpub is the xDB Control database on the publication server and xdbsub is the xDB Control database on the subscription server On the publication server 192 168 2 7 TYPE DATABASE USER CIDR ADDRESS METHOD local is for Unix domain socket connections only Toca ull iL gull iL md5 IPv4 local connections host xdbpub enterprisedb 192 168 2 7 32 md5 host all all IDF O O 1 7 32 md5 Copyright 2012 EnterpriseDB Corporation All rights reserved 113 Postgres Plus xDB Replication Server with Multi Master User s Guide IPv6 local connections host all all ESIZ md5 Note For a database server whos
194. e database The pooling framework is used to cache the connections After the threads are finished with the data load the idle connections are returned to the pool and remain there for a period of 3 minutes before being removed from the pool as long as these are not reused e Changes are applied to multiple target databases in parallel A transaction set from the source database is loaded only once The target databases are updated in parallel from this loaded transaction set When this transaction set has been applied to all targets either successfully or with failures on some targets the next transaction set is loaded and applied in parallel This aspect of parallel synchronization is particularly relevant to multi master replication systems The following configuration options affect the usage of parallel synchronization syncLoadThreadLimit The syncLoadThreadLimit option controls the maximum number of threads used to load data from source publication tables during parallel synchronization The default count is 4 However depending on the target system architecture specifically multi CPUs cores you can choose to specify a custom count normally equal to the CPU core count to fully utilize the system resources syncLoadThreadLimit n The default value is 4 targetDBQueryTimeout Copyright 2012 EnterpriseDB Corporation All rights reserved 174 Postgres Plus xDB Replication Server with Multi Master User s Guide The targetDB
195. e database identified by the subscription database definition Step 1 Select the Subscription Database node From the Subscription menu choose Create Subscription Alternatively click the secondary mouse button on the Subscription Database node and choose Create Subscription The Create Subscription dialog box appears Step 2 Fill in the following fields e Subscription Name Enter a name for the subscription that is unique amongst all subscription names e Host Network IP address of the publication server that is the parent node of the publication to be subscribed to This is the same value entered in the Host field in Step 3 of Section 5 2 1 e Port Port used by the publication server This is the same value entered in the Port field in Step 3 of Section 5 2 1 e User Name User name of the publication server This is the same value entered in the User Name field in Step 3 of Section 5 2 1 e Password Password of the user This is the same value entered in the Password field in Step 3 of Section 5 2 1 e Publication Name Click the Load button to get a list of available publications Select the publication to which to subscribe Copyright 2012 EnterpriseDB Corporation All rights reserved 137 Postgres Plus xDB Replication Server with Multi Master User s Guide Figure 81 Create Subscription dialog box Step 3 Click the Create button If Subscription Created Successfully appears click the OK button otherwise investig
196. e database server network location given in the Add Database dialog box Verify that the correct IP address and port for the database server are given Verify that the database server is running and is accessible from the host running the publication or subscription server Test result Failure Database connection information test failed Reason FATAL no pg_hba conf entry for host Xxx xXxXx xxX xXxXx user user name database db name SSL off Resolution Occurs when testing the connection of a publication or subscription database definition Verify that the database host IP address port number database user name password and database identifier are correct Verify that the database server is running For a Postgres database verify there is an entry in the pg_hba conf file permitting access to the database by the given user name originating from the IP address where the publication server or subscription server is running Unable to create Subscription subscription name Reason Connection rejected FATAL no pg_hba conf entry for host xxx xxx xxx xxx user user name database db name SSL off Resolution Occurs when creating a subscription The subscription server running on host xxx xxx xx xxx Could not access the xDB Control database Verify that the pg_hba conf file on the xDB Control database server permits access from the subscription server host Unable to create subscription schema tables Org postgresql util PSQLExcepti
197. e eeeeeeeeeeeeeeteeee 352 Copyright 2012 EnterpriseDB Corporation All rights reserved 7 Postgres Plus xDB Replication Server with Multi Master User s Guide 8 3 30 Removing a Subscription Database removesubdD eeeeeeeeeeeeeeteees 354 8 3 31 Creating a Subscription CrEALESUD ss sasteccseveeccvsassncensesderadeuonteesaatenbedacdonaeans 355 8 3 32 Printing a Subscription List printsublist 0 eee eeeseceeeeceeeeeeeeeeeeeseees 356 8 3 33 Taking a Single Master Snapshot dosnapshot c cceeeseeceeeeeeeeeeeeeeees 357 8 3 34 Take a Multi Master Snapshot dommrsnapshot cesseeceeeeeeeeeeeeteees 358 8 3 35 Performing a Synchronization dosynchronize csceceeceeceeeeeeteeeeeteees 359 8 3 36 Configuring a Single Master Schedule confschedule eee eeeeeeeeeteees 361 8 3 37 Configuring a Multi Master Schedule confschedulemm1 008 363 8 3 38 Print Schedule printschedule a2 scccsscissvn tars avecduaderssseapabeee seiassegaatiausancageceatas 365 8 3 39 Updating a Subscription updatesub eee eaeeeeneeceeeeeneeteceeeeeceteeeeeaeees 367 8 3 40 Removing a Subscription reMOVeSsub ceseeceeececeeteeceseeeeneetecseeeeeeseees 369 8 3 41 Scheduling Shadow Table History Cleanup confcleanupjob 369 8 3 42 Cleaning Up Shadow Table History cleanshadowhistforpub 371 8 3 43 Cleaning Up Replication History cleanrephistoryforpub
198. e link in which case you will be directed to the registration page of the EnterpriseDB website where you can create an account Click the Next button Note For PostgreSQL only Proceed to Step 7 If you are using PostgreSQL account registration occurs later in the process Copyright 2012 EnterpriseDB Corporation All rights reserved 69 Postgres Plus xDB Replication Server with Multi Master User s Guide StackBulilder Plus 2 0 4 This download requires a registration with EnterpriseDB com Please enter your credentials below Emai Password If you do not have an account please create one now by clicking the link below Enterprise The Enterprise PostgreSQL Company Figure 30 EnterpriseDB account registration Step 7 Verify that xDB Replication Server appears in the list of selected packages Click the Next button Copyright 2012 EnterpriseDB Corporation All rights reserved 70 Postgres Plus xDB Replication Server with Multi Master User s Guide StackBuilder Pius 2 0 4 Review your selections and choose a download directory if required and then click the Next button to begin downloading the packages you have selected Selected packages Postgres Plus xDB Replication Server v9 1 56 3 Download directory Enterprise PO ES Figure 31 Selected packages An information box appears showing the download progress of the xDB Replication Server package This may take a few minutes Downloading
199. e or rename these tables and views before the subscription can be created A new subscription database can be created as shown by the following USE master GO CREATE DATABASE subdb GO Step 2 Create a SQL Server login for the subscription database user The login must have a password Copyright 2012 EnterpriseDB Corporation All rights reserved 109 Postgres Plus xDB Replication Server with Multi Master User s Guide When creating the subscription database definition the SQL Server login is entered in the Subscription Service Add Database dialog box see Section 5 3 2 CREATE LOGIN subuser WITH PASSWORD password GO Step 3 In the subscription database a database user must exist that is to be the creator and owner of the subscription tables This database user must be mapped to the SQL Server login created in Step 2 In this example the database user is given the same name as the SQL Server login subuser USE subdb GO CREATE USER subuser FOR LOGIN subuser GO Step 4 Grant the database level privileges needed by the subscription database user to create the schema and tables for the subscription GRANT CREATE SCHEMA TO subuser GRANT CREATE TABLE TO subuser GO 5 1 4 Verifying Host Accessibility If more than one computer is used to host the components of the replication system each computer must be able to communicate with the others on a
200. e path to a text file that contains the login information of either the publication server instance or the subscription server instance that you want to use The general xDB Replication Server CLI command syntax including the repsvrfile parameter is shown in the following diagram command pubname subname parameter value repsvrfile repsvrfile parameter value The xDB Replication Server CLI command to be executed is represented by command If required publication names represented by pubname or subscription names represented by subname are specified next The path to the text file containing either the publication server or subscription server login information is represented by repsvrfile The parameters and their values that are used with command are denoted by parameter and value The order on the command line in which repsvrfile repsvrfile and parameter and its values are given does not matter For example repsvrfile repsvrfilecan be given as the first parameter on the command line the last parameter on the command line or somewhere in between other parameters The following is an example of repsvrfile for a publication server host localhost port 9051 user enterprisedb Password is in encrypted form password ygJ 9AxoJEX854elcVIJPTw The following is an example of repsvrfile for a subscription server host localhost port 9052 user enterprisedb Password is in enc
201. e publication database originally resides Its network IP address is 192 168 10 102 e Node 2 is the server where the subscription database originally resides Its network IP address is 192 168 10 103 e The xDB Control database is named xdb e The publication and subscription databases have the same name e You use the publication database user for the role of the subscription database user and the subscription database user for the role of the publication database user in the switched environment e The publication server and subscription server are running on the same host node 1 Step 1 Stop all transaction processing against the publication database Step 2 Perform an on demand synchronization replication or a snapshot replication for snapshot only publications in order to replicate any pending updates in the publication database shadow tables to the subscription database Step 3 Stop the publication server and the subscription server Step 4 Review the prerequisites in Section 5 1 to ensure that the subscription database and its host can be used in the role of a publication database and the publication database and its host can be used in the role of a subscription database For practical purposes the following items are the most likely to be affected e The publication database user must be a superuser with system catalog modification privileges to allow it to act as the new subscription database user
202. e with no inheritance e lt A hash partitioned table is replicated as a single Postgres table with no inheritance Setting the importPartitionAsTable option to true allows you to replicate a broader range of Oracle partitioned table types but as normal Postgres tables without simulating partitions by using inheritance 9 3 1 5 Snapshot Replication Options Note The options described in this section apply to the publication server only unless otherwise specified The server configuration options discussed in this section apply to snapshot replications escapeTabDelimiter When JDBC Copy is used in snapshot replication the data delimiter between column values is an escaped tab character t Set this option to false if you do not want to escape the tab delimiter character escapeTabDelimiter true false The default value is true mtkCopyDelimiter Copyright 2012 EnterpriseDB Corporation All rights reserved 400 Postgres Plus xDB Replication Server with Multi Master User s Guide When JDBC copy is used in snapshot replication the data delimiter between column values is an escaped tab character t Set this option to change the data delimiter character mtkCopyDelimiter c c denotes the single replacement character for the data delimiter The default value is t enableConstBeforeDataLoad The enableConstBeforeDataLoad option controls whether or not table constraints including triggers are re enabled before l
203. e xDB Control database is accessed only by the publication server the entry permitting access from sub_ipaddr is not necessary as shown by the preceding example On the subscription server 192 168 2 8 TYPE DATABASE USER CIDR ADDRESS METHOD local is for Unix domain socket connections only Tocai EALL SLIL md5 IPv4 local connections host xdbsub enterprisedb 192 168 2 7 32 md5 host xdbsub enterprisedb 192 168 2 8 32 md5 host all all 127 0 0 1 32 md5 IPv6 local connections host all ane AANZE md5 Postgres Subscription Database For a Postgres subscription database the following entries are needed to allow access to the subscription database host sub dbname sub_dbuser pub_ipaddr 32 md5 host sub dbname sub_dbuser sub_ipaddr 32 md5 The values you substitute for sub_dbuserand sub dbname are the subscription database user name and the subscription database name you created in steps 1 and 2 of Section 5 1 3 1 For a Postgres subscription database the resulting pg_hba conf file appears as follows TYPE DATABASE USER CIDR ADDRESS METHOD local is for Unix domain socket connections only local all all md5 IPv4 local connections host xdb enterprisedb 192 168 2 7 32 md5 host subdb subuser I AGE T 32 md5 host all cules 12 050 0517 32 md5 IPv6 local connections host all all aca mle md5 Note The preceding example assumes that the publication server and the subscript
204. eDB Corporation All rights reserved 201 Postgres Plus xDB Replication Server with Multi Master User s Guide Wn Dania Pe A xDB F eplication Cc File Publication Subscripton Help S CHUY Uwe R Postgres Plus Advanced Server 1 Conflict Manager Figure 128 Opening the Synchronize dialog box Step 3 Click the Synchronize button to start synchronization replication Synchronize Publication r Publisher IP 192 168 10 102 Pustster Pon Figure 129 Synchronize dialog box Copyright 2012 EnterpriseDB Corporation All rights reserved bd Replication Servers General Realtime Monitor Replication H Le Publication Server 192 168 10 102 9051 EA SMR Sa MMR Publication schema amp Postgres Plus Advanced Server 1 Table count ty emp_pub H E edb dept H E edb emp 202 Postgres Plus xDB Replication Server with Multi Master User s Guide Step 4 Publication Synchronized Successfully appears if the synchronization was successful Click the OK button If the synchronization was not successful an error message is displayed Figure 130 Successful on demand synchronization The operations that were applied to the publication tables can be seen in the replication history See Section 7 3 for information on how to view replication history Conflicting changes that were encountered can be seen in the conflict history See Section 6 7 for information on how to vie
205. eanup Job After Every lo4 hours O Every Day at 01 jam O Every Sunday z oat 12 amy Figure 172 Cleanup Job dialog box Step 6 Click the OK button to accept the schedule 7 4 2 Cleaning Up Shadow Table History Non snapshot only publications that is publications on which synchronization replications occur whose tables experience frequent changes should have their shadow table history cleaned up periodically otherwise the amount of disk space consumed by the shadow tables in the publication database may grow too rapidly When shadow table history is cleaned up the rows in the following xDB Replication Server metadata tables are deleted e RREP_ TXSET e RREP TXSET LOG e RRST_ schema table For Oracle only When Oracle is the publication database these tables are located in the publication database in the schema of the publication database user For SQL Server only When SQL Server is the publication database these tables are located in the publication database in the schema you chose during Step 5 of Section 5 1 2 2 Copyright 2012 EnterpriseDB Corporation All rights reserved 247 Postgres Plus xDB Replication Server with Multi Master User s Guide For Postgres only When Postgres is the publication database these tables are located in the publication database in schema edb replicator pub Shadow table history cleanup can be scheduled to run periodically see Secti
206. ecified publication Synopsis cleanshadowhistforpub pubname repsvrfile pubsvrfile See Section 7 4 2 for additional information on cleaning up shadow table history Copyright 2012 EnterpriseDB Corporation All rights reserved 371 Postgres Plus xDB Replication Server with Multi Master User s Guide Parameters pubname The name of the publication for which the shadow table history is to be deleted pubsvrfile The file containing the publication server login information Examples In the following example shadow table history is deleted for publication dept emp java jar edb repcli jar cleanshadowhistforpub dept _emp gt repsvrfile pubsvrfile prop Removing shadow table s transaction history Shadow table s transaction history removed successfully 8 3 43 Cleaning Up Replication History cleanrephistoryforpub The cleanrephistoryforpub command deletes the replication history for the specified publication Synopsis cleanrephistoryforpub pubname repsvrfile pubsvrfile See Section 7 4 3 for additional information on cleaning up replication history Parameters pubname The name of the publication for which replication history is to be deleted pubsvrfile The file containing the publication server login information Examples In the following example replication history is deleted for publication dept emp java jar edb repcli jar cleanrephistoryforpub dept _emp repsvrfile pubsvrfile prop Rem
207. ee Section 7 5 3 5 for additional information on removing a filter clause Note The schema name and table or view name that you supply as values for the table parameter are case sensitive Unless quoted identifiers were used to build the database objects Oracle names must be entered using uppercase letters for example EDB DEPT and Advanced Server names must be entered in lowercase letters for example edb dept See Section 9 3 5 for additional information on quoted identifiers and case translation Parameters pubname The name of the publication containing the table or view whose filter clause is to be removed pubsvrfile The file containing the publication server login information schema t The name of the schema containing table_name This value is case sensitive table name The name of the table whose filter clause is to be removed This value is case sensitive schema_v The name of the schema containing view name This value is case sensitive view_name Copyright 2012 EnterpriseDB Corporation All rights reserved 341 Postgres Plus xDB Replication Server with Multi Master User s Guide The name of the view whose filter clause is to be removed This value is case sensitive Examples In the following example the filter clause is removed from Advanced Server table edb emp in publication analysts _ managers java jar edb repcli jar removefilterclause analysts managers gt repsvr
208. eesseesseesseessee 50 2AT Gereral Steps tsrs nettes eoit ete bens a raaa ii 50 24 27 Design Considerations ea aa cane EG Re RARS 51 2 4 3 Restrictions on Replicated Database Objects sssesseeseseeeeesrrereeresrrserseresee 53 2 4 4 Performance Considerations eseseseeseesseseeresstserssresseseresresseesresreesreseeseessee 55 2 4 5 Distributed Replication nossesseesseesseeseressstesstesseesseesseeesseeesseessesseesseesseee 58 Copyright 2012 EnterpriseDB Corporation All rights reserved 3 Postgres Plus xDB Replication Server with Multi Master User s Guide 3 Installation caivitnkeidenn ud ania keene whee 63 3 1 Installing With Stack Builder or StackBuilder Plus 000 ee eee eeeeceeeeeeeeeeeee 63 3 2 Post Installation Host Environment ceccceeesceceecceceeececeeceeceseeeceteeeeeteeeesaes 86 3 3 Registering Your xDB Replication Server Product cceeeeeeceeeeeeeeeeeeeneeeees 87 4 Introduction to the xDB Replication Console eeceeesccceecceeeeececeeeeeceeeeecsteeeenaeees 92 4 1 xDB Replication Console Tool Bart sssseesssesssesesseeessresserssessseessseessersseessee 93 Bb AD MG RG TP OSU 5 85s e renint at ae a ae e rt e esaeas a aaia aa ais 93 4 1 2 Create PUblCAtIOD nsiissninsssistiiessis siini asine ie aait 93 4 1 3 Publication Management sssicsc ts sesestqascagcey flea seated yh cmaa ia vndsules Lass MT ananeucanters 94 4 1 4 Create Subscription 0 0 essccesesresestcesssecessss neee A
209. egy Standby Conflict Resolution Strategy Earliest Timestamp Manual Update Publication Q Conflict Resolution Options updated successfully C Figure 138 Successfully updated conflict resolution options 6 9 Switching the Master Definition Node After the multi master replication system is created you can switch the role of the master definition node with another master node Step 1 Make sure the publication server whose node is the parent of the master nodes of the replication system is running and has been registered in the xDB Replication Console you are using See Section 5 2 1 for directions on starting and registering a publication server Step 2 Select the Publication Database node corresponding to the master node that you wish to set as the master definition node Copyright 2012 EnterpriseDB Corporation All rights reserved 216 Postgres Plus xDB Replication Server with Multi Master User s Guide Replication Servers Ss Publication Server 192 168 10 102 9051 192 168 10 103 5444 ier j mrnode No 1 Not available Figure 139 Selecting the master node to set as the master definition node Step 3 Click the secondary mouse button on the Publication Database node and choose Set as MDN Replication Servers SB Publication Server 192 168 10 102 9051 gt a SMR eR Postgres Plus Advanced Sener 102 B emp pi As MDN Figure 140 Sett
210. eld must be set to a password in encrypted form Using an encrypted password prevents unauthorized personnel from accessing the publication server or subscription server using the values of user and password if the file was somehow compromised The encrypted password cannot be used to access the publication server or subscription server from its dialog box in the xDB Replication Console See Section 8 3 4 for directions on generating an encrypted password using the encrypt command 8 2 5 Running xDB Replication Server CLI Using a Parameter File The paramfile command allows you to run an xDB Replication Server CLI command and its parameters that have been coded into a text file This technique is useful if you want to save the command and its parameters for repeated executions Copyright 2012 EnterpriseDB Corporation All rights reserved 317 Postgres Plus xDB Replication Server with Multi Master User s Guide The syntax for executing paramfile is shown by the following java jar XDB HOME bin edb repcli jar paramfile cmdparamfile The syntax of the xDB Replication Server CLI command and its parameters coded into text file cndparamfile is the same as if given at the command line prompt as shown by the following command pubname subname parameter value repsvrfile repsvrfile parameter value Using the paramfile command has the following restrictions e Only one xDB Replication S
211. ement is then used to drop the metadata schema edb replicator pub db Ne db nterprisedb You are now connected to database edb as user enterprisedb edb DROP SCHEMA edb replicator pub CASCAD NOTICE drop cascades to 16 other objects DETAIL Ghuopmedscadess toOmsequence ss drop cascades to sequenc drop cascades to sequenc dopmcais codes eOmtealolemmcclnc pile at oreo drop cascades Eo cable edbprepilnicatom pub dopmcads codes Eom table mech nmepil cater gpl ciopmcasicadesmECmeabliommecdiopne pill caer seule ekoo Cascades To table eclo raplicator pugs dropieoaccadesito table edb enepilic ator gpl drop cascades Eo table edb replicator pub cwopmCascades To table eclo raplicator puos cdkop cCascecdees TO table eclo replicator pig dvopwcascades eo eabile edb i repikneatoripUbR drop cascades to schema rrep pkg dwopmcasicades tO taole eclo replicar pigs ekoo Cascades To table eco replicator pugs DROP SCHEMA Bue S dipcepilhic aivor pub r repiconmoniseg Redbpaepiieacommoubr ssc pease Co Golo replicator PUD nec CSEE SSC rrep_ tables rrep publication tables Errepi Sie rrep_mmr_txset rrep publication subscriptions ieicisjo iessieic lev ievet j9 _IKOels rrep_mmr pub group TEePIPLOPEE HIES piep eseat ngalhtii reoCredbFIepE reS tCedbIenme Step 5 Repeat steps 3 and 4 for each publication database definition subordinate to the publication server If all of the me
212. epsvrfile subsvrfile Parameters subsvrfile The file containing the subscription server login information Examples The following example lists the subscription database IDs of the subscription database definitions java Jar edb repeli Jar printsubdbids repsvrfile subsvrfile prop Printing subscription database ids 1 2 8 3 28 Printing Subscription Database Details printsubdbidsdetails For SMR only The printsubdbidsdetails command prints the connection information for each subscription database definition Synopsis printsubdbidsdetails repsvrfile subsvrfile The output has the following components Copyright 2012 EnterpriseDB Corporation All rights reserved 351 Postgres Plus xDB Replication Server with Multi Master User s Guide dbid host port dbname user Note The database user s password is not displayed Parameters subsvrfile The file containing the subscription server login information dbid The subscription database ID assigned to the subscription database definition host The IP address of the host on which the subscription database server is running port The port number on which the database server is listening for connections dbname The Postgres or SQL Server database name the Oracle SID or the Oracle service name of the subscription database user The subscription database user name Examples The following are the subscription database definitions subordinate to the su
213. er Clause deptno 30 E E Subscription Server 192 168 2 7 9052 Figure 207 Selected table s filter clause displayed in the information window Alternate Step 2 Click the secondary mouse button on the Table node of the table whose filter clause you want to view and choose View Filter Clause The Table Filter Clause window appears Click the Close button when you have finished viewing Copyright 2012 EnterpriseDB Corporation All rights reserved 281 Postgres Plus xDB Replication Server with Multi Master User s Guide r Table DEPT Filter Clause deptno 30 Figure 208 Table Filter Clause window 7 5 3 4 Updating the Filter Clause For SMR only A filter clause on a publication table can be added or modified Step 1 Make sure the publication server whose node is the parent of the publication you wish to change is running and has been registered in the xDB Replication Console you are using See Section 5 2 1 for directions on starting and registering a publication server Step 2 Click the secondary mouse button on the Table node of the table whose filter clause you want to update and choose Update Filter Clause The Table Filter Clause window appears Step 3 Enter the text of a SQL WHERE clause to select the rows you want to replicate Omit the WHERE keyword Click the Validate button Copyright 2012 EnterpriseDB Corporation All rights reserved 282 Postgres Plus xDB Replication Server wit
214. er a broad range of supported use cases Some of the more popular uses of single master replication include the following 2 1 1 Offloading Reporting and Business Intelligence Queries In this use case users take all or just a subset of data from a production OLTP system and replicate it to another database whose sole purpose is to support reporting queries This can have multiple benefits a reporting loads are removed from the OLTP system improving transaction processing performance b query performance improves as well without being subordinated to transactions on the system and c in Oracle installations the reporting server duties can be handled by a product like Postgres Plus Advanced Server reducing licensing costs for a reporting server 2 1 2 Using Warm Standby Servers When many organizations wish to improve the availability of their data a cost effective solution is often the use of warm standby servers These are database servers kept up to date with the online system through replication that can be brought online quickly in the event of a failure in the production system Warm standby servers can also be used for regular maintenance by gracefully switching over to the standby server so that the production server can be brought offline for regular maintenance 2 1 3 Testing Systems in Parallel Often times upgrading or moving to a new database system requires that the old and new systems be up and running in parallel to allow for
215. er and has the privilege to modify pg_ catalog tables See Section 5 1 3 Step 7 For Linux only Verify that the network IP address returned by the sbin ifconfig command either matches the IP address associated with the host name in the etc hosts file see Section 5 1 4 2 or matches the IP address specified with the java rmi server hostname configuration option in the publication and subscription server configuration files see Section 9 3 1 6 9 2 4 Troubleshooting Areas The following topics provide information on specific problem areas you may encounter 9 2 4 1 Starting the Publication Server or Subscription Server Note The subscription server only applies to single master replication systems Copyright 2012 EnterpriseDB Corporation All rights reserved 384 Postgres Plus xDB Replication Server with Multi Master User s Guide If you cannot start the publication server or the subscription server perform the following steps Step 1 Check the pubserver log and subserver 1og files for errors Step 2 Check the log file of the Postgres database server running the xDB Control database for errors Step 3 Verify that the user name and password in the xDB Replication Configuration file on the hosts running the publication server and subscription server match a superuser name and password in the Postgres database server running the xDB Control database that the publication server and subscription server are attempting to access
216. er contains tables from two schemas that are replicated to a database residing in either PostgreSQL or Postgres Plus Advanced Server L Server to Postgres replication system xDB Replication Console or Figure 13 SQL Server to PostgreSQL or Advanced Server replication The following describes the logical components in the preceding diagram Copyright 2012 EnterpriseDB Corporation All rights reserved 40 Postgres Plus xDB Replication Server with Multi Master User s Guide e The publication server to be used is identified by registering its network location user name and password e A publication database definition is created subordinate to the SMR type node under the publication server The SQL Server login pubuser is specified in the definition along with the database network location and database identifier The schema pubuser was created during the publication database preparation step as described in Section 5 1 2 2 It is populated with database objects for the replication system s metadata when you create the publication database definition e A publication named pub is created subordinate to the publication database definition The publication consists of table A in schema S1 and tables B and C in schema S2 e The subscription server to be used is identified by registering its network location user name and password e A subscription database definition is created subordinate to the subscription server The Postgres
217. er has CR DATABASE privilege on the publication database or the database user is a superuser Publication cannot be created One or more tables have no attributes defined and cannot be published Unselect the specific tables and retry Resolution In Postgres it is possible to create a table with no columns A publication is not allowed to include a Postgres table with no columns since the corresponding subscription table cannot be created in Publication publication_name already exists on choose a different name and then proceed Resolution Publication names must be unique within a publication server Enter a different publication Copyright 2012 EnterpriseDB Corporation All rights reserved 377 Postgres Plus xDB Replication Server with Multi Master User s Guide Error Messages and Resolutions Publication cannot be created Table table_name does not contain a primary key Transactional replication is not supported for a non pk table Resolution All tables used for synchronization replication must have primary keys Create a primary key on the table or add the table to a snapshot only publication Publication cannot be created The publication creation process timed out as one or more tables may be locked by another session Please retry later Resolution Fora Postgres publication that is not for snapshot only the publication database user must be able to create triggers on the publication tables In order t
218. erver CLI command can be coded into the parameter file cmdparamfile e The parameters to be used with the xDB Replication Server CLI command must all be included in cmdparamfile You cannot code some of the parameters into cmdparamfile and give other parameters on the command line The following example creates an Advanced Server publication database definition using a parameter file named addpubdb advsvr The following is the content of parameter file addpubdb_ advsvr addpubdb repsvrfile home user pubsvrfile prop dbtype enterprisedb Cloinosic 192 Weds 2 4 dbport 5444 dbuser pubuser dbpassword ygJ9AxoJEX854elcVIJPTw database edb Kepoqrouptype s Note Unlike entering the xDB Replication Server CLI command and its parameters directly at the command line prompt when coded into a text file no continuation characters are needed to continue onto the following lines The following shows the execution of the paramfile command java jar edb repcli jar paramfile addpubdb advsvr Adding Publication Database Publication database added successfully Publication Database id 1 Copyright 2012 EnterpriseDB Corporation All rights reserved 318 Postgres Plus xDB Replication Server with Multi Master User s Guide 8 3 xDB Replication Server CLI Commands This section provides a description syntax diagram and examples of each xDB Replication Server CLI command Commands are presented in the order in which they will
219. erver configuration files respectively See Section 9 3 1 for a detailed explanation of how to set the configuration options in these files Note Most of these configuration options are applicable to multi master replication systems as well Options applicable to multi master replication systems are those that apply to the publication server and are not specific to a database product other than Postgres such as an Oracle feature 5 8 1 Optimizing Snapshot Replication This section discusses configuration options for improving snapshot replication performance Note The options described in this section apply to the publication server only and are set in the publication server configuration file unless otherwise specified copy ViaDBLinkOra When the copyViaDBLinkOra option is set to true the Oracle database link API dblink_ ora is used instead of JDBC Copy to populate the Postgres subscription tables from an Oracle publication during snapshot replication Oracle database link provides an additional performance improvement over JDBC COPY copyViaDBLinkOra true false Copyright 2012 EnterpriseDB Corporation All rights reserved 167 Postgres Plus xDB Replication Server with Multi Master User s Guide The default value is false useFastCopy Set the useFastCopy option to true to skip Write Ahead Log WAL logging during COPY operations in order to optimize data transfer speed The archive mode configuration par
220. esday the result is Wednesday the 1 If the 1 is a Sunday the result is Monday the 2 If the 1 is a Saturday the result is Monday the 3 because the result does not go into the previous or following month 2 3 The third Monday of the month 2 Monday 3 third occurrence The following illustrates some examples of cron expressions Table 11 Cron Expression Examples Ooz zo awe gt 2009 fI20000 noon on August 20 2009 pS 15 2 AUG wen 11500 PM every Wednesday in Augus 8 30 30 AM every Monday Wednesday and Friday of every month o o 8 2 2 6 8 00 00 AM Monday thru Friday of every month 30 30 8 MON WED FRI 8 00 00 AM 8 30 00 AM 9 00 00 AM 9 30 00 AM 0 0 30 8 9 10 15 L 10 00 00 AM 10 30 00 AM on the 15 and the last day of the month of every month 9 00 00 AM each Saturday in September 1 00 00 AM on the last Monday of the month of every month 0 30 16 15W sep 30 00 PM on the weekday of September closest to the 15 Copyright 2012 EnterpriseDB Corporation All rights reserved 405 Postgres Plus xDB Replication Server with Multi Master User s Guide 0 30 16 WED 2 M3000 PM on the second Wednesday of every month 9 3 4 Disabling Foreign Key Constraints for Snapshot Replications In a snapshot replication the publication server calls EnterpriseDB s Migration Toolkit which disables foreign key constraints on tables so it can truncate the target tables before loading
221. esh icon you will see the schedule properties in the General tab File Publication Subscription Help S Usiwy Vea tel ta Replication Servers General amp e Publication Server 192 168 2 7 9051 amp A Subscription Server 192 168 2 7 9052 Property Value Ej R Postgres Plus Advanced Server 192 1 Publication server 192 168 2 7 eg Publication server port 9051 amp sales_dept Job type Synchronize E E EDB DEPT Scheduled time 2012 06 07 10 26 54 EDB EMP Previous fire time Not available Next fire time 2012 06 08 01 00 00 Cron expression 001 MON WED FRI SUN Figure 150 Information window with the replication schedule Copyright 2012 EnterpriseDB Corporation All rights reserved 227 Postgres Plus xDB Replication Server with Multi Master User s Guide 7 2 Managing a Schedule Once a schedule has been created xDB Replication Server performs replications according to the schedule until the schedule is updated or removed The updating or removal of a schedule has no effect on a replication that has already been started If a replication is in progress when the schedule is updated or removed the in progress replication continues until completion 7 2 1 Updating a Schedule The following steps illustrate how to change an existing schedule Step 1 For SMR only Make sure the subscription server whose node is the parent of the subscription you wish to change is running and has been registered in t
222. et of inherited tables is created in Postgres to which the Oracle partitioned table is replicated The rows can be stored in different physical locations e A plain single table with no inheritance is created in Postgres to which the Oracle partitioned table is replicated All rows are stored in one physical location e No table is created in Postgres for the Oracle partitioned table and an error message is written to the Migration Toolkit log file Copyright 2012 EnterpriseDB Corporation All rights reserved 399 Postgres Plus xDB Replication Server with Multi Master User s Guide When importPartitionAsTable false the default setting the following occurs e A list partitioned table is replicated as a set of inherited Postgres tables e A range partitioned table is replicated as a set of inherited Postgres tables e lt A hash partitioned table is not replicated to Postgres and an error message is written to the Migration Toolkit log file Note If there are subscription tables created as sets of Postgres inherited tables then you must also set the enableConstBeforeDataLoad option in the publication server configuration file to true See Section 9 3 1 5 for information on the enableConstBeforeDataLoad option When importPartitionAsTable true the following occurs e A list partitioned table is replicated as a single Postgres table with no inheritance e A range partitioned table is replicated as a single Postgres tabl
223. ew host perform the following step otherwise go to Step 11 The following example assumes you decide to use the publication server and subscription server running on node 2 Update the subscription metadata to the new location of the publication server managing its associated publication UP DARE CCl mere oliie aie Ors Mb nee Dass Cig edtOnsins Sta UNS e taieta mem TUG 5 AGS oAO LOS p Update the publication metadata to the new location of the subscription server managing its associated subscription UPN eclo replicator Dip Gre Sill Serwers SAL Sil sewer jo WL oso IO 5 LOS g Verify that the xDB Replication Configuration files on the publication server and subscription server contain the correct information in accordance with Step 6 Step 11 The controlled switchover is now complete Start the publication server and the subscription server 5 7 Performing Failover Failover is the replacement of the publication database by the subscription database should a failure occur on the publication database or its host Failover is considered an irreversible action so the subscription database permanently takes over the role of the publication database Generally the same steps must be followed to perform a failover as was discussed for a controlled switchover in Section 5 6 however the following points must also be taken into consideration e Ifthe xDB Control database was running on the node where the failure occurre
224. explicit named subscription in a multi master replication system In a single master replication system replication is said to occur when xDB Replication Server initiates and completes either of the following processes 1 applies changes that have been made to rows in the publication since the last replication occurred to rows in tables of the subscription database called synchronization or 2 copies rows of the publication to empty tables of the subscription database called a snapshot See Section 2 2 6 for further discussion on snapshots and synchronization The subscription tables are the tables in the subscription database created from corresponding tables or views in the publication Note In a single master replication system xDB Replication Server creates a table in the subscription database for each view contained in the publication In a multi master replication system the concept and definition of replication is nearly identical to a single master replication system with the following modifications 1 synchronization can occur between any pair of databases referred to as master nodes participating in the replication system and 2 a snapshot can occur from the publication database a master node designated as the master definition node to any of the other master nodes The following diagrams illustrate some basic single master replication system examples Copyright 2012 EnterpriseDB Corporation All rights reserved 16
225. fied by registering its network location user name and password e A subscription database definition is created subordinate to the subscription server The SQL Server login subuser is specified in the definition along with the database network location and database identifier e A subscription named sub is created subordinate to the subscription database definition When the subscription is created the subscription server creates schemas named S1 and S2 in the subscription database The table definitions for tables A B and C are also created at this time When replication occurs the publication server populates these tables with rows from the publication The following screen capture shows how the logical components of this replication system appear in the xDB Replication Console replication tree Copyright 2012 EnterpriseDB Corporation All rights reserved 46 Postgres Plus xDB Replication Server with Multi Master User s Guide Deri xDB Replication C S Publication Server 192 168 2 7 9051 Bd sur 5 p PostgreSQL 192 168 2 7 5432 pubdb pubuser H pub FE s1 a E s2 b FE s2 c Fa MMR amp Subscription Server 192 168 2 7 9052 H E s1 a FE s2 b H E s2 c Figure 18 Postgres to SQL Server replication tree See Chapter 4 for an introduction to the xDB Replication Console 2 3 3 5 Postgres Multi Master Replication The following is an illustration of a basic Postgres multi master replication sys
226. file pubsvrfile prop gt table edb emp Removing table filter clause Filter clause has been removed successfully 8 3 19 Printing the Conflict Resolution Strategy printconfresolutionstrategy For MMR only The printconfresolutionstrategy command prints the conflict resolution strategy and the standby conflict resolution strategy of the specified table Synopsis e printconfresolutionstrategy pubname repsvrfile pubsvrfile table schema t table_ name See Section 6 6 for additional information on conflict resolution Note The schema name and table or view name that you supply as values for the table parameter are case sensitive Unless quoted identifiers were used to build the database objects Oracle names must be entered using uppercase letters for example EDB DEPT and Advanced Server names must be entered in lowercase letters for example edb dept See Section 9 3 5 for additional information on quoted identifiers and case translation Parameters pubname The name of the publication containing the table whose conflict resolution strategy is to be printed pubsvrfile The file containing the publication server login information schema t Copyright 2012 EnterpriseDB Corporation All rights reserved 342 Postgres Plus xDB Replication Server with Multi Master User s Guide The name of the schema containing table_name This value is case sensitive table name The
227. fining the master node as described in Section 6 3 or by using an on demand snapshot as described in Section 6 5 1 while other master nodes can be loaded from an offline snapshot Copyright 2012 EnterpriseDB Corporation All rights reserved 311 Postgres Plus xDB Replication Server with Multi Master User s Guide The following steps describe how to create a master node from an offline snapshot Step 1 Register the publication server add the master definition node and create the publication as described in Section 6 2 Note The following steps must be performed before adding a master node that is to be loaded by an offline snapshot Steps 2 through 10 can be repeated each time you wish to create an additional master node from an offline snapshot Step 2 If you are adding a master node to an active replication system with an enabled schedule remove the schedule for the duration of the following steps See Section 7 2 2 for directions on removing a schedule Step 3 Modify the publication server configuration file if these options are not already set as described by the following e Change the of flineSnapshot option to true When the publication server is restarted of flineSnapshot set to true has the effect that adding a master node sets a column in the xDB Control database indicating an offline snapshot is used to load this master node e Set the batchInitialSync option to the appropriate setting for your particular situation as
228. formation Host 192 168 2 6 Port a ae seit 9x0 Canesten Figure 67 Publication Service Add Database dialog box Step 4 Click the Test button If Test Result Success appears click the OK button then click the Save button Publication Service Add Database Figure 68 Successful publication database test Copyright 2012 EnterpriseDB Corporation All rights reserved 122 Postgres Plus xDB Replication Server with Multi Master User s Guide If an error message appears investigate the cause of the error correct the problem and repeat steps 1 through 4 When the publication database definition is successfully saved a Publication Database node is added to the replication tree under the Publication Server node File Publication Subscription Help CHUY Bees ie ta Replication Servers General Publication Server 192 168 2 7 9051 E SMR Property g Oracle 192 168 2 6 1521 xe pubuser Host 192 168 2 6 a MMR Port 1521 SID xe User pubuser Figure 69 Replication tree after adding a publication database For Oracle only Multiple Oracle databases can be added as publication databases by completing the Add Database dialog box for each database It is also permissible to add the same Oracle database as two or more distinct publication database definitions if you use different publication database user names for each publication database definition For Postgres or SQL
229. ful across all databases Click the OK button Figure 229 DDL replicated successfully If DDL replication was not successful the problem must be investigated and resolved on a case by case basis Factors to look for include the following e Were the modifications in the ALTER TABLE statements successfully applied to the target table in each database of the replication system Copyright 2012 EnterpriseDB Corporation All rights reserved 306 Postgres Plus xDB Replication Server with Multi Master User s Guide e Were the replication triggers on the target table modified to account for the ALTER TABLE statements e Was the shadow table RRST_schema_tab1e located in the _edb replicator pub schema in each database of the replication system modified to account for the ALTER TABLE statements If it is apparent that the replication system is not in a consistent state regarding the table definitions see the beginning of Section 7 5 4 for guidance on how to deal with such issues 7 7 Loading Tables From an External Data Source Offline Snapshot There may be circumstances when you want to initially load your target tables subscription tables of a single master replication system or master nodes other than the master definition node of a multi master replication system using a method other than the snapshot replication functionality of xDB Replication Server This is referred to as using an offline snapshot
230. g pgdbschedule true false The default value is false 9 3 1 8 Forcing Immediate Shadow Table Cleanup Note The option described in this section applies to the publication server only A cleanup job is provided that can be run on demand or on a schedule to remove dead processed tuples from the shadow tables see Section 7 4 Copyright 2012 EnterpriseDB Corporation All rights reserved 402 Postgres Plus xDB Replication Server with Multi Master User s Guide However to perform even quicker cleanup scheduling turn on this option to force the cleanup of shadow tables after every synchronization replication postSyncShadowTableCleanup tru false The default value is false 9 3 1 9 DDL Change Replication Table Locking Note The option described in this section applies to the publication server only When the DDL change replication process is invoked each affected table in the replication system is acquired in turn with an exclusive lock before the DDL change is applied to the table Set ddlChangeTableLock to false if you do not want an exclusive lock placed on the table before applying the DDL change This option should be set to false only if there are no write transactions expected on the target table If write transactions do occur they may not be recorded by the replication system See Section 7 6 for information on DDL change replication ddlChangeTableLock tru false The default value is true 9
231. g a total 2868 rw r r 1 root daemon 554871 Nov 2 07 23 edb jdbcl4 jar Sayre e i rook Cacnea 2856038 Now 2 O7 23 Jece l Zau a eoe i ROSIE BOOGIE ISOOSLG Wow V 20321 ocios tei Iene we e oot daenon SO Nor MON oo pos toresa Orta 0erm Gio Co aE Note If you installed xDB Replication Server to a location other than the Postgres installation directory copy the ojdbc14 jar file to the 1ib jdbc subdirectory of the location where you installed xDB Replication Server Step 3 If the subscription server is running on a different host than the publication server repeat steps 1 and 2 for the subscription server host 5 1 1 2 Enabling Access to SQL Server Note The directions in this section apply only if SQL Server will be used as the publication or subscription database Step 1 Be sure SQL Server Authentication mode is enabled on your SQL Server database engine SQL Server Authentication mode allows the use of SQL Server logins such as the built in system administrator login sa Using the default settings for SQL Server installation only Windows Authentication mode is enabled which utilizes the accounts of the Windows operating system for authentication In order to permit SQL Server Authentication mode you must change the authentication mode to Mixed Mode Authentication which permits both Windows Authentication and SQL Server Authentication This can be done using SQL Server Management Studio Refer to the appropriate S
232. gers Tables removed successfully 8 3 16 Printing a Filter Clause printfilterclause For SMR only The printfilterclause command prints the filter clause of the specified table or view Synopsis printfilterclause pubname repsvrfile pubsvrfile table schema_t table_name schema_v view_name See Section 7 5 3 3 for additional information on viewing a filter clause Note The schema name and table or view name that you supply as values for the table parameter are case sensitive Unless quoted identifiers were used to build the database objects Oracle names must be entered using uppercase letters for example EDB DEPT and Advanced Server names must be entered in lowercase letters for example edb dept See Section 9 3 5 for additional information on quoted identifiers and case translation Parameters pubname The name of the publication containing the table or view whose filter clause is to be printed pubsvrfile The file containing the publication server login information Copyright 2012 EnterpriseDB Corporation All rights reserved 338 Postgres Plus xDB Replication Server with Multi Master User s Guide schema t The name of the schema containing table_name This value is case sensitive table name The name of the table whose filter clause is to be printed This value is case sensitive schema_v The name of the schema containing view name This value is case sensitive
233. gin please select the installation you are installing software for from the list below Your computer must be connected to the Internet before proceeding Postgres Plus Advanced Server 9 1 on port 5444 x 1 update is available Enterprise The Enterprise Postare SOL Company Proxy servers Figure 26 StackBuilder Plus welcome screen Step 5 For Advanced Server Expand the Replication Solutions node and check the box for xDB Replication Server Click the Next button Copyright 2012 EnterpriseDB Corporation All rights reserved 66 Postgres Plus xDB Replication Server with Multi Master User s Guide StackBuilder Plus 2 0 4 Please select the applications you would like to install Vv i Categories Add ons tools and utilities Database Drivers Database Server EnterpriseDB Solution Pack Replication Solutions ae Postgres Plus xDB Replication Server v9 1 56 3 I Slony Replication v2 1 0 3 Spatial Extensions W Web Applications R Postgres Plus xDB Replication Server is an E Enterprise asynchronous master to slave replication The Enterprise PosigreSOL Company system i Figure 27 StackBuilder Plus applications Step 5 For PostgreSQL Expand the Registration Required and Trial Products node and then expand the Solution Pack node Check the box for xDB Replication Server under the Solution Pack list and click the Next button Copyright 2012 EnterpriseDB Corporation All rights reserved 67 Pos
234. gistered as the publication database Resolution Occurs when adding a publication database Publications cannot be created in the xDB Control database so you cannot register the xDB Control database as a publication database The replication process could not be completed due to a database failure Check the database state and retry Resolution May be caused by characters in the publication data that are illegal for the character set of the subscription database Check the snapshot replication failure log file or the database server log file See Section 9 3 1 2 Replication server does not support Oracle to Oracle replication Resolution See Section 9 1 for supported database server configurations Use Oracle products for Oracle to Oracle replication Subscription subscription name already exists on the subscriber server Pleas choose a different name and then proceed Resolution Subscription names must be unique within a subscription server Enter a different subscription name Copyright 2012 EnterpriseDB Corporation All rights reserved 378 Postgres Plus xDB Replication Server with Multi Master User s Guide Error Messages and Resolutions Subscription subscription name cannot be removed Reason Publication does not exist on the publication server Resolution Warning issued if the subscription you are attempting to remove does not have an associated publication You can still remove the subscription Subs
235. gle master replication system See sections 6 2 2 and 6 3 for a multi master replication system Copyright 2012 EnterpriseDB Corporation All rights reserved 262 Postgres Plus xDB Replication Server with Multi Master User s Guide The steps described in this section show you how to update the publication database login information stored in the xDB Control database should any of these attributes of the actual physical database change Note Depending upon the database type Oracle SQL Server or Postgres certain attributes must not be changed You must not change any attribute that alters access to the schema where the metadata database objects were created when you originally added this publication database definition See Section 5 2 4 for the location of the metadata database objects Attributes you must not change include the following e The Oracle login user name of an Oracle publication database as the metadata already resides in this Oracle user s schema e The database server network location if the new network location references a database server that does not access the publication database where the metadata database objects are stored e The database identifier if the new database identifier references a different physical database than where the metadata database objects are stored Attributes you may change include the following e The login user name s password to match a changed database user password e The da
236. gres database clusters 2 3 1 10 Master Definition Node The first node added to create a multi master replication system is initially designated the master definition node This node must contain the table definitions and optionally the initial set of rows that are to be included in the publication Copyright 2012 EnterpriseDB Corporation All rights reserved 32 Postgres Plus xDB Replication Server with Multi Master User s Guide As subsequent databases are added as master nodes to the replication system the table definitions and initial row sets can optionally be propagated from the master definition node to the newly added master nodes After the multi master replication system is defined it is possible to reassign the role of the master definition node to another master node in the multi master replication system The significance of this reassignment is that snapshots can be taken from the newly appointed master definition node to other master nodes This could be beneficial if the data in the old master definition node becomes corrupt or out of sync with the other master nodes and needs to be completely refreshed by a snapshot from another master node 2 3 2 Logical Components This section discusses the logical components of a replication system how they are related to each other and how they correspond to the programs and databases in a replication system The logical components are created when you build a replication s
237. gure 167 Table replication history tab Step 3 Click the View Data link to show a list of each change made to the table during the synchronization replication The Synchronize History window shows two update operations followed by one insert operation against the emp target table that correspond to the following set of SQL statements executed on the emp source table UPDATE emp SET hiredate TO DATE 07 JUN 12 mgr 7698 WHERE empno IN QOOL OWZ E INSERT INTO emp empno ename job mgr deptno VALUES 9003 JOHNSON SALESMAN 7698 30 Copyright 2012 EnterpriseDB Corporation All rights reserved 241 Postgres Plus xDB Replication Server with Multi Master User s Guide Table EDB EMP TX Count 3 Start Time 2012 06 07 11 49 04 TX Type Displaying rows 1 3 of 3 Row Inserted U Row Updated D Row Deleted TX Type EMPNO ENAME JOB MGR HIREDATE SAL 2001 JONES 7698 2012 06 07 00 0 9002 SMITH _ 7698 2012 06 07 00 0 2003 JOHNSON SALESMAN 7698 Figure 168 Synchronize History window Note Since all insert update and delete operations on all source tables are recorded in shadow tables the size of the shadow tables may grow considerably over time for volatile source tables The rows shown in the Synchronize History window are obtained from these shadow tables Rows in the shadow tables can be periodically deleted See Sect
238. h Multi Master User s Guide deptno IN 20 30 Figure 209 Validating a filter clause Step 4 If Validation Result Passed appears click the OK button If Validation Result Passed does not appear investigate the error and make the necessary corrections Copyright 2012 EnterpriseDB Corporation All rights reserved 283 Postgres Plus xDB Replication Server with Multi Master User s Guide sure 210 Successful validation of filter clause Step 5 Click the Update ern and then click OK in response to Filter Clause Has Been Updated Successfully Copyright 2012 EnterpriseDB Corporation All rights reserved 284 Postgres Plus xDB Replication Server with Multi Master User s Guide igure 211 Successful update of filter clause Step 6 Close the Table Filter Clause dialog box The updated filter clause appears in the General tab of the information window Copyright 2012 EnterpriseDB Corporation All rights reserved 285 Postgres Plus xDB Replication Server with Multi Master User s Guide ig Replication Servers General Replication History g 5i D Publication Server 192 168 2 7 9051 Ba sur Property E u Oracle 192 168 2 6 1521 xe pubus Name DEPT S sales_dept Schema EDB PK attributes DEPTNO Ei EDB EMP Attributes count 3 fa MMR Filter Clause deptno IN 20 30 E Subscription Server 192 168 2 7 9052 Figure 212 Updated filter clause 7 5 3 5 Removing a Filter C
239. h other by a network In a multi master replication system the publication database is also referred to as the master definition node A database plays the roles of both a publication database and a subscription database if it contains publications and subscriptions 2 3 1 8 Subscription Database Note The subscription database applies only to single master replication systems The subscription database contains the tables created from a subscription The subscription database may be running on the same host or on a different host than where the subscription server is running as long as the hosts are accessible to each other by a network A subscription database can also serve as a publication source for replicating to a third server if desired This configuration is referred to as cascading replication A database plays the roles of both a publication database and a subscription database if it contains publications and subscriptions such as in the cascaded replication scenario 2 3 1 9 Master Node In a multi master replication system the databases containing the set of tables the publication for which row changes are to be replicated are called master nodes The master nodes may be running on the same host or on different hosts than where the publication server is running as long as the hosts are accessible to each other by a network The master nodes may be running under the same or under multiple database server instances Post
240. h the subscription server will run Default port number is 9052 Click the Next button Copyright 2012 EnterpriseDB Corporation All rights reserved 80 Postgres Plus xDB Replication Server with Multi Master User s Guide Subscription Server Details Please specify a port on which subscription server will run Port 9052 BitRock Installer Figure 43 Subscription server details Step 18 For the operating system account under which the publication server or subscription server is to run enter postgres enterprisedb if you are using Advanced Server installed in Oracle compatible configuration mode Copyright 2012 EnterpriseDB Corporation All rights reserved 81 Postgres Plus xDB Replication Server with Multi Master User s Guide Publication Subscription Service Account Please provide the user name of the account under which the publication subscription service will run Operating system username enterprisedb BitRock Installer lt Back Next gt Cancel Figure 44 Publication subscription server operating system account Step 19 On the Ready to Install screen click the Next button Copyright 2012 EnterpriseDB Corporation All rights reserved 82 Postgres Plus xDB Replication Server with Multi Master User s Guide Ready to Install Ra Setup is now ready to begin installing xDB Replication Server on your computer BitRock Installer Figure 45 Ready to install An information
241. hat table its triggers and shadow table If there is a backlog of pending transactions it is recommended to perform an explicit synchronization replication before performing DDL change replication to avoid prolonging the DDL change replication process for a longer period of time DDL change replication should be performed when the OLTP rate is very low near zero Note Exclusive acquisition of each target table during the DDL change replication process can be turned off by setting ddlChangeTableLock to false However this should be done only when there are no write transactions taking place against the target table otherwise transactions may not be recorded by the replication system See Section 9 3 1 9 for addition information on the dd1ChangeTableLock configuration option The following is the series of steps that occur during the DDL change replication process e The publication server performs a health check across all databases in the replication system to ensure they can be accessed If any database is not available the DDL change replication process is aborted with a notification to the user e Ifthe publication server configuration option ddlChangeTableLock is set to its default value of true an exclusive table lock is requested on the table to which the DDL change is to be applied If another application already has a lock on the table there is a wait time of 2 minutes after which the DDL change replication process is aborted if
242. have 3 An increment greater than or equal to the number of nodes guarantees unique IDs as shown in Table 5 e Common sequence All nodes share a common sequence object however this has the major disadvantage of slowing down transaction processing due to network round trips associated with each ID generation A Table 5 Sequence With Start Value Variation Sequence Clause Master Node A Master Node B Master Node C INCREMENT BY Generated IDs 6 6 5 Example Conflict Resolution This example illustrates a scenario where a transaction change originating from the first master node is successfully applied to the second master node but conflicts with the third master node The conflict resolution option is set to latest timestamp Table 6 Conflict Resolution Example Timestamp Master Node A Master Node B Master Node C 0 id 2 address jid 2 address Jid 2 address ADDR ADDR t1 Node A UPDATE id 2 address id 2 address jid 2 address addrbook SET ADDR A ADDR ADDR Copyright 2012 EnterpriseDB Corporation All rights reserved 208 Postgres Plus xDB Replication Server with Multi Master User s Guide Timestamp Master Node A Master Node B Master Node C r ee FE id 2 address id 2 address id 2 address ADDR A ADDR ADDR C Synchronization pushes Node A changes to id 2 address id 2
243. he SQL Server publication schema name is dbo the subscription tables are created under a schema named dbo _sq1 in Postgres e For SQL Server only There must be no existing tables or views with the same schema qualified name as a table or view in a publication that will be replicated to this database For example if the publication contains a table with the schema qualified name edb dept then the SQL Server subscription database must not have an existing table or view with the schema qualified name edb dept at the time you create the subscription Note If the Postgres publication schema name is public the subscription tables are created under a schema named public sql in SQL Server Note A database that has been added as a publication database can also be used as a subscription database Step 1 Make sure the database server in which the subscription database resides is running and accepting client connections Step 2 Select the Subscription Server node From the Subscription menu choose Subscription Database and then choose Add Database Alternatively click the secondary mouse button on the Subscription Server node and choose Add Database The Subscription Service Add Database dialog box appears Copyright 2012 EnterpriseDB Corporation All rights reserved 134 Postgres Plus xDB Replication Server with Multi Master User s Guide Step 3 Fill in the following fields e Database Type Select Oracle SQL Server PostgreSQL
244. he replication history See Section 7 3 for information on how to view replication history 5 4 2 Performing Synchronization Replication After the first snapshot replication subsequent replications can be performed using synchronization replication if the publication was not created as a snapshot only publication Step 1 Select the Subscription node of the subscription for which you wish to perform synchronization replication Copyright 2012 EnterpriseDB Corporation All rights reserved 145 Postgres Plus xDB Replication Server with Multi Master User s Guide td Replication Servers H E Publication Server 192 168 2 7 9051 Subscription Server 192 168 2 7 9052 o Postgres Plus Advanced Server 192 Publication server E a Publication server port sales_dept Scheduled job status H E EDB DEPT H E EDB EMP Figure 90 Selecting a subscription for an on demand synchronization Step 2 Open the Synchronize dialog box in any of the following ways e From the Subscription menu choose Synchronize e Click the secondary mouse button on the Subscription node and choose Synchronize e Click the primary mouse button on the Synchronize icon GE Publicatio S E Subscript P Postg Publication server Publication server port Scheduled job status Figure 91 Opening the Synchronize dialog box Copyright 2012 EnterpriseDB Corporation All rights reserved 146 Postgres Plus xDB Replic
245. he xDB Replication Console you are using See Section 5 3 1 for directions on starting and registering a subscription server Step 1 For MMR only Make sure the publication server whose node is the parent of the master definition node you wish to change is running and has been registered in the xDB Replication Console you are using See Section 5 2 1 for directions on starting and registering a publication server Step 2 For SMR only Select the Subscription node of the subscription for which you wish to update the schedule JH xDB Replication Console E File Publication Subscription Hi APRS e is S GJU OQAR ta Replication Servers General H Publication Server 192 168 2 7 9051 i A Subscription Server 192 168 2 7 9052 Property Zi Postgres Plus Advanced Server 192 1 Publication server i Publication server port es sales_dept Job type Scheduled time Previous fire time Next fire time Cron expression Figure 151 Selecting a subscription whose schedule is to be updated Copyright 2012 EnterpriseDB Corporation All rights reserved 228 Postgres Plus xDB Replication Server with Multi Master User s Guide Step 2 For MMR only Select the Publication Database node representing the master definition node for which you wish to update the schedule ts Replication Servers amp eS Publication Server 192 168 10 102 9051 Be SMR G GA MMR tR Postgres Plus Advanced
246. heduled job status H E EDB DEPT EE EDB EMP Figure 104 Selecting a subscription to remove Step 3 Remove the subscription in any of the following ways e Choose Remove Subscription from the Subscription menu e Click the secondary mouse button on the Subscription node and choose Remove Subscription e Click the primary mouse button on the Remove Subscription icon Replication Servers i e Publication Server 192 168 2 7 9051 eg Subscription Server 192 168 2 7 9052 Postgres Plus Advanced Server 192 1 ag sales_dept E E EDB DEPT EE EDB EMP Publication server Publication server port Scheduled job status Figure 105 Removing the subscription using the toolbar Copyright 2012 EnterpriseDB Corporation All rights reserved 158 Postgres Plus xDB Replication Server with Multi Master User s Guide Step 4 In the Remove Subscription confirmation box click the Yes button te Replication Servers e Publication Server 192 168 2 7 9051 S Subscription Server 192 168 2 7 9052 GR postgres Plus Advanced Server 192 tg S sales_dept H E EDB DEPT FE EDB EMP Figure 106 Remove Subscription confirmation The Subscription node no longer appears under the Subscription Database node Copyright 2012 EnterpriseDB Corporation All rights reserved 159 Postgres Plus xDB Replication Server with Multi Master User s Guide tq Replication Servers Ea S Publication Server
247. ho E dept Tree a 8 Databases 3 El emo edb eg subdb H Catalogs 4 E Extensions 3 GI gt Schemas 2 i E 9 edb Domains 0 FTS Configurations 0 fj FTS Dictionaries 0 FTS Parsers 0 IE FTS Templates 0 D Functions 0 sia Packages 0 rN Procedures 0 D D maia 0 B H 2a a F em D beian Functions 0 m Figure 84 Table definitions in the subscription database 5 3 4 Metadata Created for a Subscription You will notice schemas edb replicator puband edb replicator sub in the xDB Control database Schema edb replicator pub and its database objects were created when the first publication database definition was added Schema _edb replicator sub and its database objects were created when the first subscription database definition was added Copyright 2012 EnterpriseDB Corporation All rights reserved 140 Postgres Plus xDB Replication Server with Multi Master User s Guide File Edit Plugins View Tools Ti ABOI SLO vee Object browser x as E Properties x Statistics H Server Groups G Servers 1 F Postgres Plus Advanced Server 9 1 localhost 5 a 8 Databases 3 i S edb subdb 5 0 xdb H Catalogs 4 E Extensions s 3 H p eae peaks _pub H _edb_replicator_sub H _edb_scheduler 4 public Schema Owner _edb replicator_pub enterprisedb _edb_replicator_sub enterpr
248. hot influences the behavior of the batchInitialSync option as explained in the following section After the first replication completes to the target subscription or master node has initial snapshot is changed to Y by xDB Replication Server batchInitialSync The batchInitialSync option is used to control whether the first synchronization after loading the target tables from an offline snapshot is done in batch mode the default or non batch mode Set the batchInitialSync option to false to perform synchronization replication in non batch mode The of flineSnapshot configuration option must have first been set to true prior to creating the subscription or adding the additional master node A non batch mode synchronization occurs only if batchInitialSync is false and the has initial snapshot column in the xDB Control database is set to a value of O as described for the of flineSnapshot option batchInitialSync true false The default value is true 7 7 3 Single Master Replication Offline Snapshot An offline snapshot can be used to initially load the subscription tables of a single master replication system For a publication that is intended to have multiple subscriptions it is possible to create some of the subscriptions using the default xDB Replication Server snapshot replication process as described in Section 5 4 1 while other subscriptions can be created from an offline snapshot The following steps
249. hover ssesssssessessseseseeesssetsseessresseesseeessseesseese 163 5 6 1 Controlled Switchover Overview 4 ction hu eet 163 5 6 2 Controlled Switchover Stepsisivcssisisesicse esascisasenciashavadsaseasnceesencaedsceendeaswatane 164 5 7 Performing Failo yet sensn a a Ee a a EE e oa aie 166 5 8 Optimizing Performance cccscccesssesrcesesrcessseegMlileess E ooo 167 5 8 1 Optimizing Snapshot Replication sssssssessesteeneseeesssesdnresseesseessesessstessees 167 5 8 2 Optimizing Synchronization Replication ec eeecceeeeeeeceeeeeseneeeeneeeeeaes 170 6 Multi Master Replication Operation ccceescecesscecssneeceeeceestneecseeceseneeeesteeeesaeees 178 6 1 Prerequisite SPs cccccessceseecceessr Oe E OT L 178 6 1 1 Preparing the Master Definition Node ieee ceeseeeseeeseceseeeeeeeeseeeeaeens 178 6 1 2 Preparing Additional Master Nodes cee eeseceseeseceeeneecseeceeeeeeeeeneeesaeens 179 6 1 3 Verifying Host Accessilglity Fo Bec cece ccceeseccesscecosteccerteecenseesontees 180 6 2 Creating ggMMiimation Fae ee Bee eee cceeecceeseecensensoneeecenseecenseesontees 182 6 2 1 Registering a Publication Sige cesscssssccscsscsssssceensneeenees 182 6 2 2 Adding the Master Definition Node 2000 00 eee eeeceeceeceeceeececeeeeeceteeeesteeeesaes 183 o ing a gt LITO i o cscscccessccssscsesssrcesssecesssssessscesenaccesscessnacesenees 186 6 3 Creating Additional Master Nodes cc
250. ibed in the second bullet point be sure the publication tables are defined identically to the tables in the master definition node including schema names table names number of columns column names column data types column lengths primary key definitions unique constraints foreign key constraints etc The examples used throughout the rest of this user s guide are based on the following e The database user name of the second master node is mmruser e The database name of the second master node is mmrnode Step 1 Create a database user name for the master node This user becomes the owner of xDB Replication Server metadata database objects that will be created in the master node to track control and record the replication process and history The xDB Replication Copyright 2012 EnterpriseDB Corporation All rights reserved 179 Postgres Plus xDB Replication Server with Multi Master User s Guide Server metadata database objects are created in a schema named _edb replicator pub When creating the publication database definition for the master node the database user name is entered in the Publication Service Add Database dialog box see Section 6 3 CREATE ROLE mmruser WITH LOGIN SUPERUSER PASSWORD password Step 2 Create a database that will be used as the master node if such a database does not already exist CREATE DATABASE mmrnode 6 1 3 Verifying Host Accessibility If
251. icator pubi icator pub icator pub NG ator youl icator pub icacor pubi IGEN jele GEieOre joule We ators pub erep pub database erep mmr pub group erep publications erep pubtables ignoredcols erep publication subscriptions erep events erep events status ewe pec On mlaKeias erep conflicts options ergo Cleanup Coin erep ipULDEreSpIlog ercepipeUbitablerreplog erne pis UbESOryens EMA edb replicator sub CASCADE nedbiuepiliicacony sub nares pmconmmonmsec erep publication subscriptions NOTICE drop cascades to 7 other objects DETAIL drop cascades to sequenc dwopmcasicades seo rab lie gedberepinicalonesub iene pmcubmdatabace ekoo Cascella To table eclo raplicetor sto rreo tables dropiceoc cades ito table mocha pili at orie Ubi reps USC raipErOnS dropieoccadesito table iiedbirepikheoatorni ubir repistbs eripi onieaoIeS erop Cascades To table eclo replicator swo Trao TZIE drop Castecbes TO table eclo replicator stigs DROP SCHEMA Note If the publication server and the subscription server are running on separate hosts with their own xDB Control database the first DROP SCHEMA statement of Step 7 is performed on the xDB Control database of the publication server The second DROP SCHEMA statement of Step 7 is performed on the xDB Control database of the subscription server Step 8 Start the publication server Step 9 Start the subscription server Step 10 In the replication
252. idually committed In that way if an insertion of a row fails due to a duplicate key error that statement alone is rolled back Copyright 2012 EnterpriseDB Corporation All rights reserved 308 Postgres Plus xDB Replication Server with Multi Master User s Guide The error does not affect the other shadow table updates that must be applied since all updates are enclosed within their own individual transactions The batchInitialSync configuration option controls whether the first synchronization replication occurs in batch or non batch mode If you are using an offline snapshot to add a subscription or an additional master mode in an active replication system where updates are occurring to the source tables and transactions are thus accumulating in the shadow tables it is advisable to set batchInitialSync to false to perform the first synchronization replication in non batch mode If you are using offline snapshots to initially create the entire replication system that has yet to be activated and the content of the offline snapshots are all assumed to be consistent for the source and target tables then batchInitialSync can be left with its default setting of true since it is assumed that the first synchronization replication will not apply any duplicate updates 7 7 2 Offline Snapshot Configuration Options The following are the configuration options that you need to modify when using an offline snapshot Note These optio
253. iguration file contains the connection and authentication information used by any publication server or subscription server running on the host containing the file Specifically the xDB Replication Configuration file is accessed in the following circumstances e When a publication server or subscription server is started on the host e When a publication server or subscription server is registered during the process of creating a replication system Registration of a publication server or subscription server is done using the xDB Replication Console or the xDB Replication Server Command Line Interface Copyright 2012 EnterpriseDB Corporation All rights reserved 29 Postgres Plus xDB Replication Server with Multi Master User s Guide The xDB Replication Configuration file and its initial content are created when you install a publication server or subscription server on a host during the xDB Replication Server installation process The following is an example of the content of an xDB Replication Configuration file user enterprisedb port 5444 password ygJ 9AxoJEX8 54elcVIJPTw type enterprisedb host localhost database xdb Note The password for the database user name is encrypted Should you change this user name s password in the Postgres database server you must modify the password entry in the xDB Replication Configuration file to contain the encrypted form of the new password See Section 9 3 2 for directions on how
254. ine if there is still pending data to replicate In addition you can create a schedule for your replication system xDB Replication Server initiates and performs replications regularly according to the assigned schedule This allows you to run the replication system unattended See Section 7 1 for directions on creating a schedule 2 2 6 Snapshot and Synchronization XDB Replication Server performs replications using two different methods These methods are called snapshot replication and synchronization replication In either method the source tables refer to the tables from which the replication data is originating the publication in a single master replication system or the master node whose changes are being replicated to another master node in a multi master replication system Copyright 2012 EnterpriseDB Corporation All rights reserved 22 Postgres Plus xDB Replication Server with Multi Master User s Guide The target tables are the tables that are receiving the replication data from the source tables the subscription tables in a single master replication system or the master node receiving changes from another master node in a multi master replication system In snapshot replication all existing rows in the target tables are deleted using the database system s TRUNCATE command The tables are then completely reloaded from the source tables of the publication In synchronization replication only the changes inserts
255. information is determined during the subscription server installation process When viewed in the xDB Replication Console a registered subscription server appears under the top level Replication Servers node in the replication tree All subscription related logical components are created subordinate to a registered subscription server and appear underneath it in the replication tree Section 5 3 1 gives directions for registering a subscription server 2 3 2 6 Subscription Database Definition Note The subscription database definition applies only to single master replication systems You do not create a subscription database definition when creating a multi master replication system Subordinate to a registered subscription server one or more subscription database definitions can be created A subscription database definition identifies a database to which a publication s tables and views are to be replicated The identify information consists of the database server IP address port number a database user name and password and the database identifier The subscription server uses this information to connect to the subscription database to create the table definitions The publication server also uses this information to connect to the subscription database when it performs replications Section 5 3 2 discusses creating a subscription database definition Copyright 2012 EnterpriseDB Corporation All rights reserved 36 Po
256. ing for connections user The subscription database user name encrypted pwd The password of the database user in encrypted form See Section 8 3 4 for directions on using the encrypt command to generate an encrypted password pwdfile Copyright 2012 EnterpriseDB Corporation All rights reserved 353 Postgres Plus xDB Replication Server with Multi Master User s Guide The file containing the password of the database user in encrypted form oraconnectiontype Specify sid if the Oracle system ID SID is used to identify the subscription database in the database parameter Specify servicename if the Oracle service name is used to identify the subscription database in the database parameter dbname The Postgres or SQL Server database name the Oracle SID or the Oracle service name of the subscription database Examples In the following example an existing subscription database definition with subscription database ID 2 is updated java jar edb repcli jar updatesubdb repsvrfile subsvrfile prop gt Silo clio cl ae gt cloagse O2 16S 2o lio Once S4 N gt dbuser subuser dbpassfile pwdfile gt database subdb Updating subscription database Subscription database with ID 2 is updated successfully 8 3 30 Removing a Subscription Database removesubdb For SMR only The removesubdb command removes a subscription database definition Synopsis removesubdb repsvrfile subsvrfile subdbid dbid
257. ing the master definition node Copyright 2012 EnterpriseDB Corporation All rights reserved 217 Postgres Plus xDB Replication Server with Multi Master User s Guide Step 4 In the Set as MDN confirmation box click the Yes button Replication Servers Q Publication Server 192 168 10 102 9051 MUR Host E 192 168 10 103 QP Postgres Plus Advanced Server 192 amp emp_pub tgres Plus Advanced Server 192 emp_pub Figure 141 Set as MDN confirmation Step 5 The selected master node is now the master definition node as can be verified by the value Yes in the MDN field of the Property window Note The new master definition node is moved to the top of the replication tree in the xDB Replication Console Copyright 2012 EnterpriseDB Corporation All rights reserved 218 Postgres Plus xDB Replication Server with Multi Master User s Guide CE x08 Replication Console Build 57 File Publication Subscription Help g Replication Servers lt General Publication Server 192 168 10 102 9051 GPa MMR Property E Postgres Plus Advanced Server 1 Host 192 168 10 103 h R Postgres Plus Advanced Server 1 Port 5444 Ed SMR Database mmrnode User mmruser MDN Yes Publication count 1 Scheduled job status Not available Figure 142 Selected master node set as new master definition node Note You should now perform a synchronization replication to ensure that the new master defin
258. ion 7 4 2 for information on cleaning up the shadow tables 7 4 Managing History xDB Replication Server maintains two types of history Replication history is a summary record of each replication Shadow table history is a record of each change insert update or delete that was applied to each target table during synchronization replications Copyright 2012 EnterpriseDB Corporation All rights reserved 242 Postgres Plus xDB Replication Server with Multi Master User s Guide 7 4 1 Scheduling Shadow Table History Cleanup A preference can be set for each publication database definition to determine if and when shadow table history cleanup should be scheduled for all publications appearing under its corresponding Publication Database node Shadow table history cleanup has no benefit for snapshot only publications so if all of your publications under a Publication Database node are snapshot only publications then scheduled shadow table history cleanup should be disabled following steps 1 through 4 Replication history is not deleted by scheduling shadow table history cleanup Whenever a new publication database definition is created there is a scheduled default setting of every Sunday at 12 00 AM midnight for shadow table history cleanup Note A configuration option is available to force shadow table history cleanup after every synchronization replication See Section 9 3 1 8 for information on this option For Oracle only For s
259. ion All rights reserved 132 Postgres Plus xDB Replication Server with Multi Master User s Guide Register Subscription Server r l Host 192 168 2 7 Port 9052 User Name enterprisedb Password V Save login information Figure 76 Register Subscription Server dialog box Click the Register button after you have filled in the fields A Subscription Server node appears in the replication tree of the xDB Replication Console to Replication Servers Ej Publication Server 192 168 2 7 9051 cenera subscrpton Databases SMR Property G g Oracle 192 168 2 6 1521 xe pubuser Service status Running sales_dept Authentication Passed E EDB DEPT Subscription database count 0 ey EDB EMP CA MMR Figure 77 Replication tree after registering a subscription server 5 3 2 Adding a Subscription Database The database in which subscriptions are to reside must be identified to xDB Replication Server This is done by creating a subscription database definition After the subscription database definition is created a Subscription Database node representing that subscription database definition appears in the replication tree of the xDB Replication Console Subscriptions created subordinate to this subscription database Copyright 2012 EnterpriseDB Corporation All rights reserved 133 Postgres Plus xDB Replication Server with Multi Master User s Guide definition will have their p
260. ion server are running on the same host hence only one entry is needed for database subdb If the publication server and subscription server are running on separate hosts with their own xDB Control database on each host then the pg_hba conf file on the subscription database server looks like the following TYPE DATABASE USER CIDR ADDRESS METHOD Copyright 2012 EnterpriseDB Corporation All rights reserved 114 Postgres Plus xDB Replication Server with Multi Master User s Guide local is for Unix domain socket connections only local all all md5 IPv4 local connections host xdbsub enterprisedb 192 168 2 7 32 md5 host xdbsub enterprisedb 192 168 2 8 32 md5 host subdb subuser 19 16852 7 32 md5 host subdb subuser 19 WG 2a E md5 host all all 127 050 5 1 32 md5 IPv6 local connections host all all Se AES md5 Reload the configuration file after making the modifications Choose Reload Configuration Expert Configuration then Reload Configuration on Advanced Server from the Postgres application menu This will put the modified pg_hba conf file into effect Postgres Publication Database For a Postgres publication database the following is needed to allow access to the publication database host pub_dbname pub_dbuser pub_ipaddr 32 md5 host pub dbname pub_dbuser sub_ipaddr 32 md5 The value you substitute for pub dbname is the name of the Postgres publication database you intend to use The value you su
261. ions Choose Reload Configuration Expert Configuration then Reload Configuration on Advanced Server from the Postgres application menu This will put the modified pg_hba conf file into effect 5 2 Creating a Publication Creating your first publication requires the following steps e Registering the publication server e Adding the publication database e Creating a publication by choosing the tables and views for the publication along with creating any optional filter clauses Once the publication database has been added as many publications can be created as there are available tables and views that are readable by the publication database user and that meet the criteria outlined in sections 2 4 2 and 2 4 3 5 2 1 Registering a Publication Server When you register a publication server you are identifying the network location user name and password of a specific running publication server instance that you want to use to manage all aspects of the publications you will be creating subordinate to it It is important that you record the login information for the publication server as you must always use this same publication server instance to manage all publications created subordinate to it as represented in the xDB Replication Console replication tree Step 1 Start the publication server if it is not already running Note If you are using Oracle publication or subscription databases and the publication server has not been res
262. iption server is stored in its respective xDB Control database Note Once a publication server or subscription server is used in a replication system do not change the xDB Control database referenced within the publication or subscription server s respective xDB Replication Configuration file otherwise the replication system metadata will not be accessible to the publication server or subscription server thereafter The metadata stored in the xDB Control database includes information such as type of replication system single master or multi master network location database type and connection information for publication databases subscription databases and master nodes names of publications and the tables and views they contain names of subscriptions and the publications subscribed to and replication history Each publication database in a single master replication system also contains metadata regarding the changes that have been made to rows in the publication and the status of whether or not those changes have been applied to the subscription tables Similarly for a multi master replication system each master node contains metadata regarding the changes that have been made to rows in the publication residing on that master node and the statuses of whether or not those changes have been applied to the other master nodes in the multi master replication system 2 3 1 4 xDB Replication Configuration File The xDB Replication Conf
263. is the master and the subscription is the slave In a master to slave relationship changes are propagated in one direction only from the master to the slave Copyright 2012 EnterpriseDB Corporation All rights reserved 19 Postgres Plus xDB Replication Server with Multi Master User s Guide Subscription 1 Can update rows in publication tables but not in subscription tables Publication Database Subscription Slave Database Master Figure 6 Single Master Master to Slave replication Generally changes must not be made to the definitions of the publication tables or the subscription tables If such changes are made to the publication tables they are not propagated to the subscription and vice versa unless the DDL change replication feature is used as described in Section 7 6 If changes are made to the table definitions without using the DDL change replication feature there is a risk that future replication attempts may fail Changes must not be made to the rows of the subscription tables If such changes are made they are not propagated back to the publication If changes are made to the subscription table rows it is fairly likely that the rows will no longer match their publication counterparts There is also a risk that future replication attempts may fail 2 2 4 Multi Master Replication As an alternative to the single master master to slave replication model xDB Replication Server supports multi master
264. iseDB Corporation All rights reserved 288 Postgres Plus xDB Replication Server with Multi Master User s Guide In addition for synchronization replication triggers are generated on the publication tables that use certain attributes of these tables If the table definition is changed the trigger may no longer function properly Note Do not change the triggers generated by xDB Replication Server If it becomes necessary to regenerate the triggers you must remove the associated publication and then recreate the publication Note Certain table definition changes can be made and propagated by xDB Replication Server by using the DDL change replication feature See Section 7 6 for information on the DDL change replication feature If you do not use the DDL change replication feature then the following general steps must be taken if table definition changes are made In a single master replication system if changes were made to the definitions of one or more publication tables the resolution to the problem must be handled on a case by case basis as it depends upon the type of changes that were made In the worst case scenario the subscription and publication must be removed and recreated as follows e Remove the subscription that is associated with the publication See Section 5 5 4 for directions to remove a subscription e Remove the subscription tables from the subscription database This is done with SQL DROP TABLE statements in the d
265. isedb _edb_scheduler enterprisedb public enterprisedb Figure 85 Schemas containing metadata database objects in the xDB Control database Do not delete any of these database objects as the replication system metadata will become corrupted When you remove all subscriptions and subscription database definitions using the xDB Replication Console or xDB Replication Server CLI schema edb replicator sub and all of its database objects are deleted from the xDB Control database When you remove all publications and publication database definitions using the xDB Replication Console or xDB Replication Server CLI schema edb replicator pub and all of its database objects are deleted from the xDB Control database 5 4 On Demand Replication After a publication and subscription are created there are a couple of choices for starting the replication process e Replication can be done immediately by taking an on demand snapshot e Replication can be scheduled to start at a later date and time by creating a schedule Copyright 2012 EnterpriseDB Corporation All rights reserved 141 Postgres Plus xDB Replication Server with Multi Master User s Guide This section discusses the procedure for initiating a replication on demand Section 7 1 discusses how to create a schedule 5 4 1 Performing Snapshot Replication The very first replication must be performed using snapshot replication After the first snapshot replication subseq
266. ist a syntax summary of all commands See Section 8 3 1 for details on the help command 8 2 3 Supplying the Publication or Subscription Server Login Information This section discusses the syntax and usage of an xDB Replication Server CLI parameter required by many commands named repsvrfile Using parameter repsvrfile is the XDB Replication Server CLI equivalent for the process of registering the publication server or the subscription server in the xDB Replication Console Copyright 2012 EnterpriseDB Corporation All rights reserved 315 Postgres Plus xDB Replication Server with Multi Master User s Guide Section 5 2 1 discusses how the first step in building a replication system is to register the publication server In the xDB Replication Console the registered publication server appears as a node in the replication tree The Publication Server node provides a context to which you can add other logical components of the replication system When using the xDB Replication Server CLI there is no replication tree image available with which to relate the other logical components of the replication system Instead whenever you execute an xDB Replication Server CLI command that requires the context of a publication server or subscription server you must specify the publication server s login information or the subscription server s login information by means of the repsvrfile parameter The repsvrfile parameter takes as its value th
267. ith the network IP address 192 168 2 7 instead of the loopback address 127 0 0 2 192 EEs 2 6 T opensuse vm vmplanet net opensuse vm Copyright 2012 EnterpriseDB Corporation All rights reserved 111 Postgres Plus xDB Replication Server with Multi Master User s Guide PLA 5 Oa opensuse vm vmplanet net opensuse vm On some Linux systems you may need to restart the network service after you have modified the etc hosts file This may be done a number of different ways depending upon the Linux system you are using as shown by the following variations service network restart etc init d networking restart sudo etc init d networking restart The following example illustrates the service network command S et TOOL Password service network restart The hostname i command now returns the network IP address of the host hostname i LOY EE 2 5 Tl 5 1 4 3 Postgres Server Authentication A Postgres database server uses the host based authentication file pg_hba conf to control access to the databases in the database server You need to modify the pg_hba conf file in the following locations e On each Postgres database server that contains an xDB Control database e Oneach Postgres database server that contains a Postgres subscription database e On each Postgres database server that contains a Postgres publication database In a default Postgres installation this file is located in the directory POSTGRES_ INSTALL
268. ition node is synchronized with the other master nodes See Section 6 5 2 for directions on performing a synchronization replication 6 10 Optimizing Performance Various publication server configuration options are available to optimize the performance of multi master replication systems Almost all publication server performance related configuration options for single master replication systems are equally applicable to multi master replication systems except when they are database produce specific such as for Oracle See Section 5 8 for a discussion of these options The publication server configuration options are set in the publication server configuration file See Section 9 3 1 for a detailed explanation of how to set the configuration options in this file The following are some additional configuration options applicable to multi master replication systems only uniquenessConflictDetection The uniquenessConflictDetection option determines if uniqueness conflict needs to be detected at data load time or should be deferred to when data is applied against a target master node Possible values are EAGER and LAZY Set it to EAGER if there is a high probability of duplicate inserts across master nodes uniquenessConflictDetection EAGER LAZY Copyright 2012 EnterpriseDB Corporation All rights reserved 219 Postgres Plus xDB Replication Server with Multi Master User s Guide The
269. itle VARCHAR 20 Copyright 2012 EnterpriseDB Corporation All rights reserved 348 Postgres Plus xDB Replication Server with Multi Master User s Guide The replicateddl command is executed using the addcolumn sql file to update the triggers and shadow tables on the master nodes java jar edb repcli jar replicateddl emp pub gt repsvrfile pubsvrfile prop gt table edb emp gt ddlscriptfile addcolumn sql DDL changes successfully replicated to all master nodes 8 3 26 Adding a Subscription Database addsubdb For SMR only The addsubdb command adds a subscription database definition Synopsis addsubdb repsvrfile subsvrfile dbtype oracle enterprisedb postgresql sqlserver dbhost host dbport port dbuser user dbpassword encrypted pwd dbpassfile pwdfile oraconnectiontype sid servicename database dbname The addsubdb command creates a new subscription database definition The addsubdb command displays a unique subscription database ID that is assigned to the newly created subscription database definition The subscription database ID is used to identify the subscription database definition on which to operate when running other xDB Replication Server CLI commands See Section 5 3 2 for details on the database connection information that must be supplied when adding a subscription database definition Parameters subsvrfile The file containing the subscription serve
270. ity relationship diagram the emp table has a foreign key constraint referencing the dept table and the jobhist table has two foreign key constraints One constraint references the emp table and the other references the dept table If all three tables are in the publication then you can remove the following combinations of tables e Remove the jobhist table only e Remove both the jobhist table and the emp table Step 1 Make sure the publication server whose node is the parent of the publication you wish to change is running and has been registered in the xDB Replication Console you are using See Section 5 2 1 for directions on starting and registering a publication server Step 2 For SMR only Select the Publication node of the publication from which you wish to remove tables Step 2 For MMR only Select the Publication node under the Publication Database node representing the master definition node ta Replication Servers Publication Server 192 168 2 7 9051 B d SMR i a Oracle 192 168 2 6 1521 xe pubus publication schema ty Table count EDB DEPT Subscription count EDB EMP H E EDB JOBHIST LPA MMR S E Subscription Server 192 168 2 7 9052 R Postgres Plus Advanced Server 192 1 General Realtime Monitor Replication H Figure 201 Selecting a publication from which to remove tables Step 3 Open the Remove Tables dialog box in any of the following ways e From the Publication menu choos
271. ization replication JDBC batch syncBatchSize n The default value for nis 100 syncFetchSize The syncFetchSize option controls how many rows are fetched from the publication database in one network round trip For example if there are 1000 row changes available in the shadow tables the default fetch size requires 5 database round trips Using a fetch size of 500 retrieves all changes in 2 round trips Fine tune the performance by using a fetch size that conforms to the average data volume consumed by rows fetched in one round trip syncFetchSize n The default value for n is 200 txSetMaxSize The txSetMaxSize option defines the maximum number of transactional rows that can be grouped in a single transaction set The publication server loads and processes the changes by fetching as many rows in memory as grouped in a single transaction set A higher value is expected to boost performance However a very large value might result in an out of memory error Increase decrease the value in accordance with the average row size low high txSetMaxSize n The default value for nis 10000 enablePerformanceStats Set enablePerformanceStats option to true only if you need to conduct performance testing and analyze the replication statistics When enabled the publication server creates additional triggers on the publication tables in each master node The triggers produce transaction statistics that are recorded in the mmr transaction history t
272. jar edb repserver jar subserver 9052 user C6 2 ORO OTO 3996 684 pts 1 Rt LR Ss 0 00 grep subserver S su enterprisedb Password etc init d edb xdbsubserver restart Subscription Service stopped Password Subscription Service started For Windows only Open Control Panel Administrative Tools and then Services Use the Start or Restart link for the service named Subscription Service Copyright 2012 EnterpriseDB Corporation All rights reserved 131 Postgres Plus xDB Replication Server with Multi Master User s Guide File Action View Help es EIS cil m au p i Services Local Services Local Subscription Service for xDB Name Description Status b Replication Server Subscription Service for xDB Replication Server Provides da tiesi Superfetch Maintains a S System Event Notification Service Monitors sy Started S Tablet PC Input Service Enables Tab ie gi P Task Scheduler Enables aus Started rovides data replication services f from Oracle tm to Postgres Plus and TCP IP NetBIOS Helper Provides su Started vice versa Telephony Provides Tel Si Themes Provides us Started Figure 75 Windows subscription service Step 2 Register the subscription server Open the xDB Replication Console from the system s application menu Step 3 Select the top level Replication Servers node From the File menu choose Subscription Server and then choose Register Server
273. java jar edb repcli jar repversion repsvrfile pubsvrfile prop Burkgaromi Copyright 2012 EnterpriseDB Corporation All rights reserved 320 Postgres Plus xDB Replication Server with Multi Master User s Guide 8 3 4 Encrypting Passwords encrypt The encrypt command encrypts the text supplied in an input file and writes the encrypted result to a specified output file Use the encrypt command to generate an encrypted password that can be copied into a text file that will be referenced by an xDB Replication Server CLI command that requires a user name and the user s password Synopsis encrypt input infile output pwdfile The text in infile is processed using the MD5 encryption algorithm and the encrypted text is written to file pwdfile Make sure that infile contains only the text that you want to encrypt and that there are no extraneous characters or empty lines before the text or after the text that you want to encrypt Parameters infile The file containing the text to be encrypted pwdfile The file containing the encrypted form of the text from infile Examples The file infile contains the word password password The encrypt command is then executed producing a file named pwdfile java jar edb repcli jar encrypt input infile output pwdfile The content of file pwdfile contains the encrypted form of password ygJ9AxoJEX854e1lcVIJPTw 8 3 5 Adding a Publication Database addpubdb The addpubd
274. l if the database is a PostgreSQL database or an Advanced Server database in PostgreSQL compatible configuration mode Specify sqlserver if the database is a Microsoft SQL Server database host The IP address of the host on which the publication database server is running port The port number on which the database server is listening for connections user The publication database user name Copyright 2012 EnterpriseDB Corporation All rights reserved 322 Postgres Plus xDB Replication Server with Multi Master User s Guide encrypted pwd The encrypted password of the publication database user See Section 8 3 4 for directions on using the encrypt command to generate an encrypted password pwdfile The file containing the encrypted password of the publication database user oraconnectiontype Specify sid if the Oracle system ID SID is used to identify the publication database in the database parameter Specify servicename if the Oracle service name is used to identify the publication database in the database parameter dbname The Postgres or SQL Server database name the Oracle SID or the Oracle service name of the publication database repgrouptype Specify s if this command applies to a single master replication system Specify m if this command applies to a multi master replication system If omitted the default is s replicatepubschema For MMR only Applies to master nodes other than the master definition no
275. lause For SMR only A filter clause on a publication table can be removed Step 1 Make sure the publication server whose node is the parent of the publication you wish to change is running and has been registered in the xDB Replication Console you are using See Section 5 2 1 for directions on starting and registering a publication server Step 2 Click the secondary mouse button on the Table node of the table whose filter clause you want to remove and choose Remove Filter Clause Copyright 2012 EnterpriseDB Corporation All rights reserved 286 Postgres Plus xDB Replication Server with Multi Master User s Guide FOE ba Replication Servers G St Publication Server 192 168 2 7 9051 amp Bd sur 5 g Oracle 192 168 2 6 1521 xe pubu bode sales dent E no E a Subscription Server Remove Filter Clause Figure 213 Removing the filter clause from the selected table Step 3 Click the OK button in response to Filter Clause Has Been Removed Successfully The filter clause no longer appears on the General tab of the information window Copyright 2012 EnterpriseDB Corporation All rights reserved 287 Postgres Plus xDB Replication Server with Multi Master User s Guide File Publication Subscription Help Sq Replication Servers K General Replication History GE Publication Server 192 168 2 7 9051 i amp BS SMR Property GW Oracle 192 168 2 6 1521 xe pu
276. le subsvrfile prop gt subdbid 2 Printing SuDSCripe Tons dept_emp_ sub Copyright 2012 EnterpriseDB Corporation All rights reserved 356 Postgres Plus xDB Replication Server with Multi Master User s Guide 8 3 33 Taking a Single Master Snapshot dosnapshot For SMR only The dosnapshot command performs snapshot synchronization on the specified subscription in a single master replication system Synopsis dosnapshot subname repsvrfile subsvrfile See Section 5 4 1 for additional information on performing snapshot replication Parameters subname The name of the subscription for which the snapshot is to be taken subsvrfile The file containing the subscription server login information Examples In the following example snapshot replication is performed on subscription dept_emp_ sub java jar edb repcli jar dosnapshot dept emp sub gt repsvrfile subsvrfile prop Performing snapshot Source database connectivity info conn jdbc oracle thin 192 168 2 6 1521 xe user pubuser paso vorda as Target database connectivity info conn jdbc edb 192 168 2 7 5444 subdb user subuser password x Connecting with source Oracle database server Connecting with target EnterpriseDB database server Importing redwood schema EDB Table List DEPT EMP Loading Table Data in 8 MB batches Disabling FK constraints amp triggers on edb dept before truncate Truncating table DEP
277. le but with different values If there is a sequence of consecutive changes that occur to the same table using the same operation such as inserting a set of rows into the same table populating the same columns the publication server may apply these changes using a prepared statement Otherwise each change is applied with its own individual SQL statement There are a number of server configuration options that control the characteristics of the JDBC batch along with if when and how often prepared statements are used These are discussed in the following sections defaultBatchUpdateMode The defaultBatchUpdateMode option controls whether the default mode is to use individual SQL statements in the JDBC batch update this mode of operation is referred to as BUS or to use prepared SQL statements in the JDBC batch update this mode of operation is referred to as BUP defaultBatchUpdateMode BUS BUP The default value is BUS switchBatchUpdateMode The switchBatchUpdateMode option controls whether or not the publication server dynamically switches between BUS mode and BUP mode during the replication process depending upon the type and sequence of updates it encounters in the shadow tables Copyright 2012 EnterpriseDB Corporation All rights reserved 170 Postgres Plus xDB Replication Server with Multi Master User s Guide switchBatchUpdateMode true false The default value is true
278. le 1 Post Installation Files edb repl conf Windows IXDB_HOME etc KDB Replication Configuration file ae Start stop or restart the publication server i uia Start stop or restart the subscription xdb pubserver conf XDB_HOME etc Publication server configuration file xdb_subserver conf XDB_HOME etc Subscription server configuration file pubserver log Linux var log xdb rep buildnn Publication server log file POSTGRES_HOME enterprisedb ee lpubserver log Windows edb_replicator buildnn Publication server log file subserver log Linux var log xdb rep buildnn Subscription server log file POSTGRES HOME enterprisedb ve subserver log Windows edb_replicator buildan Subscription server log file eee as USER_HOME enterprisedb edb s login fil eae replicator buildnn erver ours Note XDB_ HOME is the directory where xDB Replication Server is installed This is the same as the PostgreSQL or Advanced Server home directory if the default directory location was chosen during xDB Replication Server installation Note POSTGRES_ HOME is the home directory of the postgres operating system account enterprisedb for Advanced Server installed in Oracle compatible configuration mode In the buildnn subdirectory nn is the xDB Replication Server build number Note USER HOME is the home directory of the operating system account in use In the buildnn subdirectory nn is the xDB Replication Server build number 3 3
279. lict Resolution Options tab If during synchronization replication conflicting changes are pending against the same row from different master nodes the conflict resolution strategy determines which of the conflicting changes is accepted and replicated to all master nodes The conflicting changes that are not accepted are discarded If the selection from the Conflict Resolution Strategy column does not resolve the conflict the selection from the Standby Conflict Resolution Strategy column is applied If neither strategy resolves the conflict the event is marked as Pending in the Conflict History tab See Section 6 7 for information on viewing conflict history An example of a conflict is when the same column of the same row is changed by transactions in two different master nodes Depending upon the conflict resolution strategy in effect for the table one of the transactions is accepted and replicated to all master nodes The other transaction is discarded and not replicated to any master node The following is a brief summary of each conflict resolution strategy e Earliest Timestamp The conflicting change with the earliest timestamp is accepted and replicated to all other master nodes All other conflicting changes are discarded Copyright 2012 EnterpriseDB Corporation All rights reserved 188 Postgres Plus xDB Replication Server with Multi Master User s Guide e Latest Timestamp The conflicting change with the latest timestamp is
280. load Disabling indexes on edb dept before data load Loading Table dept dept Migrated 5 rows dept Table Data Load Summary Total Time s 0 247 Total Rows 5 Disabling FK constraints amp triggers on edb emp before truncate Truncating table emp before data load Disabling indexes on edb emp before data load Loading Table emp emp Migrated 14 rows emp Table Data Load Summary Total Time s 0 163 Total Rows 14 Enabling FK constraints amp triggers on edb dept Enabling indexes on edb dept after data load Enabling FK constraints amp triggers on edb emp Enabling indexes on edb emp after data load Performing ANALYZE on EnterpriseDB database Data Load Summary Total Time sec 0 8 Total Rows 19 Total Size MB 0 0 Schema edb imported successfully Migration process completed successfully Migration logs have been saved to var log xdb rep build571 KKEKKKKKKKKKKKKKK KK KK Migration Summary KEKKKKKKKKKKKKKKKKKK Tables 2 out Cir 2 Constraints 4 out of 4 Total objecto 6 Successful count 6 Failure Count 0 KKEKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKK Snapshot taken successfully 8 3 35 Performing a Synchronization dosynchronize The dosynchronize command performs synchronization replication on the specified subscription for a single master replication system or for an entire multi master replication sys
281. lude all tables and views in the Available Tables list in the publication Copyright 2012 EnterpriseDB Corporation All rights reserved 269 Postgres Plus xDB Replication Server with Multi Master User s Guide Add Tables Fiter Clause Pubicaton ae Figure 195 Add Tables dialog box If you wish to omit certain rows of the publication tables or views from being replicated follow the directions in the next step to create a filter otherwise go on to Step 6 Step 5 For SMR only If you want to filter the rows of the publication tables or views click the Filter Clause tab Enter an appropriate SQL WHERE clause in the text box next to a table or view to select the rows you want to replicate In the following example only rows where the deptno column contains 30 are included in replications All other rows are excluded from replication Copyright 2012 EnterpriseDB Corporation All rights reserved 270 Postgres Plus xDB Replication Server with Multi Master User s Guide Add Tables Publication sales dept Add Tables Filter Clause Specify a filter criteria to exclude table rows from replication The filter criteria is a SQL WHERE CLAUSE without WHERE keyword For example state CA Figure 196 Adding a filter clause Step 6 For SMR only Click the Add Tables button If Publication Updated Successfully appears click the OK button otherwise investigate the error and m
282. m s data dictionary as MyTable References to this table must be made using an uppercase M an uppercase T and lowercase letters for the rest of the name If a database object is created without the double quotes surrounding its identifier name default case translation of alphabetic characters occurs In Oracle the default case translation is to uppercase For example CREATE TABLE MyTable would result in an object identifier name of MYTABLE In Postgres the default case translation is to lowercase For example CREATE TABLE MyTable would result in an object identifier name of mytable 9 3 6 Replicating the SQL Server SQL_VARIANT Data Type This section discusses how to replicate a table containing the SQL Server SOL VARIANT data type The SQL VARIANT data type defines a column so that the individual values in that column may be of different data types For example the same SQL VARIANT column can store values that have been explicitly cast as character integer numeric and date time However if a table containing a SOL_ VARIANT column is to be replicated to a Postgres database the usage of the column in Postgres is restricted to a single data type to which all the values in the SQL _ VARIANT column are implicitly convertible that is without the use of explicit casting For example an integer value is implicitly convertible to a FLOAT data type but a floating p
283. master replication system A single publication in a Postgres Plus Advanced Server database contains tables from two schemas that are replicated to an Oracle database Copyright 2012 EnterpriseDB Corporation All rights reserved 42 Postgres Plus xDB Replication Server with Multi Master User s Guide vanced Server to Oracle replication syste Schema _edb_replicator_pub Objects Figure 15 Postgres Plus Advanced Server to Oracle replication The following describes the logical components in the preceding diagram e The publication server to be used is identified by registering its network location user name and password e A publication database definition is created subordinate to the SMR type node under the publication server The Postgres database user name pubuser is specified in the definition along with the database network location and database identifier The publication server creates schema edb replicator pub and populates it with database objects for the replication system s metadata when you create the publication database definition Copyright 2012 EnterpriseDB Corporation All rights reserved 43 Postgres Plus xDB Replication Server with Multi Master User s Guide e A publication named pub is created subordinate to the publication database definition The publication consists of table A in schema S1 and tables B and C in schema S2 e The subscription server to be used is identified by registering its netw
284. me The name of the publication whose tables are to be validated pubsvrfile The file containing the publication server login information repgrouptype Copyright 2012 EnterpriseDB Corporation All rights reserved 345 Postgres Plus xDB Replication Server with Multi Master User s Guide Specify s if this command applies to a single master replication system Specify m if this command applies to a multi master replication system Examples In the following example publication dept emp is validated java jar edb repcli jar validatepub dept _emp gt repsvrfile pubsvrfile prop repgrouptype s Validating publiceacionidept emp k All schema of published tables in Publication 0 are up to date 8 3 23 Validating All Publications validatepubs The validatepubs command checks if any of the definitions of the tables subordinate to the given publication database definition have changed since the publication was created Synopsis validatepubs repsvrfile pubsvrfile pubdbid dbid repgrouptype m s See Section 7 5 4 for additional information on validating publications Parameters pubsvrfile The file containing the publication server login information dbid The publication database ID of the publication database definition under which all publication tables are to be validated repgrouptype Specify s if this command applies to a single master replication system Specify m if this command applies to a mul
285. me members of publications e For publications that will use synchronization replication the publication database user can create triggers on the publication tables For Oracle the publication database user must have trigger creation privilege regardless of the replication method used though triggers will only be created for publications using synchronization replication The examples used throughout the rest of this user s guide are based on the following e The publication database user name is pubuser e The tables and view used in publications reside in a schema named edb e Three tables named dept emp and jobhist are members of schema edb e One view named salesemp is a member of schema edb This view is a SELECT statement over the emp table e The Oracle system identifier SID of the publication database is xe The SQL Server publication database name is edb The Postgres publication database name is edb The cases of Oracle as the publication database SQL Server as the publication database and Postgres as the publication database are presented with examples in this section For preparing an Oracle publication database see the next section For preparing a SQL Server publication database see Section 5 1 2 2 For preparing a Postgres publication database see Section 5 1 2 3 5 1 2 1 Oracle Publication Database Step 1 Create a database user name for the publication database user The publication database
286. mmunicating components are on the same host but if at some future point you decide to move a component to a different host on the network the loopback address stored as the component s network address in the metadata will no longer work for the component trying to make the connection For Linux only You may need to modify the etc hosts file so that a host s network IP address is associated with the host s name Note For an alternative to modifying the etc hosts file see Section 9 3 1 6 The default configuration on Linux systems associates the host name with the loopback address in the etc hosts file as shown by the following example TAO Ore opensuse vm vmplanet net opensuse vm This is also verified by using the hostname i command which returns the IP address associated with the host name hostname i TORON In these circumstances certain xDB Replication Server components will have trouble locating its other components on the network as in the following cases e When the user interface attempts to connect to the publication server or subscription server e When the subscription server attempts to connect to the publication server If the loopback address 127 x x x is returned such as in the preceding example edit the etc hosts file so that the network IP address is associated with the host name instead The following example shows the modified etc hosts file so that the host name opensuse vm is now associated w
287. mn dflt_ expr An expression for the default value of the column column constraint n A column constraint such as a UNIQUE or CHECK constraint Examples The following are examples of ALTER TABLE statements that can be used by the DDL change replication feature The following example adds a column named title to the edb emp table ALTER TABLE edb emp ADD COLUMN title VARCHAR2 20 The following example adds a column named gender with a CHECK constraint ALTER TABLE edb emp ADD COLUMN gender CHAR 1 CHECK gender IN M F The DDL change replication feature can be invoked from either the xDB Replication Console see Section 7 6 2 or the xDB Replication Server CLI see Section 8 3 25 The next section describes the process that occurs during DDL change replication Copyright 2012 EnterpriseDB Corporation All rights reserved 303 Postgres Plus xDB Replication Server with Multi Master User s Guide 7 6 1 DDL Change Replication Process The DDL statement is executed in a controlled manner such that the target table is exclusively locked by the default setting of configuration option ddlChangeTableLock during the course of the operation This is done to avoid loss of any transactions while the replication triggers and shadow table are modified by the DDL change replication process Only one target table is locked at a time while DDL change replication takes place on t
288. mple by using an SQL command line utility Doing so may cause the xDB Replication Console and xDB Replication Server CLI to become inoperable See Section 9 2 4 2 if this problem occurs Deleting the replication system logical components using the Copyright 2012 EnterpriseDB Corporation All rights reserved 52 Postgres Plus xDB Replication Server with Multi Master User s Guide xDB Replication Console or xDB Replication Server CLI automatically drops the metadata database objects from the physical database e The order of removal of a multi master replication system is as follows 1 Remove the replication system logical components using the xDB Replication Console or xDB Replication Server CLI starting with the publication database definitions of the master nodes other than the master definition node 2 Remove the publication from under the master definition node 3 Remove the publication database definition of the master definition node 4 After all replication system logical components have been removed except for possibly the publication server you can drop any of the physical database objects in Postgres Do not drop the metadata database objects manually for example by using an SQL command line utility Doing so may cause the xDB Replication Console and xDB Replication Server CLI to become inoperable 2 4 3 Restrictions on Replicated Database Objects When a subscription is created in a single master replication system the table
289. must be running before you can make any changes to the file See Step 1 of Section 5 3 1 for directions on starting the subscription server Step 2 Click the secondary mouse button on the Subscription Server node and choose Update The Update Subscription Server dialog box appears Copyright 2012 EnterpriseDB Corporation All rights reserved 149 Postgres Plus xDB Replication Server with Multi Master User s Guide User Name enterprisedb Password _ Save login information Update Cancel Figure 95 Update Subscription Server dialog box Step 3 Complete the fields in the dialog box according to your purpose for updating the server login file e Ifthe subscription server now runs on a host with a different IP address or port number than what is shown in the dialog box enter the correct information You must also enter the user name and password saved in the xDB Replication Configuration file that resides on the host identified by the IP address you entered in the Host field Check the Save Login Information box if you want the new login information saved in the server login file otherwise leave the box unchecked in which case access to the subscription server is available for the current session but subsequent sessions will require you to register the subscription server again e If you want to delete previously saved login information make sure the network location shown in the dialog bo
290. must be specified along with the pubdbid and pubsvr file parameters See Section 7 4 1 for additional information on creating a schedule for shadow table history cleanup Parameters pubdbid Publication database ID of the publication database definition for which a schedule is to be enabled or disabled for deleting shadow table history pubsvrfile The file containing the publication server login information disable If the disable parameter is specified then any existing shadow table history cleanup schedule is removed from the publication database definition If the disable parameter is not specified then enable must be specified enable Establish a schedule for shadow table history cleanup no_of hours The number of hours between scheduled shadow table history cleanup jobs This can be any integer between 1 and 12 inclusive hour The hour of the day based on a 24 hour clock This can be any integer from 0 to 23 day of week The day of the week This can be any of the following values SUNDAY MONDAY TUESDAY WEDNESDAY THURSDAY FRIDAY or SATURDAY This value is case insensitive so Sunday and sunday will work as well as SUNDAY Copyright 2012 EnterpriseDB Corporation All rights reserved 370 Postgres Plus xDB Replication Server with Multi Master User s Guide Examples In the following example shadow table history cleanup is scheduled to run once every 3 hours on the shadow tables created
291. n Console from the system s application menu SNe Places System B amp S amp Accessories i Graphics 4 Postgres Plus Add ons R xDB Replication Console P Postgres Plus Advanced Server 9 1 Q Programming M Sound amp video 2 System Tools Bi Add Remove Software Figure 63 xDB Replication Console menu option Copyright 2012 EnterpriseDB Corporation All rights reserved 118 Postgres Plus xDB Replication Server with Multi Master User s Guide LH xDB Replication Console Build 571 File Publication Subscription Help AR 3 Bnl 9 SSW Ogis K General Replcation Server Figure 64 xDB Replication Console Step 3 Select the top level Replication Servers node From the File menu choose Publication Server and then choose Register Server Alternatively click the secondary mouse button on the Replication Servers node and choose Register Publication Server The Register Publication Server dialog box appears Enter the values you supplied during the installation of xDB Replication Server unless otherwise specified e Host Network IP address of the host running the publication server This is the network IP address used for pub _ipaddr inthe pg_hba conf file in Section 5 1 4 3 Do not use localhost for this field e Port Port number the publication server is using This is the port number you specified on the Publication Server Details screen in Step 16 of Secti
292. n Operations seisein sE E ASE a EAE S AEE ain 221 7 1 Cre ati a Schedule ntn a e a doula a E eaten ane at 221 dad Managing a Sched les iiini e nA n E TA hoe cael arenas aa 228 Rc Updatins a Scheduled nin seca a at an eae eee ne 228 T22 REMONING a SCH AUS keresre iie ts nt ood e tai 231 yee Viewing Replication History is sscisivasesssecessacaseascsesdoaseonadee snccenentsaesatebeeenceesnaeees 235 Tad SAIL Replication History cissi e a antes Lass WT a Ea 235 7 3 2 Hiding Synchronizations With Zero Transaction Counts seeeeseeeeeeeeee 238 7 3 3 Shadow Table HIstory cceccsssesssreseseeese A e O d 240 TA Managing HIStory 00 0 cesses M ao T A R 242 7 4 1 Scheduling Shadow Table History Cleanup eecceeeeecsseeeeeteeeeeteeeees 243 7 4 2 Cleaning Up Shadow Table History 0 0 0 ceeeeeeccecseceeeneeeeessececseeeeesteeeees 247 7 4 3 Cleaning Up Replication History ccceseccecssccecneccecesececeeeeessseeeeeteeeees 252 7 5 Managing a Publication 4h F CT oeeo 256 7 5 1 Updating a Publication Server a eseeeeeseeseseesressrseresressrsererressesrrerresseesres 256 7 5 2 Updating a Publication Database fab sccscccsecccsscecoeesscerseeceneeecoeeees 262 7 5 3 Updating a RaDlication T oeeo reer eer reer roe 266 7 5 4 Validating a HRD ieMMMIn ccrsssrcsssscsesssssesssccessssesesscesessncessacesensceeenaceeens 288 Removing QABMOLICAUIQIMIIIM 0 0 cce
293. n containing the table or view whose filter clause is to be updated pubsvrfile The file containing the publication server login information schema t The name of the schema containing table name This value is case sensitive table name The name of the table whose filter clause is to be updated This value is case sensitive schema v The name of the schema containing view _name This value is case sensitive view_name The name of the view whose filter clause is to be updated This value is case sensitive filter clause The new filter clause to be used Examples The filter clause on Advanced Server table edb emp in publication analysts managers is modified to use the condition job IN ANALYST MANAGER AND sal gt 2500 java jar edb repcli jar updatefilterclause analysts managers gt repsvrfile pubsvrfile prop gt table edb emp filterclause job IN ANALYST MANAGER AND sal gt 2500 Updating table filter clause Filter clause has been updated successfully Copyright 2012 EnterpriseDB Corporation All rights reserved 340 Postgres Plus xDB Replication Server with Multi Master User s Guide 8 3 18 Removing a Filter Clause removefilterclause For SMR only The removefilterclause command deletes the filter clause from the specified table or view Synopsis removefilterclause pubname repsvrfile pubsvrfile table schema t table name schema v view name S
294. n its subordinate publications Similarly the Subscription Server nodes of saved subscription servers immediately appear in the replication tree allowing you to perform administrative tasks on its subordinate subscriptions If you did not save server login information the server nodes would not be visible in the replication tree You would have to re enter the server s network location user name and password In other words you would have to register the server each time you open the xDB Replication Console Note Each operating system account on a given host has its own server login file Thus the servers that are saved and appear in the xDB Replication Console when opened is independently determined for each operating system account Copyright 2012 EnterpriseDB Corporation All rights reserved 97 Postgres Plus xDB Replication Server with Multi Master User s Guide 4 2 2 Security Risks of Saved Server Login Information The preceding section discussed the benefits of saving server login information The security risk associated with it is if unauthorized persons gain access to your operating system account they could then potentially open the xDB Replication Console on your host using your operating system account If the login information of publication servers or subscription servers is saved the corresponding Publication Server nodes or Subscription Server nodes immediately appear in the xDB Replication Console with no re
295. n system components represented as nodes in an inverted tree e Information Window Tabbed window with information about a highlighted node in the replication tree Replication Tree Menu Bar Tool Bar Information Window LE DB Replication CgAsole Build 57 to Repiication Servers K General Replication Server Figure 54 xDB Replication Console window The options that are available on the menu bar and tool bar are dependent upon the node highlighted in the replication tree Only those options relevant to the highlighted node are available in the menu bar and tool bar The content of the information window applies to the highlighted node as well Copyright 2012 EnterpriseDB Corporation All rights reserved 92 Postgres Plus xDB Replication Server with Multi Master User s Guide 4 1 xDB Replication Console Tool Bar This section describes when the various tool bar icons are activated The operations associated with the tool bar are described in sections 5 2 and 5 3 for single master replication For multi master replication see Section 6 2 Note The publication server must be running in order to use tools relevant to publications Similarly the subscription server must be running in order to use tools relevant to subscriptions 4 1 1 Refresh The Refresh icon is always activated Click the Refresh icon if the replication tree or information window does not appear to display the lates
296. name of the table whose conflict resolution strategy is to be printed This value is case sensitive Examples In the following example the conflict resolution strategy on Advanced Server table edb emp in publication emp_pub is printed java jar edb repcli jar printconfresolutionstrategy emp pub gt repsvrfile pubsvrfile prop gt table edb emp Primary Standby Conflict Resolution Strategy Conflict Resolution Option Earliest Timestamp Standby Conflict Resolution Option Manual 8 3 20 Updating the Conflict Resolution Strategy updateconfresolutionstrategy For MMR only The updateconfresolutionstrategy command changes the conflict resolution strategy or standby conflict resolution strategy of the specified table Synopsis updateconfresolutionstrategy pubname srepsvrfile pubsvrfile table schema t table name conflictresolution E L N M standbyconflictresolution E L N M See Section 6 8 for additional information on updating the conflict resolution strategy Note The schema name and table or view name that you supply as values for the table parameter are case sensitive Unless quoted identifiers were used to build the database objects Oracle names must be entered using uppercase letters for example EDB DEPT and Advanced Server names must be entered in lowercase letters for example edb dept See Section 9 3 5 for additional information on quoted identifiers and
297. nations of a source database server and a target database server are not permitted for a publication and its associated subscription in a single master replication system The source refers to the database server of the publication database The target refers to the database server of the subscription database This section presents the specific combinations of database server configurations that can be used for a publication and its associated subscription 9 1 1 Advanced Server Compatibility Configuration Modes Postgres Plus Advanced Server supports two compatibility configuration modes of operation which are the following e Oracle compatible configuration mode Operations are performed using Oracle syntax and semantics for data types functions database object creation and so forth This mode is useful when your applications are migrated from Oracle or you want your applications built in an Oracle compatible fashion e PostgreSQL compatible configuration mode Operations are performed using native PostgreSQL syntax and semantics This mode is useful when your applications are migrated from PostgreSQL or you want your applications built in a PostgreSQL compatible fashion For more information on features supported in Oracle compatible configuration mode see the Oracle Compatibility Developer s Guide located on the Postgres Plus Documentation web page http www enterprisedb com learning documentation do The compatibility config
298. ng and has been registered in the xDB Replication Console you are using See Section 5 2 1 for directions on starting and registering a publication server Step 2 For SMR only Select the Publication Database node under which you want to validate all publications Step 2 For MMR only Select the Publication Database node representing the master definition node Step 3 From the Publication menu choose Validate All Publications Alternatively click the secondary mouse button on the Publication Database node and choose Validate All Publications Copyright 2012 EnterpriseDB Corporation All rights reserved 292 Postgres Plus xDB Replication Server with Multi Master User s Guide GH Publication Server 192 168 2 4 9051 eg Postgres Plus Advanced S aS H E edb dept Validate All Publication Figure 217 Validating all publications subordinate to a selected publication database Step 4 If there were no modified tables click the OK button Copyright 2012 EnterpriseDB Corporation All rights reserved 293 Postgres Plus xDB Replication Server with Multi Master User s Guide Figure 218 Successful validation of all tables in all publications subordinate to a selected publication database If there were modified tables a list of publications that contain the modified tables is displayed Determine which tables were changed and what changes were made to the table definitions These issues need to be resolved on a
299. ng replications are to be initiated for a multi master replication system Synopsis confschedulemmr pubdbid pubname pubname repsvrfile pubsvrfile remove realtime no of sec daily hour minute weekly day of week hour minute monthly month day of month hour minute cronexpr cron expression If the remove parameter is specified then the schedule is deleted from the publication No other parameters other than pubdbid pubname and repsvrfile can be specified in this case Copyright 2012 EnterpriseDB Corporation All rights reserved 363 Postgres Plus xDB Replication Server with Multi Master User s Guide If the remove parameter is omitted then one of parameters realtime daily weekly monthly or cronexpr must be specified along with the pubdbid pubname and repsvrfile parameters If there is an existing schedule for publication pubname it will be replaced by the new schedule See Section 7 1 for additional information on creating a schedule Parameters pubdbid The publication database ID of the publication database definition representing the master definition node on which to configure the schedule pubname The name of the publication for which a replication schedule is to be created pubsvrfile The file containing the publication server login information remove If the remove parameter is specified then any existing schedule is removed from the publication If the remove parameter is not
300. ng the publication server for a new subscription Verify you have entered the correct host IP address and port number of the server Verify the server is running see Section 9 2 4 1 If the server is running on Linux verify that in the etc hosts file the host name is mapped to the correct network IP address which matches the IP address returned by the Linux sbin ifconfig command and also matches the IP address you entered in the Host field of the dialog box Alternatively instead of modifying the etc hosts file set configuration option java rmi server hostname to the IP address of the publication or subscription server see Section 9 3 1 6 Do not use the loopback address 127 x x x for this entry The database cannot be registered because a partial schema already exists A manual cleanup is required to proceed Resolution The metadata database objects from a prior publication already exist in the schema under which the publication server is attempting to create new metadata database objects Perform the operation described in Section 9 2 4 2 Database cannot be removed Reason Publication database connection cannot be removed as one or more publications are defined against it Resolution Make sure all publications subordinate to the publication database definition have been removed If no publications appear under the Publication Database node in the xDB Replication Console replication tree and the error persists there may be a
301. nges to these attributes result in inaccurate replication system metadata which in turn may result in errors during subsequent replication attempts or replication system administration This section describes how to update the metadata stored for the subscription server the subscription database definition and subscriptions in order to keep the information consistent with the actual replication system environment 5 5 1 Updating a Subscription Server When you register a subscription server in the xDB Replication Console you may choose to save the subscription server s network location IP address and port number user name and encrypted password in a server login file on the computer on which you are running the xDB Replication Console See Section 4 2 for information on saving the login information The steps described in this section show you how to update the subscription server s login information in the server login file It is assumed that the xDB Replication Console is open on your computer and the subscription server whose login information you wish to alter in the server login file appears as a Subscription Server node in the xDB Replication Console s replication tree Copyright 2012 EnterpriseDB Corporation All rights reserved 148 Postgres Plus xDB Replication Server with Multi Master User s Guide File Publication Subscription Help guy eSa OSS g Replication Servers General Publication Databases
302. ning on host 192 168 10 102 192 169 10 102 opensuse vm vmplanet net opensuse vm iA te 0 OZ opensuse vm vmplanet net opensuse vm You can set the IP address in the server configuration file as shown by the following On Linux machines the localhost to real IP may not give correct results Hence users are advised to override the following property with server IP address java rmi server hostname 192 168 10 102 9 3 1 7 Using pgAgent Job Scheduling Note The option described in this section applies to the publication server only Note Using pgAgent job scheduling has significance only if Postgres is the publication database Note You must have pgAgent installed and running on the host where the publication database resides When the pgdbschedule option is set to true xDB Replication Server uses the pgAgent job scheduler instead of the default Quartz job scheduler When activated pgAgent takes over the following scheduling tasks from Quartz e Scheduling shadow table history cleanup in the publication database See Section 7 4 1 for information on scheduling shadow table history cleanup e Scheduling transaction set creation A transaction set creation job is scheduled to run every hour to create transaction sets from the updates on the source tables Transaction sets are applied to the target tables Unlike the Quartz scheduler pgAgent can still run and perform its tasks even if the publication server is not runnin
303. nize operation before you proceed to alter the Publication Do you want to continue Figure 198 Data Sync Check dialog box Step 7 The replication tree appears as follows with the newly added table under the Publication node g Replication Servers e eS Publication Server 192 168 2 7 9051 GB sur amp g Oracle 192 168 2 6 1521 xe pubu Name JOBHIST S E sales_dept Schema EDB E EDB DEPT PK attributes EMPNO STARTDATE E EDB EMP Attributes count 8 i E EDB JOBHIST Filter Clause deptno 30 o MMR Subscription Server 192 168 2 7 9052 Z QR Postgres Plus Advanced Server a924 Figure 199 Publication with added table Copyright 2012 EnterpriseDB Corporation All rights reserved 273 Postgres Plus xDB Replication Server with Multi Master User s Guide 7 5 3 2 Removing Tables From a Publication You can remove one or more tables from a publication but only if the following conditions are both true e There is no subscription associated with the publication e The tables to be removed are not parent tables referenced by foreign key constraints of child tables that are not selected for removal as well hiredate Sal comm deptno empno startdate Figure 200 Entity relationship diagram of tables with foreign key constraints Copyright 2012 EnterpriseDB Corporation All rights reserved 274 Postgres Plus xDB Replication Server with Multi Master User s Guide In the preceding ent
304. ns apply to the publication server only offlineSnapshot The of flineSnapshot option must be set to true before creating the subscription for a single master replication system or before adding the master node for a multi master replication system offlineSnapshot true false The default value is false When set to true the of flineSnapshot option prevents the usual creation of the subscription schema and table definitions when the subscription is defined in a single master replication system since it is assumed that you are creating the subscription table definitions and loading them from an external source other than the publication When adding the master node in a multi master replication system leave the Replicate Publication Schema and Perform Initial Snapshot boxes unchecked see Section 6 3 When of flineSnapshot is set to true this has the direct effect within the xDB Control database in schema edb replicator pub of setting column has initial snapshot to a value of O indicating an offline snapshot is used for the Copyright 2012 EnterpriseDB Corporation All rights reserved 309 Postgres Plus xDB Replication Server with Multi Master User s Guide target subscription or master node represented by the row Column has initial snapshot is setin table erep publication subscriptions fora single master replication system and in table erep_ mmr pub group for a multi master replication system The setting of has initial snaps
305. nt then a second internal repeat counter is incremented by one If the repeat counter eventually reaches bupBatchThresholdRepeatLimit the update mode is switched from BUP to BUS Thus if there are frequent consecutive changes of prepared SQL statements as measured against bupBatchThresholdRepeatLimit each of which is executed a small number of times as measured against bupBatchThresholdCount then the mode of execution changes back to individual SQL statements instead of prepared statements Note The publication server changes back to prepared statements when the threshold set by busBatchThresholdCount is met The following example illustrates the processing of updates when bupBatchThresholdCount is set to 3 and bupBatchThresholdRepeatLimit is set to 4 A change to the query domain referred to in this example means a different statement type INSERT UPDATE or DELETE or a different target table are encountered in the next update thus requiring the use of a different prepared SQL statement 1 INSERT INTO emp 2 INSERT INTO emp 3 INSERT INTO dept At this point the query domain is changed after the first two updates change from table emp to dept and the number of executions of the prior prepared statement 2 is less than bupBatchThresholdCount so the repeat counter is set to 1 INSERT INTO dept INSERT INTO dept INSERT INTO dept INSERT INTO emp HHO
306. nux so you will see use of the Linux continuation character which is a backslash to show how an xDB Replication Server CLI command can be continued onto the next line if you do not want to wrap the text in your terminal window For Windows use the Windows continuation character which is a caret 8 3 1 Getting Help help The help command provides a syntax summary of all xDB Replication Server CLI commands Synopsis Copyright 2012 EnterpriseDB Corporation All rights reserved 319 Postgres Plus xDB Replication Server with Multi Master User s Guide help Examples S java jar edb repcli jar help Usage java jar edb repcli jar OPTIONS Where OPTIONS include help Prints out Replication CLI command line usage version Prints out Replication CLI version encrypt input lt file gt output lt file gt Encrypts input file to output file repversion repsvrfile lt file gt Prints Replication Server version 8 3 2 Printing the Version Number version The version command provides the xDB Replication Server CLI s version number Synopsis version Examples java jar edb repcli jar version Versions Ii 8 3 3 Printing the xDB Replication Server Version Number repversion The repversion command provides the xDB Replication Server s version number Synopsis repversion repsvrfile pubsvrfile Parameters pubsvrfile The file containing the publication server login information Examples
307. o a Publication addtablesintopub ccceeeeeeeeeeeeeeteees 334 8 3 15 Removing Tables From a Publication removetablesfrompub 337 8 3 16 Printing a Filter Clause printfilterclause eee eeeececeeeeeeeeeeeeeteeeenseees 338 8 3 17 Updating a Filter Clause updatefilterclause 2 0 0 0 ceeeeeeseeeeeeeeeeeeeeeeeeees 339 8 3 18 Removing a Filter Clause removefilterclause eecceeeseeeeeeeeeeteeeeeeees 341 8 3 19 Printing the Conflict Resolution Strategy printconfresolutionstrategy 342 8 3 20 Updating the Conflict Resolution Strategy updateconfresolutionstrategy 343 8 3 21 Setting the Master Definition Node setasmdn ceeeseeeeeeeeeeeeeeeeteees 344 8 3 22 Validating a Publication validatepub 00 0 0 cee eeeececeeneeeeeeeeceeeeeceteeeenaeees 345 8 3 23 Validating All Publications validatepubs cece eeeceeeeeeceeeeeeeeeeeeeseees 346 8 3 24 Removing a Publication reMOVEPUD ee eeeeeeeeneeceeeeeceeeeeceeeeecseeeeesaeees 347 8 3 25 Replicating DDL Changes replicatedd eee ceeeceeeeeeeceeeeeeeeeeeeeeeeeeeseees 348 8 3 26 Adding a Subscription Database addsubdb e ce eeeseeeeeneeeeeeeeeeeeeeeeeees 349 8 3 27 Printing Subscription Database IDs printsubdbids eee eeeeeeeeeeeeeeeeee 351 8 3 28 Printing Subscription Database Details printsubdbidsdetails 351 8 3 29 Updating a Subscription Database updatesubdb ee
308. o do this the publication database user must have the privilege to execute the ALTER TABLE statement on the publication tables and the publication database user must have CREATE and USAGE privileges on the schema containing the publication tables Verify that one of the following is true 1 All the tables in the publication are owned by the publication database user and the user has CREATE and USAGE privileges on the publication tables schemas or 2 the publication database user is a superuser Publication cannot be updated Reason The parent table schema table name is selected for removal while it has one or more child tables in the publication list Make sure that parent child dependency holds in the publication tables Resolution Choose the child tables for removal as well as the parent table Publication does not exist on the publication server It might have been removed Resolution The publication does not exist for a given subscription The subscription is no longer usable and must be removed Publication having subscription against it cannot be updated by adding tables into or removing tables from it Resolution Remove the subscription add tables to or remove tables from the publication then add the subscription Publication Service connection failure Resolution Verify that the publication server is running See Section 9 2 4 1 The replication control database cannot be re
309. o effect by overriding their defaults in the configuration files are logged in the publication server log file and the subscription server log file Section 3 2 contains the directory locations of these log files The following is a description of how to set the configuration options This is followed by sections describing the purpose of each option Step 1 The publication and subscription server configuration files are created during xDB Replication Server installation and already contain all of the configuration options as comments with their default settings To change the setting of a configuration option edit the publication server or subscription server configuration file by removing the comment symbol from the option and substituting the desired value in place of the currently coded value The following example shows a portion of the publication server configuration file where replacement of null characters in the publication data has been activated and the replacement character has been set to the question mark character replaceNullChar true Null Replacement Character nullReplacementChar Step 2 Restart the publication or subscription server Copyright 2012 EnterpriseDB Corporation All rights reserved 396 Postgres Plus xDB Replication Server with Multi Master User s Guide S su enterprisedb Password etc init d edb xdbpubserver restart Publication Service stopped Password Publication Service star
310. o install xDB Replication Server Step 2 Follow the prerequisite steps given in Section 5 1 for single master replication systems or Section 6 1 for multi master replication systems Step 3 Set the Java Runtime Environment as described by the following discussion On the host from which you intend to run the xDB Replication Server CLI the Java Runtime Environment JRE must be present and the Java runtime bin directory must be Copyright 2012 EnterpriseDB Corporation All rights reserved 313 Postgres Plus xDB Replication Server with Multi Master User s Guide included in the path of the operating system user name that will be used to run xDB Replication Server CLI A Java Runtime Environment is provided with each installation of Advanced Server The Java Runtime Environment is located in directory POSTGRES_ INSTALL HOME jre so can you include POSTGRES_ INSTALL HOME jre bin in your path For example on Linux systems enter the following on the command line or add it to your profile export PATH opt PostgresPlus 9 1AS jre bin PATH On Windows systems open the Properties dialog box of My Computer choose Advanced System Settings and then click on Environment Variables Edit the Path system environment variable to include the Java Runtime Environment bin directory Alternatively you can set the path for just the current session when you open the Command Prompt window as in the following example SET Path C Program Files Po
311. o the xDB Replication Console The steps for creating a replication system using the xDB Replication Server CLI are no different than those required when using the xDB Replication Console The logical components of the replication system must be created in the same order with the same sets of attributes as when creating the replication system with the xDB Replication Console You should understand the concepts and steps presented in chapters 2 and 5 for single master replication or 6 for multi master replication before building a replication system using the xDB Replication Server CLI There are no restrictions on using both the xDB Replication Console and the xDB Replication Server CLI to build and manage the same replication system In this chapter the syntax and examples are given for each xDB Replication Server CLI command Where applicable the discussion of a command contains a reference back to its xDB Replication Console counterpart where a detailed description of the affected component and its attributes can be found 8 1 Prerequisite Steps This section describes the installation and setup required prior to using the xDB Replication Server CLI The xDB Replication Server CLI is included if the xDB Replication Console component is chosen when installing xDB Replication Server The xDB Replication Server CLI is a Java application found in directory XDB_HOME bin Step 1 Follow the installation steps given in Chapter 3 t
312. oading data into target tables The default process is that the tables are loaded first and then the constraints are enabled afterwards Activate this option if there are triggers that affect how data is loaded into the target tables If there are target tables created as sets of Postgres inherited tables resulting from partitioned Oracle source tables then this option must be enabled enableConstBeforeDataLoad true false The default value is false 9 3 1 6 Assigning an IP Address for Remote Method Invocation Note The option described in this section applies to the publication server and the subscription server For Linux only An alternative method to modifying the etc hosts file so that the host name is associated with a non loopback IP address as discussed in Section 5 1 4 2 is to specify the network IP address using the java rmi server hostname option In the publication server configuration file set this option to the network IP address of the host running the publication server In the subscription server configuration file set this option to the network IP address of the host running the subscription server jJava rmi server hostname xxx XXX XX XXX Copyright 2012 EnterpriseDB Corporation All rights reserved 401 Postgres Plus xDB Replication Server with Multi Master User s Guide For example instead of modifying the etc hosts file to look like the following for a publication or subscription server run
313. oint value is not implicitly convertible to an INTEGER data type The following restrictions apply in order to use replication on tables with the SQL VARIANT data type e The values stored within the SQL VARIANT columns of the table to be replicated must be implicitly convertible to the same data type in Postgres e If there is more than one table with SQL VARIANT columns to be replicated to the same Postgres database then all such SQL VARIANT columns must contain values that are implicitly convertible to the same data type in Postgres In the Postgres subscription database you define a domain named sql_ variant that maps to an underlying data type to which all values in the SQL VARIANT columns are implicitly convertible The following example shows how to set up replication for a table containing a SQL VARIANT data type used to store numeric values but of different data types Copyright 2012 EnterpriseDB Corporation All rights reserved 408 Postgres Plus xDB Replication Server with Multi Master User s Guide The SQL Server table definition is the following CREATE TABLE variant _tbl Fal INTEGER PRIMARY KEY 2 SQL VARIANT INSERT INTO var ane tbl VALUES 1 CAST 1423 23 AS NUMERIC 6 2 INSERT INTO variant tbl VALUES 2 CAST 8001 AS INTEGER INSERT INTO variant tbl VALUES 3 CAST 4321 AS CHAR 4 GO
314. olution Note The conflict history can be viewed from the Publication node under any master node in the multi master replication system The history shows conflicts on all publication tables of all master nodes that occurred during synchronization and hence the history appears the same regardless of the master node under which it is viewed The following steps describe how to view the conflict history Step 1 Select any Publication node under a Database node representing a master node Tabs labeled General Realtime Monitor Replication History and Conflict History appear Publication Subscription Help UBwy Goa ta Replication Servers GS Publication Server 192 168 10 102 9051 E SMR E A MMR amp R Postgres Plus Advanced Server 1 E g emp_pub edb dept ft edb emp amp Postgres Plus Advanced Server 1 ag edb dept H E edb emp Publication schema edb Table count Figure 131 Selecting a publication on which to view conflict history Step 2 Click the Conflict History tab to show conflict history Click the Refresh button to ensure all conflicts are listed Copyright 2012 EnterpriseDB Corporation All rights reserved 210 Postgres Plus xDB Replication Server with Multi Master User s Guide Figure 132 Conflict History tab Step 3 Use the Conflict Display Criteria drop down list to display only conflicts of the chosen status a 2 9 Ee E edb de
315. on FATAL no pg_hba conf entry for host xxx xxx xxX xXxx user user name database db name SSL off Copyright 2012 EnterpriseDB Corporation All rights reserved 379 Postgres Plus xDB Replication Server with Multi Master User s Guide Error Messages and Resolutions Resolution Occurs when creating a subscription The subscription server running on host xxx xxx xx xxx Could not access the publication database Verify that the pg_hba conf file on the publication database server permits access from the subscription server host Unable to create subscription schema tables The database type is not supported Resolution The subscription database type is not supported for the intended publication database type See Section 9 1 2 for a list of permitted source and target database server configurations Unable to create subscription schema tables The table table name could not be created in EnterpriseDB database Resolution The subscription server was unable to create a subscription table definition in the intended target schema The error returned by the database server is displayed Typically the reason is that a table with the same name already exists in the target schema of the subscription database Unable to perform snapshot for subscription sub_name Reason org postgresql util PSQLException FATAL no pg hba conf entry for host XXX XXX XX XXX user user name database db name SSL off Resolution Occ
316. on From Oracle to PostgreSQL From Oracle to Postgres Plus Advanced Server From SQL Server to PostgreSQL From SQL Server to Postgres Plus Advanced Server From Postgres Plus Advanced Server to Oracle From PostgreSQL to SQL Server From Postgres Plus Advanced Server to SQL Server Between PostgreSQL and Postgres Plus Advanced Server For multi master replication xDB Replication Server supports the following configurations e Between PostgreSQL database servers e Between PostgreSQL database servers and Postgres Plus Advanced Servers in PostgreSQL compatible mode e Between Postgres Plus Advanced Servers in PostgreSQL compatible mode e Between Postgres Plus Advanced Servers in Oracle compatible mode Note See Section 9 1 for detailed information on supported source and target database server configurations Copyright 2012 EnterpriseDB Corporation All rights reserved 9 Postgres Plus xDB Replication Server with Multi Master User s Guide The reader is assumed to have basic SQL knowledge and basic Oracle SQL Server or PostgreSQL database administration skills whichever are applicable so that databases users schemas and tables can be created and database object privileges assigned This document is organized as follows e The remainder of Chapter 1 describes conventions used throughout this user s guide along with suggested sections to read based upon your purpose for using this guide e Chapter 2 provides an overview of
317. on 3 1 e User Name Database superuser name that the publication server uses to connect to the xDB Control database This is the user name you specified on the Postgres Installation Details screen in Step 15 of Section 3 1 e Password Password of the database superuser given in the User Name field e Save login information Check this box if you do not want to re register the publication server each time you open the xDB Replication Console See Section 4 2 for additional information on the advantages and disadvantages of saving server login information Note The user name and password combination you enter is authenticated against the user name and password in the xDB Replication Configuration file residing on the host with the IP address you enter in the Host field Copyright 2012 EnterpriseDB Corporation All rights reserved 119 Postgres Plus xDB Replication Server with Multi Master User s Guide a Register Publication Server gt Host 192 168 2 7 Port 9051 UserName enterprisedb Password Save login information Figure 65 Register Publication Server dialog box Click the Register button after you have filled in the fields A Publication Server node appears in the replication tree of the xDB Replication Console Expand the Publication Server node to expose the SMR and MMR type nodes g Replication Servers General Publication Databases Publication Server 192 168 2 7 905
318. on 7 4 1 or it can be run on demand The following are the steps to run shadow table history cleanup on demand for a chosen publication Step 1 Make sure the publication server whose node is the parent of the publication whose shadow table history you wish to clean up is running and has been registered in the XDB Replication Console you are using See Section 5 2 1 for directions on starting and registering a publication server Step 2 Select the Publication node of the publication for which you want to clean up the shadow table history File Publication Subscription Help General Realtime Monitor Replication H Property Publication schema Table count Subscription count QW Oracle 192 168 2 6 1521 xe pubut 5 g sales_dept Ea EDB DEPT EDB EMP Fs Subscription Server 192 168 2 7 9052 Figure 173 Selecting a publication for shadow table history cleanup Step 3 From the Publication menu choose Cleanup Shadow Table History Alternatively click the secondary mouse button on the Publication node and choose Cleanup Shadow Table History The Cleanup Synchronization History confirmation box appears Copyright 2012 EnterpriseDB Corporation All rights reserved 248 Postgres Plus xDB Replication Server with Multi Master User s Guide GH Publication Server 192 168 2 7 9051 a MMR S P sur GQ Oracle 192 168 2 6 1521 xe pubu B SELER EJ EDB E enel Figure 174 Cleaning up shado
319. on Server 192 168 2 7 9051 2 MMR amp B3 SMR al Oracle 192 168 2 6 1521 xe pubus Sy sales_dept H E Subscription Server 192 168 2 7 9052 Figure 169 Selecting the publication database for cleanup scheduling Step 3 From the Publication menu choose Preferences Alternatively click the secondary mouse button on the Publication Database node and choose Preferences The Publication Server Preferences dialog box appears Copyright 2012 EnterpriseDB Corporation All rights reserved 244 Postgres Plus xDB Replication Server with Multi Master User s Guide Figure 170 Publication Server Preferences dialog box Step 4 In the Publication Server Preferences dialog box uncheck the box if you do not want to run a scheduled shadow table history cleanup job Click the OK button and skip the remaining steps Copyright 2012 EnterpriseDB Corporation All rights reserved 245 Postgres Plus xDB Replication Server with Multi Master User s Guide Cleanup Job The synchronization history is maintained in the shadow tables by default You can schedule a cleanup job that will remove the synchronized transactions history from shadow tables on periodic basis Run Cleanup Job After Every ot Every Day at 01 Every Is inday Figure 171 Disabled schedule for shadow table history cleanup Step 5 If you want to schedule shadow table history cleanup make su
320. on Server read sections 2 1 2 2 and 2 3 If you are planning on implementing a replication system using xDB Replication Server read sections 2 1 2 2 2 3 and 2 4 If you are ready to install configure and begin using xDB Replication Server for single master replication read chapters 3 4 5 and 7 Copyright 2012 EnterpriseDB Corporation All rights reserved 11 Postgres Plus xDB Replication Server with Multi Master User s Guide e If you are ready to install configure and begin using xDB Replication Server for multi master replication read chapters 3 4 6 and 7 e If you need help finding a solution to a problem see Section 9 2 Copyright 2012 EnterpriseDB Corporation All rights reserved 12 Postgres Plus xDB Replication Server with Multi Master User s Guide 2 Overview This chapter defines basic replication terms and concepts and presents an overview of the components and architecture of xDB Replication Server The chapter concludes with design guidelines and directions for implementing a replication system using xDB Replication Server 2 1 Why Use Replication Replication of data can be employed in a variety of use cases in organizations where it is important to use the same data in multiple settings This allows users to work with real data that will yield real results that are reliable in more than one setting Support of both single master and multi master replication gives xDB Replication Serv
321. on Server with Multi Master User s Guide td Replication Servers Publication Server 192 168 2 7 9051 S Subscription Server 192 168 2 7 9052 ae Postgres Plus Advanced Server 192 1 Figure 108 Selecting a subscription database definition for removal Step 3 From the Subscription menu choose Subscription Database then Remove Database Alternatively click the secondary mouse button on the Subscription Database node and choose Remove Subscription The Remove Subscription Database confirmation box appears Step 4 In the Remove Subscription Database confirmation box click the Yes button Copyright 2012 EnterpriseDB Corporation All rights reserved 161 Postgres Plus xDB Replication Server with Multi Master User s Guide Publication Server 192 168 2 7 9051 Subscription Server 192 192 168 2 7 15444 subb subuser Figure 109 Remove Subscription Database confirmation The Subscription Database node no longer appears under the Subscription Server node tq Replication Servers G Publication Server 192 168 2 7 9051 cription Server 19 Figure 110 Replication tree after removal of a subscription database Copyright 2012 EnterpriseDB Corporation All rights reserved 162 Postgres Plus xDB Replication Server with Multi Master User s Guide 5 6 Performing Controlled Switchover Controlled switchover is the exchanging of roles between a publication database and a subscription data
322. on and subscription server registration process Enter values for the following fields e Host Network address of the Postgres database server that is to host the xDB Control database Localhost is acceptable if the xDB Control database is to reside on the same machine where you are running this installation process e Port Port number on which the Postgres database server is listening for connections e User Name The database superuser name to authenticate connections to the xDB Control database by the publication server or subscription server running on this host You must also use this superuser name and password when you register a publication server or a subscription server running on this host Default superuser Copyright 2012 EnterpriseDB Corporation All rights reserved 78 Postgres Plus xDB Replication Server with Multi Master User s Guide is postgres enterprisedb for Advanced Server installed in Oracle compatible configuration mode e Password Password of the database user given in the User Name field e Control Database The database name of the xDB Control database If the database does not already exist it will be created Default database name is postgres edb for Advanced Server installed in Oracle compatible configuration mode Postgres Plus Installation Details Please verify the Postgres Plus installation details Host localhost s s s Port aaa l Password reer Control Database
323. on shown in the dialog box make sure the network location shown in the dialog box is correct Re enter the user name and password saved in the xDB Replication Configuration file that resides on the host identified by the IP address in the Host field Check the Save Login Information box Copyright 2012 EnterpriseDB Corporation All rights reserved 258 Postgres Plus xDB Replication Server with Multi Master User s Guide Host 192 168 2 8 Port 9051 User Name enterprisedb Password 6ee0e060 V Save login information Update l Cancel Figure 185 Updated publication server location Step 4 Click the Update button If the dialog box closes then the update to the server login file was successful Click the Refresh icon in the xDB Replication Console tool bar to show the updated Publication Server node If an error message appears after clicking the Update button the server login file is not modified Investigate and correct the cause of the error Repeat steps 1 through 4 7 5 1 2 Subscription Server Network Location Note This section applies only to single master replication systems Part of the metadata stored for each publication server is the network location of subscription servers that manage subscriptions associated with the publication server s publications This network information enables the publication server to communicate with the subscription server If the netwo
324. onding to an update transaction on the source node is not found on the target node as the row has already been deleted on the target node This is referred to as an update delete conflict Conversely if there is a delete transaction on the source node and an update transaction for the same row on the target node this case is referred to as a delete update conflict Finally in the case where the row corresponding to a delete transaction on the source node is not found on the target node as the row has already been deleted on the target node is referred to as a delete delete conflict The following table definition is used to illustrate conflict resolution examples CREATE TABLE addrbook id SERIAL PRIMARY KEY name VARCHAR 20 address VARCHAR 50 i The following table illustrates an example of a uniqueness conflict Table 2 Uniqueness Conflict Timestamp Master Node A Master Node B INode A INSERT INTO address DDR A INTO addrbook name address UES B ADDR B a a 4 id name A 2 ERT INTO ADDR A id 1 name C name address iq name B address ADDR C ES C ADDR C annie as p Row change for INSERT tx id 1 on Node A results in unique key conflict on Node Synchronization pushes Node A B changes to Node B id 1 name c ADDR C 1 name A address ADDR A The following table illustrates an e
325. ontrol database Over time the size of Copyright 2012 EnterpriseDB Corporation All rights reserved 237 Postgres Plus xDB Replication Server with Multi Master User s Guide the replication history tables will grow Replication history records can be periodically deleted See Section 7 4 3 for information on cleaning up replication history 7 3 2 Hiding Synchronizations With Zero Transaction Counts You may notice synchronization replications with transaction counts of zero These records indicate that there were no changes to synchronize at the time the replication occurred For scheduled replications that occur frequently this may result in a large number of lines in the Replication History tab thus obscuring the more meaningful replications with non zero transaction counts as shown below General Realtime Monitor Replication History 2012 06 07 11 28 28 Success 0 071 Secs 0 Synchronize 2012 06 07 11 28 08 Success 0 0090 Secs 0 Synchronize 2012 06 07 11 27 43 Success 0 011 Secs 0 Synchronize 2012 06 07 11 27 28 Success 0 0080 Secs 0 Synchronize 2012 06 07 11 27 08 Success 0 061 Secs 1 Synchronize 2012 06 07 11 26 48 Success 0 0070 Secs 0 Synchronize 2012 06 07 11 26 28 Success 0 0070 Secs 0 Synchronize 2012 06 07 11 26 08 Success 0 0080 Secs 0 Synchronize 2012 06 07 11 25 48 Success 0 0070 Secs 0 Synchronize 2012 06 07 11 25 28 Success 0 013 Secs 0 Synchronize 2012 06 07 11 25 08 Success 0 01 Secs 0 Synchronize 2012 06 07 11 24 4
326. or Postgres Plus Advanced Server for the type of subscription database For an Advanced Server Oracle compatible installation select the Postgres Plus Advanced Server option For an Advanced Server PostgreSQL compatible installation select the PostgreSQL option e Host IP address of the host on which the subscription database server is running e Port Port on which the subscription database server is listening for connections e User The subscription database user name chosen in Section 5 1 3 1 for a Postgres subscription database or the database user name created in Step 2 of Section 5 1 3 2 for an Oracle subscription database or the database user name created in Step 2 of Section 5 1 3 3 for a SQL Server subscription database e Password Password of the database user e Service ID For Oracle Enter the Oracle System Identifier SID of the Oracle instance running the subscription database if the SID radio button is selected Enter the net service name of a connect descriptor as defined in the TNSNAMES ORA file if the Service Name radio button is selected e Database For Postgres or SQL Server Enter the Postgres or SQL Server database name Database Type Postgres Plus Advanced Server v r Postgres Plus Advanced Server Database Information G Please specify Postgres Plus Advanced Server database information Host 192 168 2 7 Port 5444 User subuser Password 0000000e Datab
327. oration All rights reserved 260 Postgres Plus xDB Replication Server with Multi Master User s Guide D HostiP Figure 187 Update Subscription Servers dialog box Step 3 Enter the new network location for each subscription server in the list whose network location has changed Copyright 2012 EnterpriseDB Corporation All rights reserved 261 Postgres Plus xDB Replication Server with Multi Master User s Guide e 192 168 2 8 Figure 188 Updated subscription server location Step 4 Click the Update button If the dialog box closes then the update to the publication server s metadata was successful If an error message appears investigate and correct the cause of the error Repeat steps 1 through 4 Step 5 If the subscription server with the new network location manages subscriptions associated with publications in other publication servers repeat steps 1 through 4 for these other publication servers 7 5 2 Updating a Publication Database When you create a publication database definition you save the publication database server s network location IP address and port number the database identifier a database login user name and the user s password in the xDB Control database used by the publication server This login information is used whenever a session needs to be established with the publication database See Section 5 2 2 for information on creating a publication database definition for a sin
328. ore of these steps is a common source of errors Step 1 Verify that the database server of the publication database the database server of the subscription database for single master replication systems the database servers of the master nodes for multi master replication systems and the database server of the xDB Control database are all running Copyright 2012 EnterpriseDB Corporation All rights reserved 382 Postgres Plus xDB Replication Server with Multi Master User s Guide Step 2 When viewing information in the xDB Replication Console click the Refresh icon in the toolbar to ensure you are viewing the most current information especially after making a configuration change to your replication system Step 3 Verify that the publication server and the subscription server for single master replication systems are running If they are not running and cannot be started see Section 9 2 4 1 Step 4 If you are using an Oracle publication or subscription database verify that the Oracle JDBC driver file ojdbc14 jar has been copied to the XDB_HOME 1ib jdbc directory XDB_ HOME is the location where you installed xDB Replication Server This directory is typically the Postgres installation home directory See Section 5 1 1 1 Step 5 Verify that the necessary privileges have been granted to the publication database user For an Oracle publication database verify that the publication database user has CONNECT RESOURCE and
329. ork location user name and password e A subscription database definition is created subordinate to the subscription server The Oracle database user name subuser is specified in the definition along with the database network location and database identifier e A subscription named sub is created subordinate to the subscription database definition When you create a user named subuser in Oracle a schema named subuser is automatically created by Oracle at the same time The table definitions for tables A B and C are created in schema subuser when you create subscription sub When replication occurs the publication server populates these tables with rows from the publication The following screen capture shows how the logical components of this replication system appear in the xDB Replication Console replication tree File Publication SOR a G Publication Server 192 168 2 3 9051 SBS SMR R Postgres Plus Advanced Server 192 168 2 3 5444 pubdb pubuser Ej ty pub EE s1 a H s2 b H E s2 c hod MMR 6 Subscription Server 192 168 2 3 9052 S A o Oracle 192 163 2 3 1521 xe subuser sub ty pub sia H E s2 b H E s2 c Figure 16 Postgres Plus Advanced Server to Oracle replication tree Copyright 2012 EnterpriseDB Corporation All rights reserved 44 Postgres Plus xDB Replication Server with Multi Master User s Guide See Chapter 4 for an introduction to the xDB Replication Console 2 3 3 4 PostgreSQL or Advanced
330. orporation All rights reserved 230 Postgres Plus xDB Replication Server with Multi Master User s Guide Step 5 In the Scheduled Task Wizard dialog box create the new schedule See Step 3 of Section 7 1 for details on how to create a new schedule Scheduled Task Wizard r Schedule Category Type of Task Synchronize C Snapshot Perform this task Continuously C Daily C Weekly Monthly C Cron Expression Bac next gt Cancel Figure 155 Scheduled Task Wizard dialog box 7 2 2 Removing a Schedule If you no longer wish replication to take place automatically you must remove the schedule You can always re add a schedule or perform on demand replication Step 1 For SMR only Make sure the subscription server whose node is the parent of the subscription you wish to change is running and has been registered in the xDB Replication Console you are using See Section 5 3 1 for directions on starting and registering a subscription server Step 1 For MMR only Make sure the publication server whose node is the parent of the master definition node you wish to change is running and has been registered in the xDB Replication Console you are using See Section 5 2 1 for directions on starting and registering a publication server Step 2 For SMR only Select the Subscription node of the subscription for which you wish to remove the schedule Copyright 2012 EnterpriseDB
331. ot check this box it is assumed that you have already created the table definitions in the master node e Perform Initial Snapshot Check this box if you want the publication server to perform a snapshot from the master definition node to this master node when you click the Save button If you do not check this box the tables on the master node will not be loaded until you perform a replication at some later time Copyright 2012 EnterpriseDB Corporation All rights reserved 191 Postgres Plus xDB Replication Server with Multi Master User s Guide r Postgres Plus Advanced Server Database Information G Please specify Postgres Plus Advanced Server database information Host 192 168 10 103 User mmruser Database mmrnode Node Priority Level 2 V Replicate Publication Schema _ Perform initial Snapshot Test Save Cancel Figure 119 Publication Service Add Database dialog box for an additional master node Step 4 Click the Test button If Test Result Success appears click the OK button then click the Save button Copyright 2012 EnterpriseDB Corporation All rights reserved 192 Postgres Plus xDB Replication Server with Multi Master User s Guide Figure 120 Successful master node test If an error message appears investigate the cause sof the error correct the problem and repeat steps 1 Brough 4 When the publication database definition is succe
332. ove all master nodes and the master definition node using the xDB Replication Console or xDB Replication Server CLI schema edb replicator pub and all of its database objects are deleted from the xDB Control database 6 5 On Demand Replication After a master definition node its publication and additional master nodes are created there are a couple of choices for starting the replication process e Replication can be done immediately by performing an on demand snapshot or synchronization replication e Replication can be scheduled to start at a later date and time by creating a schedule This section discusses the procedure for initiating a replication on demand Section 7 1 discusses how to create a schedule 6 5 1 Performing Snapshot Replication A snapshot replication occurs from the master definition node to a selected master node When you create a master node for the first time you have the option of performing an initial snapshot see Step 3 of Section 6 3 You can perform snapshots to this master node at any later point in time according to the following steps Step 1 Select the Publication node under the master node for which you wish to perform snapshot replication Copyright 2012 EnterpriseDB Corporation All rights reserved 196 Postgres Plus xDB Replication Server with Multi Master User s Guide sq Replication Servers E Publication Server 192 168 10 102 9051 8 sur A MMR GR postgres
333. oving publication s replication history Copyright 2012 EnterpriseDB Corporation All rights reserved 372 Postgres Plus xDB Replication Server with Multi Master User s Guide Replication history has been removed 8 3 44 Cleaning Up All Replication History cleanrephistory The cleanrephistory command deletes the replication history for all publications in the specified publication server Synopsis cleanrephistory repsvrfile pubsvrfile See Section 7 4 3 for additional information on cleaning up replication history Parameters pubsvrfile The file containing the publication server login information Examples In the following example replication history is deleted for all publications in the publication server identified by the content of file pubsvrfile prop java jar edb repcli jar cleanrephistory repsvrfile pubsvrfile prop Removing all publication s replication history Replication history has been removed Copyright 2012 EnterpriseDB Corporation All rights reserved 373 Postgres Plus xDB Replication Server with Multi Master User s Guide 9 Appendix This chapter discusses various miscellaneous topics 9 1 Source and Target Database Server Configurations Depending upon the database products you are using with xDB Replication Server Oracle SQL Server PostgreSQL or Postgres Plus Advanced Server along with the compatibility configuration mode if you are using Advanced Server certain combi
334. pear on the Replication History tab as zero transaction count replications occur 7 3 3 Shadow Table History Expanding the nodes under the Subscription node of a single master replication system or the Publication node of a multi master replication system provides more information about the subscription or publication Step 1 Select a table to reveal tabs that contain general information about the table and the replication history of the table Expand a Table node to reveal the columns in the table File Publication Subscription Help 6 S8uy OSS a General Realtime Monitor Replication History g Replication Servers Hh Publication Server 192 168 2 7 9051 J subscription Server 192 168 2 7 9052 Property ie P Postgres Plus Advanced Server 192 1 Name EMP sales_dept_sub Schema EDB amp ty sales_dept PK attributes EMPNO EDB DEPT Attributes count 8 amp Filter Clause deptno 30 EMPNO AB ENAME AB JOB EJ mer RE HIREDATE EJ sat i COMM DEPTNO Figure 166 Table properties and columns Step 2 Click the Replication History tab to show a history of replications for this table Copyright 2012 EnterpriseDB Corporation All rights reserved 240 Postgres Plus xDB Replication Server with Multi Master User s Guide General Realtime Monitor Replication History 2012 06 07 11 49 04 Success 3 Synchronize View data 2012 06 07 11 47 08 Success 8 Snapshot Fi
335. pears under the Publication Database node a Replication Servers oe Publication Server 192 168 2 7 9051 23 SMR ol Oracle 192 168 2 6 1521 xe pubu ef MMR tg Subscription Server 192 168 2 7 9052 i Postgres Plus Advanced Server 192 Figure 223 Replication tree after removing a publication Copyright 2012 EnterpriseDB Corporation All rights reserved 298 Postgres Plus xDB Replication Server with Multi Master User s Guide 7 5 6 Removing a Publication Database Deleting a publication database definition from xDB Replication Server is equivalent to removing its Publication Database node In a single master replication system before a Publication Database node can be removed all publications under that Publication Database node must be removed See Section 7 5 5 for directions on removing a publication In a multi master replication system removing a Publication Database node representing a master node other than the master definition node eliminates that node s future participation in the replication system Synchronization replications no longer involve tables in the removed master node In a multi master replication system removing the Publication Database node representing the master definition node removes the remaining metadata database objects of that particular multi master replication system effectively removing the multi master replication system except for the database objects comprising the public
336. plication Server CLI Figure 8 xDB Replication Server physical view single master replication system The following diagram illustrates the components of xDB Replication Server and how they are used to form a complete basic multi master replication system Copyright 2012 EnterpriseDB Corporation All rights reserved 25 Postgres Plus xDB Replication Server with Multi Master User s Guide replication system xDB Replication Console or xDB Replication Server CLI xDB Replication Server xDB Figure 9 xDB Replication Server physical view multi master replication system The minimal configuration of xDB Replication Server for a basic replication system consists of the following software components e Publication server The program that configures the publication database and master nodes for replication and performs replication e Subscription server The program that configures the subscription database for replication and initiates replication The subscription server is used only in single master replication systems e xDB Control database The Postgres database containing the metadata of the replication system e xDB Replication Configuration file Text file containing connection and authentication information used by the publication server and subscription server upon startup to connect to the xDB Control database Also used to authenticate registration of the publication server and subscription server from the u
337. plication system and a multi master replication system 2 2 2 Publications and Subscriptions XDB Replication Server uses an architecture called publish and subscribe The data to be made available for copying by a replication system is defined as a publication To get a copy of that data you must subscribe to that publication The manner in which you subscribe is slightly different for single master and multi master replication systems Copyright 2012 EnterpriseDB Corporation All rights reserved 15 Postgres Plus xDB Replication Server with Multi Master User s Guide In xDB Replication Server a publication is defined as a named set of tables and views within a database The database that contains the publication is called the publication database of that publication In a single master replication system to get a copy of an xDB Replication Server publication you must create a subscription An xDB Replication Server subscription is a named association of a publication to a database to which the publication is to be copied This database is called the subscription database Similar to a single master replication system when creating a multi master replication system you first define a publication in the publication database You then add one or more additional databases that you want to participate in this multi master replication system As you add each database it is associated with this replication system You do not create an
338. ply as values for the tables parameter are case sensitive Unless quoted identifiers were used to build the database objects Oracle names must be entered using uppercase letters for example EDB DEPT and Advanced Server names must be entered in lowercase letters for example edb dept See Section 9 3 5 for additional information on quoted identifiers and case translation Parameters pubname The name of the publication from which tables or views are to be removed pubsvrfile The file containing the publication server login information schema tn The name of the schema containing the nth table of the tables parameter list This value is case sensitive table n The name of the nth table in the tables parameter list This value is case sensitive schema vn The name of the schema containing the nth view of the tables parameter list This value is case sensitive Copyright 2012 EnterpriseDB Corporation All rights reserved 337 Postgres Plus xDB Replication Server with Multi Master User s Guide view n The name of the nth view in the tables parameter list This value is case sensitive Examples In the following example table edb jobhist and view edb salesemp are removed from the analysts_managers publication java jar edb repcli jar removetablesfrompub analysts managers gt repsvrfile pubsvrfile prop gt tables edb jobhist edb salesemp Removing tables from publication analysts mana
339. pt edb dept 192 168 10 192 168 10 _ EE edb emp Figure 133 Selecting conflict history by status Step 4 Click the View Data link to show the details of a particular conflict Copyright 2012 EnterpriseDB Corporation All rights reserved 211 Postgres Plus xDB Replication Server with Multi Master User s Guide redb emp Database Origin empno ename job mor hiredate sal Source DB 2001 SALESMAN 7900 9500 00 3 Target DB 9001 ANALYST 7900 5000 00 Figure 134 Conflict Details window 6 8 Updating the Conflict Resolution Options A current conflict resolution option on a publication table can be changed See Section 6 6 for information on conflict resolution Step 1 Make sure the publication server whose node is the parent of the publication you wish to change is running and has been registered in the xDB Replication Console you are using See Section 5 2 1 for directions on starting and registering a publication server Step 2 Select the Publication node under the Publication Database node representing the master definition node Copyright 2012 EnterpriseDB Corporation All rights reserved 212 Postgres Plus xDB Replication Server with Multi Master User s Guide Replication Servers GA Publication Server 192 168 10 102 9051 gt a SMR 2 MMR GP postgres Plus Advanced Server 1 3g H E edb dept EE edb emp GR Postgres Plus Advanced Server 19
340. ption database and master nodes may all run on the same host each component may run on its own separate host or any combination of components may run on any number of hosts However for practical purposes there are two basic scenarios The simplest case is where all components are on the same host The other case is where you have the Oracle Copyright 2012 EnterpriseDB Corporation All rights reserved 58 Postgres Plus xDB Replication Server with Multi Master User s Guide or SQL Server database server running on a host separate from the rest of the replication system components This section discusses the advantages and disadvantages of each scenario 2 4 5 1 Single Host The simplest implementation of a replication system is when all replication components run on a single host This means that the PostgreSQL or Advanced Server installation the complete xDB Replication Server installation publication server subscription server and xDB Control database and the Oracle or SQL Server database server reside on the same machine The Postgres publication or subscription database as the case may be can reside in the initial database cluster that is created when Postgres is installed on the host ost with Oracle server and Postgres Plus server xDB Replication Console or xDB Replication Server CLI Server Figure 21 Single host replication system Copyright 2012 EnterpriseDB Corporation All rights reserved 59 Pos
341. publication is created the publication server creates database objects in the xDB Control database and in the publication database to record metadata about the publication Whenever a master node is added to a multi master replication system the publication server creates database objects in the master node for recording metadata For master nodes other than the master definition node the publication server also calls EnterpriseDB s Migration Toolkit to create the publication table definitions if so chosen at master node creation time The publication server is also responsible for performing a replication For snapshot replications the publication server calls EnterpriseDB s Migration Toolkit to perform the snapshot For single master synchronization replications the publication server uses the Java Database Connectivity JDBC interface to apply changes to the subscription table rows based on changes that have been recorded in metadata tables in the publication database For multi master synchronization replications the publication server performs the same process as for single master synchronizations but does so for each master node pair combination in the multi master replication system Copyright 2012 EnterpriseDB Corporation All rights reserved 27 Postgres Plus xDB Replication Server with Multi Master User s Guide The publication server may run on the same host as the other xDB Replication Server components or it may r
342. publication must be created in the master definition node before creating additional master nodes See Section 8 3 11 for the command to create a publication java jar edb repcli jar addpubdb repsvrfile pubsvrfile prop gt dbtype enterprisedb dbhost 192 168 2 7 dbport 5444 gt dbuser mmruser dbpassword ygJ9AxoJEX854elcVIJPTw gt gt database mmrnode repgrouptype m Copyright 2012 EnterpriseDB Corporation All rights reserved 324 Postgres Plus xDB Replication Server with Multi Master User s Guide gt nodepriority 3 Adding Publication Database Replicating publication schema Publication database added successfully Publication Database id 9 8 3 6 Printing Publication Database IDs printpubdbids The printpubdbids command prints the publication database IDs of the publication database definitions Synopsis printpubdbids repsvrfile pubsvrfile Parameters pubsvrfile The file containing the publication server login information Examples The following example lists the publication database IDs of the publication database definitions S java jar edb repcli jar printpubdbids repsvrfile pubsvrfile prop Printing publication database ids 6 ERNI Wes 8 3 7 Printing Publication Database Details printpubdbidsdetails The printpubdbidsdetails command prints the connection information for each publication database definition Synopsis printpubdbidsdetails repsvrfile p
343. publication server login information for the publication server that manages the publication associated with subscription subname Note that the values that you supply for newpubsvr ipaddress and newpubsvc_ port must be the same as the values set in fields host and port in file pubsvrfile newpubsvr_ ipaddress The new IP address for the publication server that manages the publication associated with subscription subname This value must be the same as the IP address specified for field host in file pubsvrfile newpubsvr port The new port number for the publication server that manages the publication associated with subscription subname This value must be the same as the port number specified for field port in file pubsvrfile Examples If the publication server host IP address has been changed to 192 168 2 7 then make sure the publication server login information in file pubsvrfile prop contains the new IP address as shown by the following host 192 168 2 7 port 9051 user enterprisedb Password is in encrypted form password ygJ 9AxoJEX854elcVIJPTw To update the metadata for subscription dept _emp_sub so that its subscription server can find the new publication server host run the following command java jar edb repcli jar updatesub dept emp sub gt subsvrfile subsvrfile prop gt pubsvrfile pubsvrfile prop gt Jose OZ 168 227 N Copyright 2012 EnterpriseDB Corporation All rights reserved 368
344. pubsvrfile The file containing the publication server login information Examples The tables belonging to publication dept __emp are printed java jar edb repcli jar printpublishedtables dept_emp gt repsvrfile pubsvrfile prop primemo toblesiunderipublkhicacion deptiemnp EDB DEPT EDB EMP 8 3 14 Adding Tables to a Publication addtablesintopub The addtablesintopub command adds tables or views into an existing publication Copyright 2012 EnterpriseDB Corporation All rights reserved 334 Postgres Plus xDB Replication Server with Multi Master User s Guide Synopsis addtablesintopub pubname repsvrfile pubsvrfile tables schema_tl table_1 schema_t2 table 2 J views schema_vl view_1 schema v2 view 2 tablesfilterclause ordinal ti filter ti ordinal 222 fitter t2 J gsi viewsfilterclause ordinal vi filter_vi ordinal v2 filter v2 repgrouptype m s The addtablesintopub command updates an existing publication identified by pubname If the publication is snapshot only then any views listed after the views parameter are ignored See Section 7 5 3 1 for additional information on adding tables to a publication Note The schema names table names and view names that you supply as values for the tables and views parameters are case sensitive Unless quoted identifiers were used to build the database objects Oracle names must
345. quest for authentication information This allows an unauthorized person to perform any operation on the exposed publications and subscriptions including the potential to completely delete the replication system Note The publication database and subscription database cannot be deleted but unauthorized replications could be forced to occur Thus it is important that operating system accounts are secure on hosts that have access to an xDB Replication Console and a replication system Copyright 2012 EnterpriseDB Corporation All rights reserved 98 Postgres Plus xDB Replication Server with Multi Master User s Guide 5 Single Master Replication Operation This chapter describes how to configure and run xDB Replication Server for single master replication systems For configuration and management of your replication system the xDB Replication Console graphical user interface is used to illustrate the steps and examples in this chapter The same steps can be performed from the operating system command line using the xDB Replication Server Command Line Interface CLI The commands of the xDB Replication Server CLI utility are described in Chapter 8 5 1 Prerequisite Steps Certain steps must be taken to prepare the host environments as well as the publication and subscription database servers before beginning the process of building a single master replication system This section describes these steps 5 1 1 Enabling Access to th
346. r See Section 5 2 1 for more information on the purpose of these fields and the process of registering a publication server Copyright 2012 EnterpriseDB Corporation All rights reserved 96 Postgres Plus xDB Replication Server with Multi Master User s Guide The following shows the Register Subscription Server dialog box In this example 192 168 2 7 entered in the Host field 9052 entered in the Port field enterprisedb entered in the User Name field and an encrypted form of the password entered in the Password field are saved in the server login file for this subscription server if user name and password validation are successful Register Subscription Server eS Host 192 168 2 7 Port 9052 UserName enterprisedb Password eeeeeee Save login information Register Cancel Figure 61 Save login information option for a subscription server See Section 5 3 1 for more information on the purpose of these fields and the process of registering a subscription server Saving server login information gives you the convenience of immediate access to the publication server and any of its subordinate publications or access to the subscription server and any of its subordinate subscriptions That is when you open the xDB Replication Console the Publication Server nodes of saved publication servers immediately appear in the replication tree allowing you to perform administrative tasks o
347. r 7 gt DROP PROCEDURE pubuser CreateTxSet 8 gt DROP PROCEDURE pubuser CreateUniTxSet 9 gt DROP PROCEDURE pubuser GetNewTxsCount 10 gt DROP PROCEDURE pubuser JobCleanup 11 gt DROP PROCEDURE pubuser JobCreateTxSet 12 gt DROP PROCEDURE pubuser LoadPubTableList 13 gt DROP PROCEDURE pubuser nextval 14 gt DROP PROCEDURE pubuser RemoveCleanupJob 15 gt DROP PROCEDURE pubuser RemoveCreateTxSetJob 16 gt DROP PROCEDURE pubuser spl createsequence 17 gt DROP PROCEDURE pubuser sp dropsequence 18 gt GO lS 2 gt DROP TABLE pubuser rrep common_seq o DROP TABLE pubwsen wrnep lock 4 gt DROP TABLE pubuser rrep mmr pub group 5 gt DROP TABLE pubuser rrep mmr txset 6 gt DROP TABLE pubuser rrep properties 7 gt DROP TABLE pubuser rrep publication subscriptions 8 gt DROP TABLE pubuser rrep publication tables 97 DE ORLA Rasp ulus ers nism pm lels MO DROP TABLE jpubuser rrep ex Seg i gt DROP TABLE PUbUSer r repesett 12 DROP VVAB TE pUbUser ene pss ee mine allah 13 gt DROP TABLE pubUc erer repesett log i4 gt DROP TABLE pubuser rrep Exseu seq 15 gt DROP TABLE pubuser RRST edb dept 16 gt DROP TABLE pubuser RRST edb emp 17 gt GO For Postgres only If the schema edb replicator pub still exists in the publication database drop the schema and all of its database objects The following example shows a connection established in psq1 to the publication database edb The DROP SCHEMA CASCADE stat
348. r from the xDB Replication Console The messages are listed in alphabetical order based on the first word in the message following a an or the When an error message is displayed by the xDB Replication Console it may be followed by a specific reason as denoted by Reason reason for failure as in the following example Authentication failed Reason Invalid user name password The various specific reasons are not listed for all messages in the table Table 8 xDB Replication Server Error Messages Error Messages and Resolutions Authentication failed Reason Invalid user name password Resolution Occurs when registering a publication server or subscription server Verify the user name Copyright 2012 EnterpriseDB Corporation All rights reserved 375 Postgres Plus xDB Replication Server with Multi Master User s Guide Error Messages and Resolutions and password you enter matches the user name and password in the xDB Replication Configuration file on the host you are running the publication server or subscription server The connection could not be established with the server Verify that the server is running and accepting connections Resolution Occurs whenever a Java RMI connection cannot be made to the publication server the subscription server or a database server Can occur when registering a publication or subscription server adding a publication database or a subscription database or identifyi
349. r login information dbtype Specify oracle if the database is an Oracle database Specify enterprisedb if the database is an Advanced Server database in Oracle compatible configuration mode Specify postgresql if the database is a PostgreSQL database or an Advanced Server database in PostgreSQL compatible configuration mode Specify sqlserver if the database is a Microsoft SQL Server database Copyright 2012 EnterpriseDB Corporation All rights reserved 349 Postgres Plus xDB Replication Server with Multi Master User s Guide host The IP address of the host on which the subscription database server is running port The port number on which the database server is listening for connections user The subscription database user name encrypted pwd The encrypted password of the subscription database user See Section 8 3 4 for directions on using the encrypt command to generate an encrypted password pwdfile The file containing the encrypted password of the subscription database user oraconnectiontype Specify sid if the Oracle system ID SID is used to identify the subscription database in the database parameter Specify servicename if the Oracle service name is used to identify the subscription database in the database parameter dbname The Postgres or SQL Server database name the Oracle SID or the Oracle service name of the subscription database Examples The following example adds a subscription database definition
350. r login information Copyright 2012 EnterpriseDB Corporation All rights reserved 328 Postgres Plus xDB Replication Server with Multi Master User s Guide dbid The publication database ID of the publication database definition to be removed Examples The publication database definition identified by publication database ID 1 is removed java jar edb repcli jar removepubdb repsvrfile pubsvrfile prop gt pubdbid 1 Removing Publication Database Publication Database removed 8 3 10 Get Tables for a New Publication gettablesfornewpub The gettablesfornewpub command lists the tables and views that are available for inclusion in a new publication from a given publication database definition Synopsis gettablesfornewpub repsvrfile repsvrfile pubdbid dbid Parameters pubsvrfile The file containing the publication server login information dbid The publication database ID of the publication database definition whose available tables and views are to be listed Examples For the publication database definition identified by publication database ID 1 the tables available for inclusion in a publication are EDB DEPT EDB EMP and EDB JOBHIST The view available for inclusion in a publication is EDB SALESEMP java jar edb repcli jar gettablesfornewpub gt repsvrfile pubsvrfile prop pubdbid 1 Fetching tables views list EDB DEP
351. r node changes is pushed to the other master nodes in the following sequence e Pending transactions recorded in the shadow tables of the master definition node are replicated to the other master nodes Depending upon the host architecture and the setting of parallel synchronization options replication to the other master nodes may occur in parallel or serially See Section 5 8 2 2 for information on parallel synchronization e After the pending transactions have been pushed from the master definition node to all other master nodes the master node is selected that has the lowest publication database ID amongst the master nodes excluding the master definition Copyright 2012 EnterpriseDB Corporation All rights reserved 205 Postgres Plus xDB Replication Server with Multi Master User s Guide node The publication database ID is an internally generated positive integer assigned when the master node s publication database definition is created Pending transactions recorded in the shadow tables of this master node are pushed to all other master nodes including the master definition node in the same manner as described in the first bullet point e The process described in the second bullet point is repeated for each remaining master node in ascending order of publication database ID Note For clarity of the explanations and examples that follow it is assumed that parallel synchronization is not in use that is each replication process oc
352. re the Run Cleanup Job check box is selected Select the radio button for the cleanup frequency The frequency choices have the following meanings e After Every number of hours Schedules shadow table history cleanup to run continuously at an interval in hours that you specify Select this option if there are huge volumes of updates to the publication tables during the course of the day every day e Every Day at hour of day Schedules shadow table history cleanup to run once a day on the hour you choose Select this option if updates to the publication tables are frequent enough to require more than once a week cleanup but not needed more than once a day e Every selected day of week at hour of day Schedules shadow table history cleanup to run once a week on the day and at the hour you choose Select this option if updates to the publication tables are infrequent and you do not want to run cleanup manually Note A configuration option is available to force shadow table history cleanup after every synchronization replication See Section 9 3 1 8 for information on this option Copyright 2012 EnterpriseDB Corporation All rights reserved 246 Postgres Plus xDB Replication Server with Multi Master User s Guide Cleanup Job The synchronization history is maintained in the shadow tables by default You can schedule a cleanup job that will remove the synchronized transactions history from shadow tables on periodic basis V Run Cl
353. reated see Section 6 2 3 e Tables cannot be added nor removed from existing publications see sections 7 5 3 1 and 7 5 3 2 Copyright 2012 EnterpriseDB Corporation All rights reserved 410 Postgres Plus xDB Replication Server with Multi Master User s Guide e A publication table definition cannot be modified using the DDL change replication feature see Section 7 6 e Anew replication schedule cannot be created nor can an existing replication schedule be modified see sections 7 1 and 7 2 1 e A snapshot replication cannot be performed see Section 6 5 1 e The role of the master definition node cannot be switched to another master node see Section 6 9 e The conflict resolution options for a publication table cannot be changed see Section 6 8 A dialog box similar to the following appears if you attempt a restricted operation The xDB MMR trial license has expired Please contact EnterpriseDB technical support for license key Figure 236 Disallowed restricted mode operation You must register your xDB Replication Server product by entering a valid license key to re enable restricted operations See Section 3 3 for instructions on performing this operation Copyright 2012 EnterpriseDB Corporation All rights reserved 411
354. regions of clients Having the database servers physically close to clients can reduce latency with the database Multi master replication allows you to employ a WAN connected network of master databases that can be geographically close to groups of clients yet maintain data consistency across master databases 2 2 Replication Concepts and Definitions xDB Replication Server is a software product that enables the implementation of a replication system A replication system is software and hardware whose purpose is to make a copy of data from one location to another and to ensure the copied data is the same as the original over time xDB Replication Server applies the replication system concept to tables of Oracle SQL Server PostgreSQL and Postgres Plus Advanced Server database management systems The following sections present specific terms and concepts used when discussing xDB Replication Server Copyright 2012 EnterpriseDB Corporation All rights reserved 14 Postgres Plus xDB Replication Server with Multi Master User s Guide 2 2 1 Comparison of Single Master and Multi Master Replication There are two models of replication systems supported by xDB Replication Server e Single Master Replication SMR Changes inserts updates and deletions to table rows are allowed to occur in a designated master database These changes are replicated to tables in a slave database The replicated tables in the slave database are not permitted to
355. rk location of a subscription server changes after subscriptions have been created the publication server metadata must be updated with the new network location otherwise a communication failure occurs between the publication server and the subscription server that is made apparent by the following message that appears when you open the xDB Replication Console Copyright 2012 EnterpriseDB Corporation All rights reserved 259 Postgres Plus xDB Replication Server with Multi Master User s Guide File Publication Subscription Help S CECU Pens sai ts Replication Servers E Publication Server 192 168 2 7 9051 gt MMR Property pate 7 SMR Service status Stopped A g Subscription Server 192 168 2 7 9052 Subscription database count Not Available Subscription Service connection failure Figure 186 Subscription server connection failure The following are the steps to update the subscription server network location within a publication server s metadata Step 1 The publication server whose metadata you want to change must be running See Step 1 of Section 5 2 1 for directions on starting the publication server Step 2 Click the secondary mouse button on the Publication Server node and choose Update Subscription Servers The Update Subscription Servers dialog box appears Note If the error message box reappears click the OK button and repeat Step 2 Copyright 2012 EnterpriseDB Corp
356. rk location of the host running the publication server database or operating system user names and passwords and so forth The aforementioned information is saved in the replication system metadata when a publication is created Changes to these attributes result in inaccurate replication system metadata which in turn may result in errors during subsequent replication attempts or replication system administration This section describes how to update the metadata stored for the publication server the publication database definition and publications in order to keep the information consistent with the actual replication system environment 7 5 1 Updating a Publication Server There are two aspects of metadata related to the publication server that may need to be updated depending upon the change in the host environment e Ifthe network location IP address or port number user name or password of the publication server changes and if you have saved this information in the server login file you need to update the server login file with the new information e Ifthe network location IP address or port number of a subscription server changes then for each publication server managing a publication associated with a subscription of the changed subscription server you must update the publication server s metadata with the subscription server s new network location This type of update applies only to single master replication systems
357. rows In Postgres foreign key constraints are implemented using triggers so in actuality the Migration Toolkit disables triggers on the target tables by setting column reltriggers of pg _catalog pg class to zero for each target table No user not even a superuser is allowed to directly modify the data in a Postgres system catalog table unless the following conditions are satisfied e The database user attempting to modify the rows of a system catalog table is a superuser e Inthe Postgres system catalog table pg_catalog pg_ authid the column rolcatupdate is set to true for the row identifying the superuser attempting to update a system catalog table To verify that a user has the privilege to update the system catalog tables select the user name under the Login Roles node in pgAdmin Postgres Enterprise Manager Client in Advanced Server The Update Catalogs property should be set to Yes File Edit Plugins View Management Tools Help AGOILD WSO BERF if Server Groups Properties X Statistics Dependencies a B Servers 1 Property Value e a peta ae Server 9 1 lo Name aise 0 eb E omm 17113 p subdb E Account expires a xdb E Can login Yes c Tablespaces 2 F Superuser Yes be Group Roles 0 Create databases No J Login Roles 2 E create roles No E Update catalogs Yes j B enterprisedb Inherits Yes o subuser Figur
358. rt on which the master definition node is listening for connections e User The database user name for the master definition node created in Step 1 of Section 6 1 1 e Password Password of the database user e Database Enter the database name of the master definition node e Node Priority Level An integer from 1 to 10 which is the priority level assigned to this master node for conflict resolution based on node priority The highest priority is 1 while the lowest is 10 See Section 6 6 3 for information on conflict resolution strategies The default is 1 for the master definition node This database will be added as Master Definition Node Database Type Postores Plus Advanced Server Postgres Plus Advanced Server Database Information Cg Please specify Postgres Plus Advanced Server database information Host 192 168 10 102 Port User pubuser Password 068006 Database edb Figure 112 Publication Service Add Database dialog box for the master definition node Step 4 Click the Test button If Test Result Success appears click the OK button then click the Save button Copyright 2012 EnterpriseDB Corporation All rights reserved 184 Postgres Plus xDB Replication Server with Multi Master User s Guide This database will be added as Master Definition Node Database Type Postgres Plus Advanced Server Database Information Node Priority
359. rtain types of Oracle partitioned tables is a set of inherited tables In these cases the SQL DELETE statement is used on the inherited child tables instead of truncation See Section 9 3 1 4 for additional information on replicating Oracle partitioned tables A server configuration option is available that forces the snapshot replication process to use the Oracle database link utility instead of JDBC coPY to populate the Postgres target tables from an Oracle publication Oracle database link provides an additional performance improvement over JDBC COPY See Section 5 8 1 for information on using the Oracle database link option See Section 5 8 1 for information on various configuration options to optimize snapshot replication Copyright 2012 EnterpriseDB Corporation All rights reserved 55 Postgres Plus xDB Replication Server with Multi Master User s Guide 2 4 4 2 What Happens During Synchronization Replication In synchronization replication changes made to the source tables since the last replication occurred are applied to the target tables using SQL INSERT UPDATE and DELETE statements However the SQL statements run against the target tables are not the same SQL statements that were run against the source tables If a publication in a single master replication system is created that will be used in synchronization replications the publication server installs an insert trigger an
360. rver The following is an example of the content of an xDB Replication Configuration file user enterprisedb port 5444 password ygJ 9AxoJEX8 54e1lcVIJPTw type enterprisedb host localhost database xdb The value you substitute for pub_ipaddr is the network IP address where the publication server is running Note The network IP address you substitute for pub _ipaddr must not be the loopback address 127 0 0 1 However the publication server does require access to the xDB Control database using the loopback address as well This access is already granted in the default pg_hba conf file by the following entry host all all 12005 1 32 md5 The following shows an example of the pg_hba conf file TYPE DATABASE USER CIDR ADDRESS METHOD local is for Unix domain socket connections only local all aLI md5 IPv4 local connections host xdb enterprisedb 192 168 10 102 32 md5 host all all 127 0 0 1 32 md5 IPv6 local connections host all all AZS md5 Master Nodes On each database server running a master node the following is needed to allow access to the database host masternode db masternode user pub ipaddr 32 md5 The value you substitute for masternode_db is the name of the database you intend to use as the master node The value you substitute for masternode_user is the database user name you created in Step 1 of Section 6 1 1 or Step 1 of Section 6 1 2 For a database named edb
361. rver 192 168 2 7 9051 et g Subscription Server 192 168 2 7 9052 R Postgres Plus Advanced Server 192 sales_dept_S ii Remove Schedule Figure 158 Removing the schedule Step 4 In the Removing Schedule confirmation box click the Yes button Copyright 2012 EnterpriseDB Corporation All rights reserved 233 Postgres Plus xDB Replication Server with Multi Master User s Guide tq Replication Servers Publication Server 192 168 2 7 9051 Subscription Server 192 168 2 7 9052 QP Postgres Plus Advanced Server 192 ef H sales _dept 2012 06 08 01 00 0017 MON WED Figure 159 Removing Schedule confirmation If you click the Refresh icon in the tool bar you will notice that schedule information no longer appears in the information window z3 Replication Servers Q Publication Server 192 168 2 7 9051 S Subscription Server 192 168 2 7 9052 Figure 160 Information window after schedule removal Copyright 2012 EnterpriseDB Corporation All rights reserved 234 Postgres Plus xDB Replication Server with Multi Master User s Guide 7 3 Viewing Replication History A summary of replications performed on each subscription or master node can be viewed in the xDB Replication Console A detailed replication history showing each insert update and deletion made against each target table can be viewed as well See Section 2 4 4 2 for a discussion on how changes are applied to target
362. rypted form password ygu 9AxoJEX854elcVIJPTw Copyright 2012 EnterpriseDB Corporation All rights reserved 316 Postgres Plus xDB Replication Server with Multi Master User s Guide These files can be located in any directory as long as they can be read by the operating system user running the xDB Replication Server CLI In your file be sure to replace the values of the following fields with the values for your publication server or subscription server e Host e Port e User e Password This is the same information with which you would need to register the publication server or subscription server if you were using the xDB Replication Console See Section 5 2 1 for additional information on registering the publication server See Section 5 3 1 for information on registering the subscription server The following example illustrates how the repsvrfile parameter is used along with the printpublist command S java jar edb repcli jar printpublist repsvrfile pubsvrfile prop Preaimealioe joulollsieeneslems osp analysts managers dept_emp emp pub 8 2 4 Using Encrypted Passwords in Text Files When using the xDB Replication Server CLI text files are used to store certain information which may include user names and passwords An example is the files containing publication server and subscription server login information used with the repsvrfile parameter In the file specified with parameter repsvrfile the password fi
363. s Plus xDB Replication Server with Multi Master User s Guide skipAnalyze Set the skipAnalyze option to true if you want to skip execution of the ANALY ZE command after loading Postgres subscription tables The ANALYZE command gathers statistical information on the table contents These statistics are used by the query planner skipAnalyze true false The default value is false snapshotParallelLoadCount Note This option applies to the subscription server only The snapshotParallelLoadCount option controls the number of threads used to perform snapshot data replication in parallel mode The default behavior is to use a single thread However if the target system architecture contains multi CPUs cores you can specify a value greater than 1 normally equal to the CPU core count to fully utilize the system resources snapshotParallelLoadCount n The default value is 1 lobBatchSize If a table contains a column with a data type typically used for large objects such as BY TEA BLOB or CLOB there is a greater possibility that a heap space error may occur because of a potentially large amount of data hundreds of megabytes brought into memory In order to minimize the possibility of this error a snapshot replication loads tables containing a large object data type one row at a time using a single INSERT statement per batch If however the large object data type column is known to contain rela
364. s as well as information on various other configuration options to optimize synchronization replication 2 4 4 3 When to Use Snapshot or Synchronization Generally synchronization would be the quickest replication method since it only applies changes to the target tables since the last replication occurred However if a large percentage of rows are changed between each replication there may be a point where it would be faster to completely reload the target tables using a snapshot than to execute individual SQL statements on a large percentage of rows as would be done for synchronization replication Experimentation may be necessary to determine if and at what point a snapshot would be faster Snapshot replication may be an option for tables with the following characteristics e Tables are relatively small in size e A large percentage of rows are changed between replications Synchronization replication is the better option for tables with the following characteristics e Tables are large in size e A small percentage of rows are changed between replications In a single master replication system if you find that one group of tables consistently replicates faster using snapshot replication then these tables can be made part of a snapshot only publication while the remaining tables can be members of a publication that uses synchronization replication 2 4 4 4 When to Use On Demand Replication The xDB Replication Console and xDB Repli
365. s must be used In addition the correct IP addresses must be kept up to date in the replication system metadata should they change in the networked environment 2 4 5 3 Multi Master Replication Distributed Hosts In a multi master replication system the Postgres database servers running the master nodes can be running on a single or multiple hosts The following example illustrates two master nodes running on database servers on separate hosts as well as a master node running on the same database server as the publication server Postgres host Postgres host xDB Replication Console or xDB Replication Server CLI xDB Replication Server xD o Postgres host Figure 23 Multi master replication on distributed hosts Copyright 2012 EnterpriseDB Corporation All rights reserved 62 Postgres Plus xDB Replication Server with Multi Master User s Guide 3 Installation This chapter describes how to install xDB Replication Server Installation of xDB Replication Server is done with Stack Builder or StackBuilder Plus depending upon whether you are using PostgreSQL or Postgres Plus Advanced Server e For PostgreSQL Install xDB Replication Server from the Postgres Plus Solution Pack using Stack Builder after you have installed PostgreSQL e For Postgres Plus Advanced Server Install xDB Replication Server using StackBuilder Plus after you have installed Postgres Plus Advanced Server The following section describes the in
366. s requires the following e The subscription database user must have superuser privileges Copyright 2012 EnterpriseDB Corporation All rights reserved 107 Postgres Plus xDB Replication Server with Multi Master User s Guide e The subscription database user must have the ability to modify the system catalog tables in order to disable foreign key constraints on subscription tables See appendix Section 9 3 4 for more information on this requirement You have the following two choices for choosing the subscription database user name e Use the Postgres user name postgres created upon installation of PostgreSQL enterprisedb for Advanced Server installed in Oracle compatible configuration mode for the subscription database user name If you choose this option skip Step 1 and proceed to Step 2 e Create a new subscription database user name For this option proceed to Step 1 Step 1 Create a superuser as the subscription database user CREATE ROLE subuser WITH LOGIN SUPERUSER PASSWORD password Step 2 Create or choose the subscription database The names of the schemas containing the publication tables and views become the names of the Postgres schemas for the subscription tables The subscription server creates these schemas in the subscription database when the subscription is created If schemas with these names already exist in the subscription database the existing schemas will be used to store the
367. s to be included in the publication Section 5 2 3 discusses creating a publication for a single master replication system See Section 6 2 3 for a multi master replication system 2 3 2 5 Subscription Server Note The subscription server applies only to single master replication systems You do not register a subscription server when creating a multi master replication system Copyright 2012 EnterpriseDB Corporation All rights reserved 35 Postgres Plus xDB Replication Server with Multi Master User s Guide When you install a subscription server on a host the subscription server program is installed started and establishes a session with the xDB Control database that you designated during the installation process The connection information for the xDB Control database is stored in the xDB Replication Configuration file created and stored on the host s file system during subscription server installation The first step in creating a subscription is to identify the subscription server that is to be used to manage the subscription This process is called registering the subscription server Using the xDB Replication Console or the xDB Replication Server CLI a subscription server is registered by giving the IP address and port number of the host on which the subscription server is running along with the user name and password stored in the xDB Replication Configuration file located on the host running the subscription server This
368. se node and any of its publications Copyright 2012 EnterpriseDB Corporation All rights reserved 265 Postgres Plus xDB Replication Server with Multi Master User s Guide File Publication Subscription Help S Swe COGS sis g Replication Servers E Publication Server 192 168 2 7 9051 lt General Realtime Monitor Replication History amp 2 MMR Buan 2 83 SMR Host 192 168 2 6 2 4 AEREE Port 1521 yf sales_dept SiD on User pubuser Figure 192 Updated publication database 7 5 3 Updating a Publication Existing publications can be updated in the following ways e Tables can be added to the publication e Tables can be removed from the publication e Filter clauses can be viewed updated or removed from publication tables 7 5 3 1 Adding Tables to a Publication For a single master replication system you can add tables to a publication but only if there is no subscription associated with the publication If there is an existing subscription you have the following two choices update the original publication by adding the additional tables or create a new publication and subscription to replicate the additional tables For a multi master replication system you can add tables to a publication even while there are additional master nodes in the replication system Note The following discussion applies only to single master replication systems To update the original publication by a
369. ser GRANT SELECT ON edb jobhist TO pubuser GRANT SELECT ON edb salesemp TO pubuser 5 1 2 2 SQL Server Publication Database In SQL Server an application gains access to the database server by supplying a SQL Server login and its associated password When an application connects to a particular database the application assumes the identity and privileges of a database user that has been defined in that database The database users in any given database are independent of database users in other databases with respect to their properties such as their role memberships and privileges In fact the same database user name can be defined in more than one database each with its own distinct properties In each database a database user can be mapped to a SQL Server login When an application connects to a database using a SQL Server login to which a database user has been mapped the application assumes the identity and privileges of that database user Copyright 2012 EnterpriseDB Corporation All rights reserved 102 Postgres Plus xDB Replication Server with Multi Master User s Guide When using a SQL Server database as the publication database a number of database users must be defined and mapped to a SQL Server login according to the following rules e A SQL Server login must exist that is to be used by the publication server to connect to SQL Server The SQL Server login and password are specified when creating the publication dat
370. ser interface when creating a replication system The entire replication system is completed with the addition of the following components Copyright 2012 EnterpriseDB Corporation All rights reserved 26 Postgres Plus xDB Replication Server with Multi Master User s Guide User interfaces for configuring and maintaining the replication system One or more publication databases for a single master replication system One or more subscription databases for a single master replication system One master definition node for a multi master replication system One or more additional master nodes for a multi master replication system The user interface publication server subscription server xDB Control database publication database subscription database and master nodes can all run on the same host or on separate networked hosts Any number of user interfaces can be used at any time to access any number of publication servers and subscription servers on the network as long as the network locations user names and passwords of the publication and subscription servers are known Any number of publication and subscription databases can participate in a single master replication system Any number of master nodes can participate in a multi master replication system The following sections describe each component in more detail 2 3 1 1 Publication Server The publication server creates and manages the metadata for publications When a
371. ser has insufficient privileges to manage publications Grant required privileges as listed below and then proceed with operation Resolution An Oracle publication database user must have CONNECT RESOURCE and CR TRIGGER privileges Copyright 2012 EnterpriseDB Corporation All rights reserved 376 Postgres Plus xDB Replication Server with Multi Master User s Guide Error Messages and Resolutions The initial snapshot is not performed for this publication Please take the snapshot first and then proceed with the synchronize operation Resolution A snapshot replication must be performed before the first synchronization replication Perform an on demand snapshot replication It is recommended to use a network IP address the loopback address may result in connectivity issues Resolution This warning is given when localhost or 127 0 0 1 is specified as the host address of a replication system component If is strongly recommended that all replication system components are identified by their specific IP address on the network The log triggers creation failed for one or more publication tables Make sure the database is in valid state and user is granted the required privileges Resolution Either the user does not have the trigger creation privilege or there is a database server problem The database server message is displayed as part of the error INo JDBC Client driver is configured for the Oracle
372. ser s Guide Juice Places System QS amp accessories amp Graphics Internet SS Office UP Postgres Pius Add ons bY Postgres Plus Advanced Server 9 1 a Expert Configuration gt Programming iB Run SQL Command Line gt M Sound amp video Documentation D System Tools StackBuilder Plus B Add Remove Software Figure 24 Postgres application menu Step 3 For Linux only Depending upon your Linux host a dialog box or a prompt appears requesting the root account s password Enter the root password and click the OK button Copyright 2012 EnterpriseDB Corporation All rights reserved 64 Postgres Plus xDB Replication Server with Multi Master User s Guide runStackBuillderPlus sh No graphical su sudo program could be found on your system This window must be kept open while StackBuilder Plus is running Please enter the root password when requested Password Figure 25 Enter root account password Step 4 The StackBuilder Plus welcome screen appears Select your Postgres installation from the drop down list and click the Next button Copyright 2012 EnterpriseDB Corporation All rights reserved 65 Postgres Plus xDB Replication Server with Multi Master User s Guide StackBullder Pius 2 0 4 x Welcome to StackBuilder Plus This wizard will help you install additional and update installed software to complement your PostgreSQL or EnterpriseDB Postgres Plus installation To be
373. specified then a schedule is created for the publication no_of sec The number of seconds between scheduled replications This can be any integer greater than 0 hour The hour of the day based on a 24 hour clock This can be any integer from 0 to 23 minute The minute of the hour This can be any integer from 0 to 59 day of week Copyright 2012 EnterpriseDB Corporation All rights reserved 364 Postgres Plus xDB Replication Server with Multi Master User s Guide The day of the week This can be any of the following values SUN MON TUE WED THU FRI or SAT This value is case insensitive so Sun and sun will work as well as SUN v month The month of the year This can be any of the following values JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV or DEC This value is case insensitive so Jan and jan will work as well as JAN day of month The day of the month This can be any integer greater than or equal to 1 and less than or equal to the number of days in month cron expression A cron expression See appendix Section 9 3 3 for information on writing a cron expression Examples In the following example a schedule is created to perform synchronization replication on publication emp pub subordinate to the master definition node whose publication database ID is 6 Replication is to occur daily at 8 00 AM java jar edb repcli jar confschedulemmr 6 pubname emp pub
374. specified in the definition along with the database network location and database identifier e A subscription named sub is created subordinate to the subscription database definition When the subscription is created the subscription server creates schemas named S1 and S2 in the subscription database The table definitions for tables A B and C are also created at this time When replication occurs the publication server populates these tables with rows from the publication The following screen capture shows how the logical components of this replication system appear in the xDB Replication Console replication tree Fie Publication Subscription Help t Publication Server 192 168 2 7 9051 Se SMR g Oracle 192 168 2 6 1521 xe pubuser G ty pub S1 A E 52 B H E s2 c iDa MMR S Subscription Server 192 168 2 7 9052 R Postgres Plus Advanced Server 192 168 2 7 5444 subdb subuser amp S sub amp ty pub H E S1 4 2 B H E 2 c Figure 12 Oracle to Postgres replication tree Copyright 2012 EnterpriseDB Corporation All rights reserved 39 Postgres Plus xDB Replication Server with Multi Master User s Guide See Chapter 4 for an introduction to the xDB Replication Console 2 3 3 2 SQL Server to PostgreSQL or Advanced Server Replication The following is an illustration of a basic SQL Server to PostgreSQL or Advanced Server single master replication system A single publication in SQL Serv
375. ssfully saved a Publication Database node is added to the replication tree under the MMR type node of the Publication Server node Copyright 2012 EnterpriseDB Corporation All rights reserved 193 Postgres Plus xDB Replication Server with Multi Master User s Guide Help GJU Ge Age to Replication Servers E Publication Server 192 168 10 102 9051 BE SMR S52 MMR i P Postgres Plus Advanced Server 192 168 10 102 5444 edb pubuser MDN G g emp_pub H E edb dept Es edb emp Postgres Plus Advanced Server 192 168 10 103 5444 mmrnode mmruser Sy emp_pub H E edb dept es edb emp File Publication Subscription Figure 121 Replication tree after adding an additional master node General Property Host 192 168 10 103 Port 5444 Database mmrnode User mmruser MDN No Publication count 1 Scheduled job status Not available Unlike the master definition node the label MDN does not appear at the end of the node in the replication tree The MDN field is set to No in the Property window to indicate this is not the master definition node In addition a Publication node appears under the newly added master node This Publication node represents the publication in the master definition node which is replicated to the master node If in Step 3 you checked the Perform Initial Snapshot check box an initial snapshot replication is performed and the log of the snapshot is displayed
376. sssscsssscsessscesssccessssesesscesenssceseeees 190 6 4 Metadata Created in Master Nodes csscccsssssssssscssssscssssscscssnceesesesenssesens 195 6 5 On Demali aialiCatigir cccsscccsssscsssscesssncesssrsessssessnscessacesensseseneessnaceeens 196 6 5 1 Performing Snapshot Replication ssssssssessesssessseeessseesseesserssersssresseeesseese 196 6 5 2 Performing Synchronization Replication seseseeeseeeesssessesssesesereessressre 200 6 6 Conflict ResOlut0on sssini esise easain aiaia 203 Ge Conflict Type Sirei aie gated nad E N cot hatet ald 203 0 6 2 Conflict Detect OM x sores a e s E R T EE 205 6 6 3 Conflict Resolution Strategies seseeessseesseesseesseesseeesseessrssessseeeesseesseese 207 6 6 4 Conflict Prevention Uniqueness Case ssessseeesseeesseesseesserssereesseesses 208 6 6 5 Example Conflict Resolution wi cece ceescecesseecesececeeeeeceeeeeceeeeeceeeeeeeeeeesaes 208 6 7 Viewing Conflict HIStOr yi sisinceecsaeanicees acadces dees ation aadincegecedaesaaedueedehasdecnacaosteseds 209 6 8 Updating the Conflict Resolution Options cceeececesceeceseeeeeeeeeeeseeeesaeees 212 Copyright 2012 EnterpriseDB Corporation All rights reserved 5 Postgres Plus xDB Replication Server with Multi Master User s Guide 6 9 Switching the Master Definition Node 0 ceeeceeesceceeececeeeeeceeeeeceteeeeneeeees 216 6 10 Optimizing Performante esseet neess ni terai oiei 219 T Commo
377. st counting from left to right starting with 1 of a view in the views parameter list to which filter clause filter vnis to be applied filter vn For SMR only The filter clause to be applied to the view in the views parameter list at the position indicated by ordinal vn repgrouptype Specify s if this command applies to a single master replication system Specify m if this command applies to a multi master replication system If omitted the default is s Examples In the following example table edb jobhist and view edb salesemp are added to an existing publication named analysts managers java jar edb repcli jar addtablesintopub analysts managers gt repsvrfile pubsvrfile prop tables edb jobhist gt views edb salesemp Adding tables to publication analysts managers Tables edb jobhist TABLE edb salesemp VIEW Copyright 2012 EnterpriseDB Corporation All rights reserved 336 Postgres Plus xDB Replication Server with Multi Master User s Guide Filter clause null null Publication updated successfully 8 3 15 Removing Tables From a Publication removetablesfrompub Synopsis removetablesfrompub pubname repsvrfile pubsvrfile tables schema_tl table_ 1 schema_vl view 1 schema_t2 table 2 schema v2 view 2 See Section 7 5 3 2 for additional information on removing tables from a publication Note The schema names table names and view names that you sup
378. stall the components in the default location shown Click the Next button Copyright 2012 EnterpriseDB Corporation All rights reserved 74 Postgres Plus xDB Replication Server with Multi Master User s Guide Installation Directory Please specify the directory where xDB Replication Server will be installed Installation Directory opt PostgresPlus 9 1AS BitRock Installer Figure 37 Installation directory Step 13 If you do not want a particular xDB Replication Server component installed on this particular host uncheck the box next to the component name Click the Next button Copyright 2012 EnterpriseDB Corporation All rights reserved 75 Postgres Plus xDB Replication Server with Multi Master User s Guide Select Components Select the components you want to install clear the components you do not want to install Click Next when you are ready to continue X Replication Console X Publication Server X Subscription Server BitRock Installer Figure 38 Select components Step 14 For PostgreSQL only In the Account Registration screen select the radio button that applies to you Click the Next button Note For Advanced Server only Proceed to Step 15 Copyright 2012 EnterpriseDB Corporation All rights reserved 76 Postgres Plus xDB Replication Server with Multi Master User s Guide Registration required at www enterprisedb com By If you do not have an account click Next to register
379. stallation of xDB Replication Server 3 1 Installing With Stack Builder or StackBuilder Plus Stack Builder and StackBuilder Plus are programs used to download and install add on products and updates to PostgreSQL and Postgres Plus Advanced Server Stack Builder is used for PostgreSQL StackBuilder Plus is used for Postgres Plus Advanced Server Stack Builder and StackBuilder Plus are very similar in functionality and look and feel differing primarily in the list of products offered This section demonstrates the installation of xDB Replication Server using StackBuilder Plus for Advanced Server Steps are noted where the installation process differs for installation on PostgreSQL using Stack Builder Step 1 For PostgreSQL only You must have Java runtime version 1 5 or later installed on the hosts where you intend to install any xDB Replication Server component xDB Replication Console publication server or subscription server Note The Oracle Java formerly known as Sun Java runtime product must be used Follow the directions for your host operating system to install Java runtime For Advanced Server a Java runtime is supplied and installed as part of the Advanced Server installation process Step 2 From the host s application menu open the Postgres menu and choose Stack Builder or StackBuilder Plus Copyright 2012 EnterpriseDB Corporation All rights reserved 63 Postgres Plus xDB Replication Server with Multi Master U
380. stgres Plus xDB Replication Server with Multi Master User s Guide 2 3 2 7 Subscription Note The subscription applies only to single master replication systems You do not create a subscription when creating a multi master replication system Subordinate to a subscription database definition one or more subscriptions can be defined A subscription associates a publication to a subscription database to which the publication s tables and views are to be replicated Each subscription can be associated with one and only one publication Section 5 3 3 discusses creating a subscription 2 3 3 xDB Replication System Examples This section contains examples of replication systems and how the logical components are used to define them In the accompanying diagrams the logical components represented by nodes in the replication tree of the xDB Replication Console are superimposed on physical component diagrams The logical components are shaded in yellow to aid in identifying them in the diagrams 2 3 3 1 Oracle to PostgreSQL or Advanced Server Replication The following is an illustration of a basic Oracle to PostgreSQL or Advanced Server single master replication system A single publication in Oracle contains tables from two schemas that are replicated to a database residing in either PostgreSQL or Postgres Plus Advanced Server Copyright 2012 EnterpriseDB Corporation All rights reserved 37 Postgres Plus xDB Replication Server with
381. stgresPlus 9 1AS jre bin Path Note For a PostgreSQL installation you must perform the same process as previously described but using the location of where you installed the Java Runtime Environment 8 2 General Usage This section explains the general usage rules for the xDB Replication Server CLI 8 2 1 Running xDB Replication Server CLI You can run the xDB Replication Server CLI from any host on which you can run the XDB Replication Console The xDB Replication Server CLI is run by executing the java runtime program and specifying the following arguments to the java program e The path to the xDB Replication Server CLI jar file edb repcli jar e An xDB Replication Server CLI command e One or more publication names or subscription names if the command acts on a publication or subscription e Parameters and their values that are applicable to the command The Java jar file edb repcli jar is located in directory XDB_HOME bin Each xDB Replication Server CLI command has the following general syntax command pubname subname parameter value In the preceding syntax diagram command is the name of an xDB Replication Server CLI command The command name must be prefixed by a hyphen character If the Copyright 2012 EnterpriseDB Corporation All rights reserved 314 Postgres Plus xDB Replication Server with Multi Master User s Guide command acts on a publication the name of the publication represente
382. subscription database ID of the subscription database definition subordinate to which the new subscription is to be added pubsvrfile Copyright 2012 EnterpriseDB Corporation All rights reserved 355 Postgres Plus xDB Replication Server with Multi Master User s Guide The file containing the publication server login information of the publication server under which the publication is subordinate to which the new subscription is to be associated pubname The publication to which the new subscription is to be associated Examples In the following example a subscription named dept _emp_ sub is created in the Advanced Server subscription database identified by subscription database ID 2 The subscription is associated with a publication named dept _emp java jar edb repcli jar createsub dept emp sub S subsvrfile subsvrfile prop gt stisclosiel 2 gt pubsvrfile pubsvrfile prop gt pubname dept remp Creating subscription Subscription created successfully 8 3 32 Printing a Subscription List printsublist For SMR only The printsublist command prints a list of subscription names Synopsis printsublist repsvrfile subsvrfile subdbid dbid Parameters subsvrfile The file containing the subscription server login information dbid The subscription names subordinate to the subscription database definition specified by dbid are printed Examples S java Jar edb repcli jar printsublist repsvrfi
383. systems are noted with For MMR only 7 1 Creating a Schedule A schedule establishes recurring points in time when replication is to occur In a single master replication system once a schedule is created the subscription server initiates replications according to the schedule until either the schedule is changed or removed In a multi master replication system the publication server handles this process See Section 7 2 for changing or removing a schedule When a scheduled replication is to take place all components of the replication system must be running Publication database server Subscription database server applies only to single master replication systems xDB Control database server Publication server Subscription server applies only to single master replication systems If any of the preceding components are not running at the time of a scheduled replication then replication does not occur at that point in time The replication occurs at the next scheduled replication time when all applicable replication system components are running For synchronization replications changes that have occurred on the source tables that were not replicated due to a skipped scheduled replication are maintained as pending transactions in the shadow tables of the source database All changes since the last Copyright 2012 EnterpriseDB Corporation All rights reserved 221 Postgres Plus xDB Replication Server with Multi Master User s
384. t SQL STORED PROCEDURE pubuser CreateUniTxSet SQL STORED PROCEDURE pubuser GetNewTxsCount SQL STORED PROCEDURE pubuser JobCleanup SQL STORED PROCEDURE pubuser JobCreateTxSet SQL STORED PROCEDURE pubuser LoadPubTableList SQL STORED PROCEDURE pubuser nextval SQL STORED PROCEDURE pubuser RemoveCleanupJob SQL STORED PROCEDURE pubuser RemoveCreateTxSetJob SQL STORED PROCEDURE pubuSser splereakresequence SQL STORED PROCEDURE pubuser sp_ dropsequence SQL STORED PROCEDURE pubuser rrep common seq USER_TABLE pubuser rrep lock USER TAB pubuser rrep mmr pub group USER _ TAB pubuser rrep mmr txset USER_TAB pubuser rrep properties USER _ TAB pubuser rrep publication subscriptions USER TAB pubuser rrep publication tables USER TAB pubuser rrep tables USER _ TAB pubuser rrep tx seq USER_TAB pubuser rrep texset USER_TAB pubuUSeEr ruep Exseu mealteh USER TAB Copyright 2012 EnterpriseDB Corporation All rights reserved 388 Postgres Plus xDB Replication Server with Multi Master User s Guide UObISSie wie esse ole USER_TAB pubuser r repitxSeri eg USER _ TAB pubuser rrst edb dept USER _ TAB pubusex rrst edb emp USER_TAB 31 rows affected For non snapshot only publication tables triggers are created as well that reside in the schema containing the publication tables as shown by the following query 1 gt USE edb 2 CO Changed database context
385. t contains only the edb replicator sub schema Note If all of your replication systems are multi master the xDB Control database used by the publication server contains only the edb replicator pub schema Step 7 Delete schemas edb replicator puband edb replicator sub and all their database objects from the xDB Control database The following psql session shows this process edb c xdb enterprisedb Copyright 2012 EnterpriseDB Corporation All rights reserved 393 Postgres Plus xDB Replication Server with Multi Master User s Guide You are now connected to database xdb as user enterprisedb xdb DROP SCH NOTICE DETAIL Tie drop drop drop drop drop drop drop drop drop drop drop drop drop DROP xdb xdb DROP SCH cascades cascades cascades cascades cascades cascades cascades cascades cascades cascades cascades cascades cascades SCHEMA drop cascad tabl tabl tabl tabl tabl tabl Habl tabl tabl tabl tabl tabl tabl to TO to to to to TO to to to TO TO to EMA edb replicator pub CASCADE drop cascades to 14 other objects Ss to sequence e edo zepl _ Sell scejoll _ Selo iso Become mecibmaejoilt _ Selo ieSjoll _ Selo ssjoll me ciomaejoil mecismaciols me ciomaeyoile mecdbereril _ Selle scejol me ciomaeyoile oonoO 070 000 00 0 0 Bedbmuepliicaronm pub ase pmcOnnonmsec icator pub icator pub icator pub icator pub
386. t information after performing an operation Clicking the Refresh icon ensures that the latest information is shown in the replication tree and in the information window File Publication Subscription Help OLERE Te eS Figure 55 Refresh icon 4 1 2 Create Publication The Create Publication icon is activated when a Publication Database node is highlighted in the replication tree Copyright 2012 EnterpriseDB Corporation All rights reserved 93 Postgres Plus xDB Replication Server with Multi Master User s Guide ta Replication Servers oe Publication Server 192 168 2 7 9051 Ba SMR Figure 56 Create Publication icon 4 1 3 Publication Management The Remove Publication icon Add Publication Tables icon and Remove Publication Tables icon are activated when a Publication node is highlighted in the replication tree bd Replication Servers oe Publication Server 192 168 2 7 9051 4 sr ag Oracle 192 168 2 3 1521 xe pubuser 2 amp era Figure 57 Remove Publication Add Publication Tables and Remove Publication Tables icons 4 1 4 Create Subscription The Create Subscription icon is activated when a Subscription Database node is highlighted in the replication tree Copyright 2012 EnterpriseDB Corporation All rights reserved 94 Postgres Plus xDB Replication Server with Multi Master User s Guide x DB Replication Conse bd Replication Servers E e Publication Server 192 168 2 7 9051 i
387. tabase definition the database user name is entered in the Publication Service Add Database dialog box see Section 6 2 2 CREATE ROLE pubuser WITH LOGIN SUPERUSER PASSWORD password 6 1 2 Preparing Additional Master Nodes The following steps illustrate the creation of a database user and a database for an additional master node When creating the publication database definition for an additional master node a database user name must be specified that has the following characteristics e The database user can connect to the master node e The database user has superuser privileges e The database user must have the ability to modify the system catalog tables in order to disable foreign key constraints on the publication tables See appendix Section 9 3 4 for more information on this requirement There are also two possible options available with respect to how the publication tables are to be created in the master node e Allow the publication server to create the publication table definitions in the master node by copying the definitions from the master definition node at the time you add the publication database definition for the master node e Define the publication tables in the master node beforehand by running SQL DDL statements in the PSQL command line utility program or by using Postgres Enterprise Manager Client to create the tables If you create the table definitions manually as descr
388. tabase server network location if the corresponding location change was made to the database server that accesses the publication database e The database identifier such as the Oracle service name SQL Server database name or Postgres database name if the corresponding name change was made on the database server Step 1 Make sure the database server that you ultimately wish to save as the publication database definition is running and accepting client connections Step 2 Make sure the publication server whose node is the parent of the publication database definition you wish to change is running and has been registered in the xDB Replication Console you are using See Section 5 2 1 for directions on starting and registering a publication server Step 3 Select the Publication Database node corresponding to the publication database definition that you wish to update Copyright 2012 EnterpriseDB Corporation All rights reserved 263 Postgres Plus xDB Replication Server with Multi Master User s Guide File Publication Subscription Help ta Replication Servers General Realtime Monitor Replication History B S Publication Server 192 168 2 7 9051 eda MMR Propeity 8S SMR Host 192 168 2 6 Oracle 192 168 2 6 1521 xe pubus Port 1521 SID xe User pubuser Figure 189 Selecting a publication database definition for update Step 4 From the Publication menu choose Publication Database and
389. tadata schemas and their database objects are intact for Copyright 2012 EnterpriseDB Corporation All rights reserved 392 Postgres Plus xDB Replication Server with Multi Master User s Guide all publication database definitions then chances are that the problem lies elsewhere Recheck the checklist in Section 9 2 3 Step 6 Locate the metadata of the publication and subscription servers The database objects for the main metadata are located in the xDB Control database in schemas _edb replicator puband edb replicator sub These schemas are shown in the following File Edit Plugins View Management Tools Help LGEOVNEDE WiGS6 BBY 8 Servers 1 B F Postgres Plus Advanced Server 9 1 localhost 9 aS Databases 3 E Properties X Statistics Schema Owner _edb_replicator _pub enterprisedb _edb_replicator_sub enterprisedb R edb gS y E P pra db _edb_scheduler enterprisedb n xdb public enterprisedb E Catalogs 4 H Extensions 3 H 9 _edb_replicator_pub H _edb_replicator_sub H Q _edb_scheduler 8 public Figure 231 Metadata database objects in the xDB Control database Note If the publication server and subscription server are running on separate hosts each with their own xDB Control database then the database on the publication server s host contains only the edb replicator pub schema and the database on the subscription server s hos
390. tarted since copying the Oracle JDBC driver ojdbc14 jar to the 1ib jdbc subdirectory of your xDB Replication Server installation you must restart the publication server For Linux only You can verify the publication server is running by using the following command Copyright 2012 EnterpriseDB Corporation All rights reserved 116 Postgres Plus xDB Replication Server with Multi Master User s Guide ps aux grep pubserver This is shown by the following ps aux grep pubserver 502 S221 OWc8 2 9 SYSI9G S2I92 F Sal LTS Se ORTON opt PostgresPlus 9 1AS jre bin java Djava awt headless true jar edb repserver jar pubserver 9051 user S47 OO O 3996 688 pts 1 R AD sail 0 00 grep pubserver If the publication server is running and you wish to restart it run script etc init d edb xdbpubserver with the restart option Run the script as the operating system user that you chose during installation in the Publication Subscription Service Account screen in Step 18 of Section 3 1 For an xDB Replication Server installation done at the time of Advanced Server installation use operating system user enterprisedb for Oracle compatible configuration mode and use postgres for PostgreSQL compatible configuration mode S su enterprisedb Password etc init d edb xdbpubserver restart Publication Service stopped Password Publication Service started Enter the password for the operating system user name when prompted If
391. te Publication The Create Publication dialog box appears Step 2 Fill in the following fields under the Create Publication tab e Publication Name Entera name that is unique amongst all publications e Publish Check the boxes next to the tables that are to be included in the publication e Select All Check this box if you want to include all tables in the Available Tables list in the publication Copyright 2012 EnterpriseDB Corporation All rights reserved 186 Postgres Plus xDB Replication Server with Multi Master User s Guide Figure 115 Create Publication dialog box If you wish to change the conflict resolution options from their default settings follow the directions in the next step otherwise go on to Step 4 Step 3 Optional If you want to modify or see the current conflict resolution options click the Conflict Resolution Options tab For each table you can select the primary conflict resolution strategy and a standby strategy by clicking the primary mouse button over the appropriate box to expose a drop down list of choices Copyright 2012 EnterpriseDB Corporation All rights reserved 187 Postgres Plus xDB Replication Server with Multi Master User s Guide Create Publication Conflict Resolution Options Table Conflict Resolution Strategy Standby Conflict Resolution Strategy edb dept Earliest Timestamp Manual Create Cancel Figure 116 Conf
392. ted The following sections provide additional detail on the server configuration options 9 3 1 1 Controlling Logging Level Note The option described in this section applies to the publication server and the subscription server Set the Logging level option to control the severity of messages written to the publication server log file and the subscription server log file see Section 9 2 2 4 logging level OFF SEVERE WARNING INFO CONFIG FINE FINER FINEST ALL The default value is SEVERE 9 3 1 2 Replacing Null Characters Note The options described in this section apply to the publication server only A character consisting of binary zeros also called the null character string and represented as 000 in octal or 0x00 in hexadecimal can result in errors when attempting to load such data into a Postgres character column You may get the following error in the Migration Toolkit log file when performing a snapshot replication of an Oracle table that contains the null character string Loading Table Data in 8 MB batches Balsiellollijaey INK Constreilnts Criggercs om eCo mull CesT losis TCEUICaTSan o Truncatingi cable INUilinih ARASH levsutonctes Clete ioaad Disa leincusindexcsonmed gt ymimllnTe Si berorrec dalam Oca char Loading Table NULL TEST Error Loading Data into Table NULL TEST ERROR invalid byte sequence for encoding AU
393. ted database objects When creating the subscription database definition the subscription database user name is entered in the Subscription Service Add Database dialog box see Section 5 3 2 CREATE USER subuser IDENTIFIED BY password GRANT CONNECT TO subuser Step 3 Grant the privileges needed to create the replicated database objects The replicated database objects are created in the schema owned by and with the same name as the subscription database user GRANT RESOURCE TO subuser 5 1 3 3 SQL Server Subscription Database Step 1 Create or choose the subscription database The names of the schemas containing the publication tables and views become the names of the SQL Server schemas for the subscription tables The subscription server creates these schemas in the subscription database when the subscription is created If schemas with these names already exist in the subscription database the existing schemas will be used to store the subscription tables Note If the schema containing the publication tables and views is named public then the subscription server creates a schema named public sql in the SQL Server subscription database for the subscription tables The existing schemas must not contain any tables or views with the same names as the publication tables and views The subscription server returns an error if there are already identically named tables or views You must delet
394. tem Copyright 2012 EnterpriseDB Corporation All rights reserved 359 Postgres Plus xDB Replication Server with Multi Master User s Guide Synopsis dosynchronize subname pubname repsvrfile subsvrfile pubsvrfile repgrouptype s m For a single master replication system use dosynchronize subname repsvrfile subsvrfile For a multi master replication system use dosynchronize pubname repsvrfile pubsvrfile repgrouptype m Note The dosynchronize command can be used on a subscription without first having to perform a snapshot using the dosnapshot command The dosynchronize command automatically performs the first required snapshot See Section 5 4 2 for additional information on performing synchronization replication for a single master replication system See Section 6 5 2 for a multi master replication system Parameters subname For SMR only The name of the subscription for which synchronization replication is to be performed pubname For MMR only The name of the publication for which synchronization replication is to be performed subsvrfile For SMR only The file containing the subscription server login information pubsvrfile For MMR only The file containing the publication server login information repgrouptype Specify s if this command applies to a single master replication system Specify m if this command applies to a multi master replication system If omitted the default is s
395. tem A publication in a Postgres master definition node contains tables from two schemas that are initially replicated to two other Postgres master nodes The tables in all three master nodes can then be updated and synchronized with each other Copyright 2012 EnterpriseDB Corporation All rights reserved 47 Postgres Plus xDB Replication Server with Multi Master User s Guide res multi master replication system xDB Replication Console or xDB Replication Server CLI DB Replication Server Schema g _edb_replicator_pub Figure 19 Postgres multi master replication system The following describes the logical components in the preceding diagram e The publication server to be used is identified by registering its network location user name and password e A publication database definition is created subordinate to the MMR type node under the publication server This first publication database definition identifies the master definition node The Postgres database user name mmruser_a is specified in the definition along with the database network location and database identifier The publication server creates schema edb replicator pub and populates it with database objects for the replication system s metadata when you create the publication database definition Copyright 2012 EnterpriseDB Corporation All rights reserved 48 Postgres Plus xDB Replication Server with Multi Master User s Guide e A publication named pub
396. tem during publication server installation The first step in creating a publication is to identify the publication server that is to be used to manage the publication This process is called registering the publication server Using the xDB Replication Console or the xDB Replication Server CLI a publication server is registered by giving the IP address and port number of the host on which the publication server is running along with the user name and password stored in the xDB Replication Configuration file located on the host running the publication server This information is determined during the publication server installation process When viewed in the xDB Replication Console a registered publication server appears under the top level Replication Servers node in the replication tree All publication related logical components are created subordinate to a registered publication server and appear underneath it in the replication tree Section 5 2 1 gives directions for registering a publication server for a single master replication system See Section 6 2 1 for a multi master replication system 2 3 2 2 Replication System Type SMR MMR Subordinate to a registered publication server two nodes representing the replication system type appear One is identified by the label SMR for single master replication and the other has the label MMR for multi master replication If you are creating a single master replication system you proceed
397. ter is omitted then the j obt ype parameter and one of parameters realtime daily weekly monthly or cronexpr must be specified along with the subname and repsvrfile parameters If there is an existing schedule for subscription subname it will be replaced by the new schedule See Section 7 1 for additional information on creating a schedule Parameters subname Copyright 2012 EnterpriseDB Corporation All rights reserved 361 Postgres Plus xDB Replication Server with Multi Master User s Guide The name of the subscription for which a replication schedule is to be created subsvrfile The file containing the subscription server login information remove If the remove parameter is specified then any existing schedule is removed from the subscription If the remove parameter is not specified then a schedule is created for the subscription jobtype Specify s if the scheduled replication is to be done by snapshot Specify t if the scheduled replication is to be done by synchronization If the associated publication is a snapshot only publication then jobtype s must be used no of sec The number of seconds between scheduled replications This can be any integer greater than 0 hour The hour of the day based on a 24 hour clock This can be any integer from 0 to 2 3f minute The minute of the hour This can be any integer from 0 to 59 day of week The day of the week This can be any of the following values SUN MON
398. testing and comparing results in real time Replication can be employed in this use case and is frequently used in development and testing environments Copyright 2012 EnterpriseDB Corporation All rights reserved 13 Postgres Plus xDB Replication Server with Multi Master User s Guide 2 1 4 Migrating Data Similar to running in parallel is the situation where data may be migrated from one system to another in a sort of seeding operation Replication can be very effective in this situation by quickly copying data Some reasons to consider multi master replication include the following 2 1 5 Write Availability In single master replication only the master database is available for writes The slave databases are read only for applications If the replicated target databases must be available for write access as well multi master replication can be employed for the same use cases as outlined for single master replication but with the additional advantage of write access to the slaves 2 1 6 Write Scalability In write intensive applications multi master replication allows you to utilize multiple database servers on separate hosts to process write transactions independently of each other on their own master databases Changes can then be reconciled across master databases according to your chosen schedule 2 1 7 Localized Data Access In a geographically dispersed application local access to the database can be provided to
399. tgres Plus xDB Replication Server with Multi Master User s Guide Stack Builder 3 0 0 Please select the applications you would like to install A gt w Database Server VvV Registration required and trial products gt gt ernis eD8 Solution Pack Migration Toolkit v1 0 4 l PL Secure for PostgreSQL 9 1 v9 1 0 1 I Postgres Enterprise Manager Agent v2 0 1 1 l Postgres Enterprise Manager Client v2 0 1 1 I Postgres Enterprise Manager SQL Profiler Plugi Ui Figure 28 Stack Builder applications Copyright 2012 EnterpriseDB Corporation All rights reserved 68 Postgres Plus xDB Replication Server with Multi Master User s Guide Stack Builder 3 0 0 Please select the applications you would like to install Postgres Enterprise Manager Agent v2 0 1 1 I Postgres Enterprise Manager Client v2 0 1 1 I Postgres Enterprise Manager SQL Profiler Plugi I Postgres Enterprise Manager Server v2 0 1 1 I SQL Protect for PostgreSQL 9 1 v9 1 0 1 Update Monitor v1 0 1 ie xDB Replication Server v2 52 1 I EnterpriseDB Tuning Wizard for PostgreSQL v1 4 fae Replication Server is a replication engine for replicating between PostgreSQL Postgres Plus PR Cantar racla sand COI Caruar Figure 29 Solution Pack for PostgreSQL Step 6 For Advanced Server only In the Account Registration screen either enter your email address and password for your EnterpriseDB user account if you have one or click th
400. tgres Plus xDB Replication Server with Multi Master User s Guide The advantages of a single host replication system are the following e There is a performance advantage since there is no network over which to push replication data especially if large snapshots are involved e Configuration is much simpler When creating the replication system logical components the IP addresses of all components are the same The disadvantages of a single host replication system are the following e The replication system and the database servers all consume the resources of one machine which can adversely affect database application performance e The publication and subscription databases may be in different geographic locations thereby requiring multiple networked hosts e Your site may require the use of a dedicated host for the Oracle or SQL Server database server so xDB Replication Server could not reside on the same machine 2 4 5 2 Single Master Replication Distributed Hosts XDB Replication Server allows you to build a replication system with either or both of the publication database and the subscription database on separate hosts This is illustrated in the following diagram Copyright 2012 EnterpriseDB Corporation All rights reserved 60 Postgres Plus xDB Replication Server with Multi Master User s Guide Postgres Plus host xDB Replication Console or xDB Replication Server CLI Oracle host xDB Replication V of
401. th Multi Master User s Guide 9051 UserName enterprisedb Password _ Save login information Figure 184 Update Publication Server dialog box Step 3 Complete the fields in the dialog box according to your purpose for updating the server login file If the publication server now runs on a host with a different IP address or port number than what is shown in the dialog box enter the correct information You must also enter the user name and password saved in the xDB Replication Configuration file that resides on the host identified by the IP address you entered in the Host field Check the Save Login Information box if you want the new login information saved in the server login file otherwise leave the box unchecked in which case access to the publication server is available for the current session but subsequent sessions will require you to register the publication server again If you want to delete previously saved login information make sure the network location shown in the dialog box is still correct Re enter the user name and password saved in the xDB Replication Configuration file that resides on the host identified by the IP address in the Host field Leave the Save Login Information box unchecked Access to the publication server is available for this session but subsequent sessions will require you to register the publication server again If you want to save the current login informati
402. the publication server is not running run the edb xdbpubserver script with the start option as shown by the following S su enterprisedb Password etc init d edb xdbpubserver start Password Publication Service started For Windows only Open Control Panel Administrative Tools and then Services The publication server runs as a service named Publication Service Copyright 2012 EnterpriseDB Corporation All rights reserved 117 Postgres Plus xDB Replication Server with Multi Master User s Guide File Action View Help es MHB 0L Hm e n Si Services Local Q Publication Service for xDB Name e Description Status A Replication Server Publication Service for xDB Replication Server Provides da Started Sia N S Quality Windows Audio EE IPEE Quality Win Pausa the semea Sh Remote Access Auto Connection Manager Creates a co Restart the service Gh Remote Access Connection Manager Manages di Remote Desktop Configuration Remote Des Gisciigiton S Remote Desktop Services Allows user Provides data replication services Sh Remote Desktop Services UserMode Port Redirect Allows the r from Oracle tm to Postgres Plus and 54 Remote Procedure Call RPC The RPCSS Started vice versa h Remote Procedure Call RPC Locator In Windows Figure 62 Windows publication service Use the Start or Restart link for the service Step 2 Register the publication server Open the xDB Replicatio
403. the resulting pg_hba conf file appears as follows TYPE DATABASE USER CIDR ADDRESS METHOD local is for Unix domain socket connections only Copyright 2012 EnterpriseDB Corporation All rights reserved 181 Postgres Plus xDB Replication Server with Multi Master User s Guide local anni SLIL md5 IPv4 local connections host xdb enterprisedb 192 168 10 102 32 md5 host edb pubuser 192 168 10 102 32 md5 host all all 127 050 1 32 md5 IPv6 local connections host all all s3 LZE md5 In the preceding example the xDB Control database xdb and a master node database edb are running on the same database server For a master node using database name mmrnode with database user name mmruser running on a separate host than where the xDB Control database is running the pg_hba conf file on this database server would look like the following TYPE DATABASE USER CIDR ADDRESS METHOD local is for Unix domain socket connections only Vocal anni SILIL md5 IPv4 local connections host mmrnode mmruser I 168 10 102 32 md5 host all all TT O0 T2 md5 IPv6 local connections host all all eo il lets md5 Reload the configuration file after making the modifications Choose Reload Configuration Expert Configuration then Reload Configuration on Advanced Server from the Postgres application menu This will put the modified pg_hba conf file into effect 6 2 Creating a Publication
404. the second case you do not select this option e The table rows in a master node can be reloaded from the master definition node The master node tables are truncated and the rows reloaded by a snapshot from the master definition node Once the multi master replication system is defined changes inserts updates and deletions to rows of the publication tables on any master node are synchronized to all other master nodes on either an on demand or scheduled basis Generally changes must not be made to the table definitions in any of the master nodes including the master definition node If such changes are made they are not propagated to other nodes in the multi master replication system unless they are made using the DDL change replication feature described in Section 7 6 If changes are made to tables without using the DDL change replication feature there is a risk that future replication attempts may fail Copyright 2012 EnterpriseDB Corporation All rights reserved 21 Postgres Plus xDB Replication Server with Multi Master User s Guide Master Node Master Node Figure 7 In a multi master replication system table rows can be updated at any master node 2 2 5 Asynchronous xDB Replication Server performs replications asynchronously The systems hosting the databases do not always have to be running continuously in order for successful replication to occur If one system goes offline replication resumes when it comes back onl
405. the source tables The database system s truncate operation is used to delete all rows from the target tables For Oracle and SQL Server only Oracle and SQL Server target tables are loaded using JDBC batches of INSERT statements For Postgres only In general Postgres target tables are loaded using the JDBC copy command since using truncation and COPY is generally faster than if you were to execute an SQL DELETE statement against the entire table and then add the rows using JDBC batches of INSERT statements If the COPY command fails the publication server retries the snapshot using JDBC batches of INSERT statements If the target table regardless of database type contains a large object data type such as BYTEA BLOB or CLOB then rows are loaded one at a time per batch using an INSERT statement This is to avoid a heap space error resulting from potentially large rows Loading time can be decreased by allowing multiple inserts per batch which is done by adjusting the configuration option lobBatchSize described in Section 5 8 1 Note Advanced Server supports a number of aliases for data types Such aliases that translate to BYTEA are treated as large object data types See the Oracle Compatibility Developer s Guide for a listing of Advanced Server data types Under certain circumstances the corresponding Postgres target table created for ce
406. the types of transactions affecting the publication See Section 5 8 2 for details on these particular options e Utilize alternate loading methods in snapshot replications See Section 5 8 1 for details on these particular options Copyright 2012 EnterpriseDB Corporation All rights reserved 395 Postgres Plus xDB Replication Server with Multi Master User s Guide e Special configuration options for multi master replication See Section 6 10 for details on these particular options e Adjust memory usage and transaction size for replications e Replicate certain Oracle partitioned table types e Replicate special characters found in publication data Most options apply to the publication server only although a few are used by the subscription server The configuration options for the publication server are set and passed in a text file called the publication server configuration file with file name xdb_pubserver conf The configuration options for the subscription server are set and passed in a text file called the subscription server configuration file with file name xdb_subserver conf See Section 3 2 for the directory locations of these files Modified publication server configuration options take effect after the publication server is restarted Similarly modified subscription server configuration options take effect after the subscription server is restarted The configuration options that have been explicitly put int
407. ti Master User s Guide e Make sure table definitions are well established before creating publications Unless the DDL change replication feature is used as described in Section 7 6 if a table definition is changed any publication containing the table along with its associated subscription must be deleted and recreated otherwise replication may fail The same applies for the table definitions in a master definition node and its associated master nodes Replication failures can be seen in the replication history e Views can be members of snapshot only publications In the subscription database a view is replicated as a table e A publication may have multiple subscriptions e A subscription can be associated with at most one publication e A database can contain both publications and subscriptions e A given publication server can support only one multi master replication system All master nodes created subordinate to a given publication server are assumed to be part of the same multi master replication system e A table that is created as a result of a subscription can be used in another publication Thus a publication can replicate data to a subscription which in turn can be used in a publication to replicate to another subscription thus creating a cascaded replication architecture e There are restrictions on the combinations and configurations of database servers that can be used for a publication and its subscription See Section 9 1
408. ti master replication system Examples In the following example the Oracle publication database definition identified by publication database ID 1 is validated Copyright 2012 EnterpriseDB Corporation All rights reserved 346 Postgres Plus xDB Replication Server with Multi Master User s Guide java jar edb repcli jar validatepubs gt repsvrfile pubsvrfile prop gt pubdbid 1 repgrouptype s Validating all available publications The schema definitions for all the non snapshot only publications tables are ain Syne with the source The validatepubs feature is not available for the following snapshot only publications salesemp 8 3 24 Removing a Publication removepub The removepub command removes one or more publications Synopsis removepub pubname_1 pubname 2 repsvrfile pubsvrfile repgrouptype m s See Section 7 5 5 for additional information on removing a publication Parameters pubname n The name of a publication to be removed pubsvrfile The file containing the publication server login information repgrouptype Specify s if this command applies to a single master replication system Specify m if this command applies to a multi master replication system Examples A publication named dept __emp is removed from a single master replication system java jar edb repcli jar removepub dept_emp gt repsvrfile pubsvrfile prop repgrouptype s Removing publication P
409. tion Database When you create a subscription database definition you save the subscription database server s network location IP address and port number the database identifier a database login user name and the user s password in the xDB Control database used by the subscription server This login information is used whenever a session needs to be established with the subscription database See Section 5 3 2 for information on creating a subscription database definition The steps described in this section show you how to update the subscription database login information stored in the xDB Control database should any of these attributes of the actual physical database change Note Depending upon the database type Oracle SQL Server or Postgres certain attributes must not be changed If you have already added subscriptions you must not change any attribute that alters access to the schema where the subscription tables were created Attributes you must not change if there are existing subscriptions include the following e The Oracle login user name as the subscription tables already reside in this Oracle user s schema Copyright 2012 EnterpriseDB Corporation All rights reserved 151 Postgres Plus xDB Replication Server with Multi Master User s Guide e The database server network location if the new network location references a database server that does not access the database that already contains the subscription ta
410. tion node From the Publication menu choose Publication Database and then choose Add Database Alternatively click the secondary mouse button on the MMR type node and choose Add Database The Publication Service Add Database dialog box appears Step 3 Fill in the following fields Copyright 2012 EnterpriseDB Corporation All rights reserved 190 Postgres Plus xDB Replication Server with Multi Master User s Guide e Database Type Currently Postgres Plus Advanced Server is the only available option e Host IP address of the host on which the master node is running e Port Port on which the master node is listening for connections e User The database user name for the master node created in Step 1 of Section e Password Password of the database user e Database Enter the database name of the master node e Node Priority Level An integer from 1 to 10 which is the priority level assigned to this master node for conflict resolution based on node priority The highest priority is 1 while the lowest is 10 See Section 6 6 3 for information on conflict resolution strategies As each additional master node is added the default priority level number increases assigning a lower priority level to each additional node e Replicate Publication Schema Check this box if you want the publication server to create the publication table definitions in the new master node by copying the definitions from the master definition node If you do n
411. tion system If omitted the default is s Examples In the following example the schedule is printed for a subscription in a single master replication system java jar edb repcli jar printschedule dept _emp sub gt repsvrfile subsvrfile prop printing subseription schedule Job type Synchronize Scheduled time ZAZA INS sss 237 3 20 Previous fire time AVIZ OG 19 153271320 Next fire time AVIZ OG 19 13532320 Copyright 2012 EnterpriseDB Corporation All rights reserved 366 Postgres Plus xDB Replication Server with Multi Master User s Guide In the following example the schedule is printed for a publication in a multi master replication system Note that the repgrouptype m parameter is required in this case java jar edb repcli jar printschedule emp pub gt repsvrfile pubsvrfile prop gt repgroupLlype Mm Printing subscription schedule Job type Synchronize Scheduled time 2012 06 19 Ise 27255 Previous fire time Not available Next fire time 2020 20 0800300 Cron expression Oeo A aR 8 3 39 Updating a Subscription updatesub For SMR only The updatesub command allows you to update certain metadata of a given subscription This metadata allows the subscription server to find the host running the publication server that manages the publication associated with the subscription Synopsis updatesub subname subsvrfile subsvrfile pubsvrfile pubsvrfile host newpubsvr ipaddress port newpu
412. tions that have not already been subscribed to 5 3 1 Registering a Subscription Server When you register a subscription server you are identifying the network location user name and password of a specific running subscription server instance that you want to use to manage all aspects of the subscriptions you will be creating subordinate to it It is important that you record the login information for the subscription server as you must always use this same subscription server instance to manage all subscriptions created subordinate to it as represented in the xDB Replication Console replication tree Step 1 Start the subscription server if it is not already running Repeat the same process as in Step 1 of Section 5 2 1 Note If you are using Oracle publication or subscription databases and the subscription server has not been restarted since copying the Oracle JDBC driver ojdbc14 jar to the 1ib jdbc subdirectory of your xDB Replication Server installation you must restart the subscription server For Linux only Use script etc init d edb xdbsubserver to restart or start the subscription server Run the script as the operating system user that you chose during installation in the Publication Subscription Service Account screen in Step 18 of Section 3 1 This is illustrated by the following ps aux grep subserver 502 5290 Ooi 2o8 AMOSA SIs z Sil LS SS ORON opt PostgresPlus 9 1AS jre bin java Djava awt headless true
413. tively small amounts of data you can increase the speed of a snapshot replication by increasing the value of the LlobBatchSize option to allow a greater number of rows specified by n in each batch lobBatchSize n The default value is 1 Copyright 2012 EnterpriseDB Corporation All rights reserved 169 Postgres Plus xDB Replication Server with Multi Master User s Guide 5 8 2 Optimizing Synchronization Replication This section discusses configuration options for improving synchronization replication performance Note The options described in this section apply to the publication server only and are set in the publication server configuration file 5 8 2 1 Using Prepared SQL Statements When synchronization replication occurs the changes recorded in the shadow tables are applied to the subscription tables in JDBC batch updates Within each batch changes may be applied using either an individual SQL statement for each change or a set of changes may be applied using a single prepared SQL statement A prepared SQL statement is parsed and compiled only once but it can be executed multiple times using different values for certain components of the SQL statement in each execution A SQL statement that is not prepared is parsed compiled and executed only once Prepared statements are useful only if the same type of SQL statement INSERT UPDATE or DELETE is executed repeatedly and consecutively with the same target tab
414. to edb il 2 gt SELECT s name o name Trigger Name 3S FROM sys objects o 4 gt sys schemas s ey WHERE s name edb 6 gt AND o type TR T AND o name LIKE rr 8 gt AND schema_ id s schema_id 9 gt ORD Ears YE 10 gt GO Trigger Name edb edb edb edb edb edb rrpd_edb dept rrpd_edb_emp Toot eclo Cept rrpi_edb_ emp ana ob Kel ome l johe rrpu_edb_ emp 6 rows affected Finally some jobs are created in the msdb database as shown by the following 1 gt USE msdb 2 GO Changed database context to msdb i gt 2 gt SELECT j name Job Name 35 FROM msdb dbo sysjobs j 4 gt master dbo syslogins 1 5 gt WHERE l name pubuser 6 gt AND j name LIKE rrep 71 gt JNINID 5 oermnere issavel IL asa 8 gt ORD E Rass YEE 9 gt GO Job Name mrepecloanup Edy Obmeds ee PEEKS Clem OOMme Cy 2 rows affected Postgres only The metadata database objects to manage the publication are created in the schema edb replicator pub as shown in the following Copyright 2012 EnterpriseDB Corporation All rights reserved 389 Postgres Plus xDB Replication Server with Multi Master User s Guide Postgres En SLE File Edit gc View Management Tools Help coRE BEY Eq0O Object browser E Databases 3 x i F Properties X Statistics Dependencies Depende 0 edb Property Value hx
415. to add logical components under the SMR type node If you are creating a multi master replication system you proceed to add logical components under the MMR type node 2 3 2 3 Publication Database Definition Subordinate to one of the Replication System Type nodes under a registered publication server one or more publication database definitions can be created A publication database definition identifies a database whose tables and views are to be used in a publication The identify information consists of the database server IP address port number a database user name and password and the database identifier The publication server uses this information to connect to the publication database in order to create the replication system metadata in the publication database and perform the replications Copyright 2012 EnterpriseDB Corporation All rights reserved 34 Postgres Plus xDB Replication Server with Multi Master User s Guide Though the process of creating a publication database definition is similar for single master and multi master replication systems their usage within the replication system is somewhat different In a single master replication system a publication database definition identifies the storage area of one or more publications each of which is eventually associated with its own subscription in a master to slave relationship In a multi master replication system each publication database definition su
416. to nodes A and C e Finally the master node C changes are replicated to nodes A and B 6 6 3 Conflict Resolution Strategies A number of built in conflict resolution options are available to support automatic conflict resolution The conflict resolution options are applicable to update update and delete delete conflicts Uniqueness update delete and delete update conflicts are marked unresolved and must be manually reconciled The following are the built in conflict resolution options e Earliest Timestamp When the earliest timestamp option is selected the relevant rows involved in an update conflict from the source and target master nodes are compared based on the timestamp of when the update occurred on that particular node The row change that occurred earliest is applied The row changes with the later timestamps are discarded e Latest Timestamp Same approach as earliest timestamp except the row change with the latest timestamp is accepted The row changes with earlier timestamps are discarded e Node Priority The row change of the master node with the highest node priority level is applied while the lower priority level master node changes are discarded The node priority level is an integer in the range of 1 to 10 inclusive where 1 is the highest priority level and 10 is the lowest priority level The delete delete conflict is always resolved implicitly regardless of the conflict resolution option in effect The net impact of
417. to the publication table definitions you can either 1 update the table definitions on all master nodes so that they are identical or 2 assume the table definitions on the master definition node are up to date and delete the out of date table definitions on all other master nodes e Re add the publication database definition for the master definition node See Section 6 2 2 for directions to add the master definition node e Re add the publication See Section 6 2 3 for directions to add a publication e Re add additional master nodes See Section 6 3 for directions to add an additional master node When creating a master node uncheck the Replicate Publication Schema check box if you have already created the table definitions on all master nodes Check the Replicate Publication Schema check box if you want to propagate the table definitions from the master definition node to all other master nodes A snapshot reloads the master node tables from the master definition node 7 5 4 1 Validating a Single Publication xDB Replication Server provides a way to verify that certain characteristics of publication tables have not been altered since the publication was created The validation operation described here and in Section 7 5 4 2 can check for the following types of table modifications e Addition of columns to a table e Removal of columns from a table e Renaming of columns Note In a multi master replication system publication tables
418. to the source tables is growing at a faster rate than usual and you do not want to wait for the regularly scheduled synchronization time to replicate all of the accumulated changes e You have set up your replication system to perform synchronizations but on this occasion there have been an unusually large number of changes made to the source tables and you would rather perform a snapshot of all source tables rather than execute a large number of SQL statements against the target tables e Changes have been made directly to the rows of the target tables so that they no longer have the same content as their source table counterparts You can perform an on demand snapshot replication to reload all rows of the target tables from your current set of source tables Note In a multi master replication system on demand snapshots can only be made from the master definition node to another master node See Section 5 4 for directions on performing an on demand replication for a single master replication system See Section 6 5 for a multi master replication system 2 4 5 Distributed Replication xDB Replication Server provides the flexibility of allowing you to run the replication system s components on separate machines on a network In fact xDB Replication Server is designed so that it is possible to set up replication systems where each of the components publication server subscription server xDB Control database publication database subscri
419. tree you should see the following Copyright 2012 EnterpriseDB Corporation All rights reserved 394 Postgres Plus xDB Replication Server with Multi Master User s Guide ts Replication Servers ee e Publication Server 192 168 2 3 9051 2 MMR FA SMR General Realtime Monitor Replication H Service status Subscription Server 192 168 2 3 9052 Authentication Subscription database count Figure 232 Replication tree after removal of all metadata database objects All the nodes under the SMR and MMR type nodes beneath the Publication Server node and under the Subscription Server node no longer appear as the metadata has been deleted Step 11 You will need to recreate the replication system as described in sections 5 2 onward for a single master replication system See sections 6 2 onward for a multi master replication system 9 3 Miscellaneous xDB Replication Server Processing Topics This section contains various topics covering the following Handling special characters in replication data Replicating Oracle partitioned tables Performing an offline snapshot and subsequent synchronization Generating an encrypted password Writing cron expressions 9 3 1 Publication and Subscription Server Configuration Options The publication server and the subscription server support various configuration options for purposes such as the following e Optimize synchronization performance based on
420. trigger name FROM user triggers Copyright 2012 EnterpriseDB Corporation All rights reserved 127 Postgres Plus xDB Replication Server with Multi Master User s Guide TRIGGER_NAME RRPI_EDB_DEPT RRPU_EDB_ DEPT RRPD_EDB DEPT RRPI EDB EMP RRPU EDB EMP RRPD EDB EMP 6 rows selected For SQL Server only Most of the metadata database objects are created in the schema you chose in Step 5 of Section 5 1 2 2 as shown by the following 1 gt USE edb Ze GO Changed database context to edb i gt 2S SIMIC S pene T Yo a Oo meme Object Nene Cpe Cese Wooject yes 35 FROM sys objects o 4 gt sys schemas s 5 gt WHERE s name pubuser 6 gt ANDY oO ype IN TUL EI T gt ANDRO Rc chemameicle a Sric clenamsncl 8 gt ORDERIE Vane mma VS EO Object Name Object Type pubuser CleanupShadowTables SQL STORED PROCEDURE pubuser ConfigureCleanUpJob SQL STORED PROCEDURE pubuser ConfigureCreateTxSetJob SQL STORED PROCEDURE pubuser CreateMultiTxSet SQL STORED PROCEDURE pubuser CreateTableLogTrigger SQL STORED PROCEDURE pubuser CreateTxSet SQL STORED PROCEDURE pubuser CreateUniTxSet SQL STORED PROCEDURE pubuser GetNewTxs
421. ts reserved 50 Postgres Plus xDB Replication Server with Multi Master User s Guide from a Postgres Plus Advanced Server database to an Oracle database or from a PostgreSQL or Advanced Server database to a SQL Server database Step 2 Plan the general strategy of how you will use xDB Replication Server Will the single master or multi master model best suit your needs See Section 2 1 for use case examples of single master and multi master replication systems Will you be replicating from Oracle to Postgres from SQL Server to Postgres from Advanced Server to Oracle or from Postgres to SQL Server Will you be replicating between PostgreSQL and or Advanced Server databases How often will you need to replicate the data Will replication be done on an ad hoc basis or does it need to occur regularly according to a schedule Step 3 Plan the logistics of your replication system How many tables do you expect to replicate and what are their sizes in total number of bytes and number of rows What percentage of rows do you expect to have been changed on each table between each replication Are your database servers required to run on dedicated machines Step 4 Design your replication system Determine whether your replication system will be distributed or will run on a single host Determine the publications and subscriptions you will need and their tables and views Make sure your publication tables meet the requirements for an xDB Replication Ser
422. ty et Postgres Plus Advanced Server 192 Host 192 168 2 7 Port 5444 Database subdb User subuser Figure 97 Selecting a subscription database definition for update Copyright 2012 EnterpriseDB Corporation All rights reserved 152 Postgres Plus xDB Replication Server with Multi Master User s Guide Step 4 From the Subscription menu choose Subscription Database and then choose Update Database Alternatively click the secondary mouse button on the Subscription Database node and choose Update Database The Update Database Source dialog box appears Step 5 Enter the desired changes See Step 3 of Section 5 3 2 for the precise meanings of the fields Figure 98 Update Database Source dialog box Step 6 Click the Test button If Test Result Success appears click the OK button then click the Save button Copyright 2012 EnterpriseDB Corporation All rights reserved 153 Postgres Plus xDB Replication Server with Multi Master User s Guide Update Database Source Figure 99 Successful subscription database test If an error message appears investigate the cause of the error correct the problem and repeat steps 1 through 6 Step 7 Click the Refresh icon in the xDB Replication Console tool bar to show the updated Subscription Database node and any of its subscriptions td Replication Servers H Publication Server 192 168 2 7 9051 g Subscription Server 192 168 2 7 9052 Postgres Plus Advan
423. typically be used following the order in which xDB Replication Console operations are performed Note Though most commands described in this section apply to both single master and multi master replication systems those commands that apply only to single master replication systems are noted with For SMR only Those commands that apply only to multi master replication systems are noted with For MMR only The same notation is used for command parameters that may apply only to single master replication systems or multi master replication systems For the examples used in this section it is assumed that the xDB Replication Server CLI commands are executed after you have made XDB_HOME bin your current working directory thereby eliminating the need to specify the full path of XDB_HOME bin for each execution of the edb repcli jar file For example assuming xDB Replication Server is installed in your Postgres installation directory that is XDB_ HOME is the same directory as POSTGRES INSTALL HOME you have issued the following command in Linux cd opt PostgresPlus 9 1AS bin In Windows the equivalent is the following cd C Program Files PostgresPlus 9 1AS bin Whenever the repsvrfile parameter appears in the examples file pubsvrfile contains the publication server login information and is located in the user s home directory while subsvrfile contains the subscription server login information The examples in this section were run on Li
424. ublication dept_emp unpublished successfully Copyright 2012 EnterpriseDB Corporation All rights reserved 347 Postgres Plus xDB Replication Server with Multi Master User s Guide 8 3 25 Replicating DDL Changes replicateddl The replicateddl command applies an ALTER TABLE statement to a publication table in all databases of a replication system as well as updates the xDB Replication Server insert update delete triggers and shadow table associated with that publication table Synopsis replicateddl pubname repsvrfile pubsvrfile table schema t table name ddlscriptfile script file See Section 7 6 for additional information on DDL change replication Parameters pubname The name of the publication containing the table to which the ALTER TABLE statement is to be applied pubsvrfile The file containing the publication server login information schema t The name of the schema containing table name This value is case sensitive table name The name of the table in the ALTER TABLE statement whose definition is to be modified This value is case sensitive script file Path to the file containing the ALTER TABI E statement Examples The following example shows the addition of a column named title to table edb emp The ALTER TABLE statement is in the text file addcolumn sql as shown by the following ALTER TABLE edb emp ADD COLUMN t
425. ublications replicated to the database identified by the subscription database definition You must enter database connection information such as the database server network address database identifier and database login user name and password when you create the subscription database definition The connection information is used by the subscription server to create the subscription table definitions and by the publication server to perform replications Note the following restriction on the subscription database e For Oracle only There must be no existing tables or views owned by the Oracle subscription database user that has the same name as a table or view in a publication that will be replicated to this database For example if the Oracle subscription database user name is subuser and if a Postgres publication contains a table with the name dept then the Oracle subscription database must not have an existing table or view with the schema qualified name subuser dept at the time you create the subscription e For Postgres only There must be no existing tables or views with the same schema qualified name as a table or view in a publication that will be replicated to this database For example if the publication contains a table with the schema qualified name edb dept then the Postgres subscription database must not have an existing table or view with the schema qualified name edb dept at the time you create the subscription Note If t
426. ubsvrfile The output has the following components dbid host port dbname user Note The database user s password is not displayed Parameters Copyright 2012 EnterpriseDB Corporation All rights reserved 325 Postgres Plus xDB Replication Server with Multi Master User s Guide pubsvrfile The file containing the publication server login information dbid The publication database ID assigned to the publication database definition host The IP address of the host on which the publication database server is running port The port number on which the database server is listening for connections dbname The Postgres or SQL Server database name the Oracle SID or the Oracle service name of the publication database user The publication database user name Examples There are four publication database definitions subordinate to the publication server identified by the content of file pubsvrfile prop java jar edb repcli jar printpubdbidsdetails gt repsvrfile pubsvrfile prop Printing publication database ids with details id host port database sid user 6 192 168 2 6 5444 edb pubuser 9 192 168 2 7 5444 mmrnode mmruser 2 192 168 2 7 5444 edb pubuser eA WS Boel Ail Eke pU DUSE 8 3 8 Updating a Publication Database updatepubdb The updatepubdb command provides the ability to change the connection information for an existing publication database definition identified by its publication database ID S
427. uent replications can be done using either the synchronization method if the publication was not initially defined as a snapshot only publication or the snapshot method Step 1 Select the Subscription node of the subscription for which you wish to perform snapshot replication S ITE BOL ee ta Replication Servers E E Publication Server 192 168 2 7 9051 Subscription Server 192 168 2 7 9052 Postgres Plus Advanced Server 192 Publication server eg SE Publication server port B B sales_dept Scheduled job status EDB DEPT H E EDB EMP Figure 86 Selecting a subscription for an on demand snapshot Step 2 Open the Snapshot dialog box in any of the following ways e From the Subscription menu choose Snapshot e Click the secondary mouse button on the Subscription node and choose Snapshot e Click the primary mouse button on the Snapshot icon Copyright 2012 EnterpriseDB Corporation All rights reserved 142 Postgres Plus xDB Replication Server with Multi Master User s Guide 4 Replication Servers Publication Server 192 168 2 7 9051 S E Subscription Server 192 168 2 7 9052 GP Postgres Plus Advanced Server 192 Se BEES aes te sales_deq Snapshot H E EDB E Figure 87 Opening the Snapshot dialog box Step 3 Click the Snapshot button to start snapshot replication Copyright 2012 EnterpriseDB Corporation All rights reserved 143 Postgres Plus xDB Replication Server with Multi M
428. uild number The specific location of POSTGRES_ HOME is dependent upon your version of Windows Copyright 2012 EnterpriseDB Corporation All rights reserved 381 Postgres Plus xDB Replication Server with Multi Master User s Guide Note The severity level of messages logged in these files can be controlled by a configuration option See Section 9 3 1 1 Also check the database server log file 9 2 2 5 Database Server Errors Check the database server log file The typical default location of these files is POSTGRES INSTALL HOME data pg_log 9 2 2 6 Oracle Errors For problems in Oracle first find the directory locations of the log files by issuing the following commands in SQL Plus SQL gt SHOW PARAMETER USER DUMP DEST NAME TYPE VALUE user dump dest string usr lib oracle xe app oracle admin XE udump The directory given by parameter USER_DUMP_DEST contains errors given by user processes SQL gt CONNECT system password Connected SQL gt SHOW PARAMETER BACKGROUND DUMP DEST NAME TYPER VALUE background dump dest string ausr lib oracle xe app oracle admin XE bdump The directory given by parameter BACKGROUND DUMP DEST contains errors given by the Oracle background processes Find the latest log file in the preceding directories to investigate the problem 9 2 3 Common Problem Checklist Use the following checklist to verify that the proper configuration steps have been followed Omission of one or m
429. un on a separate networked host When the publication server is started it uses the information in the xDB Replication Configuration file found on its host to connect to the xDB Control database 2 3 1 2 Subscription Server Note The subscription server is required only for single master replication systems The subscription server does not need to be running nor even installed if only multi master replication systems are in use The subscription server creates and manages the metadata for subscriptions When a subscription is created the subscription server creates database objects in the xDB Control database to record metadata about the subscription When a subscription is created the subscription server calls EnterpriseDB s Migration Toolkit to create the subscription table definitions in the subscription database The rows in the subscription tables are not populated until a replication occurs Rows are populated by actions of the publication server The subscription server is also responsible for initiating a replication as a result of manual user action through the user interface or a schedule created for the subscription The subscription server initiates a call to the publication server that manages the associated publication The publication server then performs the actual replication The subscription server may run on the same host as the other xDB Replication Server components or it may run on a separate networked host
430. update trigger and a delete trigger on each publication table In a multi master replication system each replicated table in every master node has an insert trigger an update trigger and a delete trigger The publication server also creates a shadow table for each source table A shadow table is a table used by xDB Replication Server to record the changes inserts updates and deletions made to a given source table A shadow table records three types of record images For each row inserted into the source table the shadow table records the image of the inserted row For each existing row that is updated in the source table the shadow table records the after image of the updated row For each row deleted from the source table the shadow table records the primary key value of the deleted row Note In a multi master replication system the before image of an updated row is also stored in the shadow table in order to perform update conflict detection See Section 6 6 for information on conflict detection in a multi master replication system After each change on the source table one of the insert update or delete triggers is executed These are row triggers so for each row affected by the change the trigger executes Each execution of the trigger records a row of the appropriate type insert update or deletion in the shadow table of the corresponding source table When synchronization replication occurs the publication server executes
431. ur license key the registration status of your xDB Replication Server product is updated The following are the steps to enter your license key Step 1 A publication server must be registered and running under the xDB Replication Server installation for which you want to supply the license key See steps 1 through 3 of Section 5 2 1 for directions on starting and registering a publication server if you have not already done so Step 2 Select the Publication Server node From the Help menu choose Register xDB MMR The Product Registration dialog box appears Copyright 2012 EnterpriseDB Corporation All rights reserved 88 Postgres Plus xDB Replication Server with Multi Master User s Guide File Publication Subscription amp rs Cay R E Register xDB MMR tg Replication Servers eS Publication Server 192 16 Ba SMR 2 MMR Ublication Databases Property Service status Authentication Publication database count Figure 50 Opening the Product Registration dialog box Step 3 Enter your license key in the Product Registration dialog box and click the OK button r Product Registration A valid product key must be entered in order to use Postgres Plus xDB Replication Server application once the initial trial has ended Without a valid product key once the trial has ended you will not be able to use the core features in MMR replication mode Please contact EnterpriseDB to purchase a
432. uration mode is selected at the time you install Postgres Plus Advanced Server 9 1 2 Permitted Source and Target Configurations The following table shows the combinations of source and target database server products and Advanced Server compatibility configuration modes permitted by xDB Replication Server Copyright 2012 EnterpriseDB Corporation All rights reserved 374 Postgres Plus xDB Replication Server with Multi Master User s Guide Table 7 Permitted Source and Target Configurations Postgres Plus Microsoft sian Advanced Source Target Oracle SQL PostgreSQL Server Server Oracle Server compatible PostgreSQL compatible Oracle compatible a In the preceding table the left hand column lists the possible source database server products including the possible Advanced Server compatibility configuration modes The top row lists the same set of possible target database server products and Advanced Server compatibility configuration modes Yes at the intersection of a source and target indicates that xDB Replication Server permits replication using that combination of database server configurations for a publication and its associated subscription No indicates replication is not permitted for that combination 9 2 Resolving Problems This section contains tips for locating and correcting various problems that may occur 9 2 1 Error Messages The following table is a list of error messages that can appea
433. urs when attempting a snapshot replication The publication server running on host xxx xxx xx xxx Could not access the subscription database Verify that the pg hba conf file on the subscription database server permits access from the publication server host Unable to synchronize Reason FATAL no pg hba conf entry for host XXX XXX XX XXX user user name database db name SSL off Reason Occurs during an implicit synchronization following snapshot replication The publication server running on host xxx xxx xx xxx could not access the subscription server s xDB Control database Verify that the pg_hba conf file on the subscription server permits access from the publication server host using network address xxx xxX XX XXX Unable to update publication database information Reason Publication control schema does not exist on target database Resolution The metadata database objects in the publication database may have been deleted or corrupted For an Oracle publication database the metadata database objects are located in the publication database user s schema For a Postgres publication database the metadata database objects are located in schema edb replicator pub See Section 9 2 4 2 9 2 2 Where to Look for Errors There are a number of places to look to find more detailed information about a replication error that may have occurred This section provides a guide as to where to look for various types of errors 9 2 2 1
434. us xDB Replication Server with Multi Master User s Guide Specify sid if the Oracle system ID SID is used to identify the publication database in the database parameter Specify servicename if the Oracle service name is used to identify the publication database in the database parameter dbname The Postgres or SQL Server database name the Oracle SID or the Oracle service name of the publication database priority level For MMR only Integer value from 1 through 10 assigning the priority level to a master node with 1 having the highest priority and 10 having the lowest priority Examples In the following example an existing publication database definition with publication database ID 1 is updated java jar edb repcli jar updatepubdb repsvrfile pubsvrfile prop S pubdbid 1 gt qclonese 192 168 2515 selasore 152i gt dbuser pubuser dbpassfile pwdfile gt oraconnectiontype sid gt database xe Updating publication database Publication database with ID 1 is updated successfully 8 3 9 Removing a Publication Database removepubdb The removepubdb command removes a publication database definition Synopsis removepubdb repsvrfile pubsvrfile pubdbid dbid The publication database definition to be removed is identified by the pubdbid parameter See Section 7 5 6 for additional information on removing a publication database Parameters pubsvrfile The file containing the publication serve
435. use Step 4 Click the Create button If Publication Created Successfully appears click the OK button otherwise investigate the error and make the necessary corrections Copyright 2012 EnterpriseDB Corporation All rights reserved 125 Postgres Plus xDB Replication Server with Multi Master User s Guide Create Publication Create Publication Filter Clause Specify a filter criteria to exclude table rows from replication The filter criteria is a SQL WHERE CLAUSE without WHERE keyword For example state CA Table Type deptno 30 EDB EMP l deptno 30 Create Publication Q Publication created successfully Figure 72 Publication created successfully Upon successful publication creation a Publication node is added to the replication tree Fie Publication Subscription Help SOLO OLAT g Replication Servers lt General Realtime Monitor Replication History Conflict History amp Publication Server 192 168 2 7 9051 Be SMR Property les Oracle 192 168 2 6 1521 xe pubuser Publication schema EDB amp ty sales_dept Table count 2 ft EDB DEPT Subscription count 0 s EDB EMP amp 2 MMR Figure 73 Replication tree after adding a publication Copyright 2012 EnterpriseDB Corporation All rights reserved 126 Postgres Plus xDB Replication Server with Multi Master User s Guide 5 2 4 Metadata Created for a Publication After you ha
436. user name must have a password and it must have the ability to create a Copyright 2012 EnterpriseDB Corporation All rights reserved 101 Postgres Plus xDB Replication Server with Multi Master User s Guide database session The publication database user becomes the owner of xDB Replication Server metadata database objects that will be created in the publication database to track control and record the replication process and history When creating the publication database definition the publication database user name is entered in the Publication Service Add Database dialog box see Section 5 2 2 CREATE USER pubuser IDENTIFIED BY password GRANT CONNECT TO pubuser Step 2 Grant the privileges needed to create the xDB Replication Server metadata database objects The xDB Replication Server metadata database objects are created in the schema owned by and with the same name as the publication database user GRANT RESOURCE TO pubuser Step 3 Grant the privileges required to create triggers on the publication tables The CREATE ANY TRIGGER privilege must be granted to the publication database user GRANT CREATE ANY TRIGGER TO pubuser Step 4 The publication database user must be able to read the tables and views that are to be included in publications GRANT SELECT ON edb dept TO pubuser GRANT SELECT ON edb emp TO pubu
437. ve added a publication database definition and publications you will find the following database objects have been created e A schema named edb replicator pub is created in the xDB Control database with metadata database objects that are used to manage the publication e In the publication database several metadata database objects are created to control and manage the publication e If the publication is not a snapshot only publication that is synchronization replication is permitted then three triggers and one shadow table are created for each publication table For Oracle only The metadata database objects are created in the publication database user s schema as shown in the following output SQL gt CONNECT pubuser password Connected SQL gt SET PAGESIZE 9999 SQL gt SELECT table name FROM user tables TABLE NAME RREP TABLES RREP PUBLICATION TABLES RREP TXSET RREP R_TXSET RREP PUBLICATION SUBSCRIPTIONS RREP_TXSET_ LOG RREP LOCK RREP_ MMR PUB_GROUP RREP PROPERTIES RREP_ TXSET HEALTH RRST_EDB DEPT RRST EDB E 12 rows selected SQL gt SELECT sequence name FROM user sequences SQL gt SELECT DISTINCT name FROM user source WHERE type PACKAG EJ SQL gt SELECT
438. ver publication See sections 2 4 2 and 2 4 3 for details Step 5 Implement and test your replication system in a test environment Try out your replication system on a subset of your publication data to ensure the replication process works as expected Make sure the resulting replicated tables can be used as expected in your application Establish preliminary metrics on how long the replication process will be expected to take in your full production environment Step 6 Implement and test your replication system in your production environment 2 4 2 Design Considerations Keep the following points in mind when designing a replication system e Multi master replication is supported only on Postgres databases In addition Advanced Server databases must be running in the same compatibility mode either all Oracle or all PostgreSQL e An Oracle table can be a member of at most one publication if all publications are subordinate to one publication database definition However an Oracle table can be a member of multiple publications if each publication is subordinate to a different publication database definition e A Postgres table can be a member of at most one publication e Each table used in a publication must have a primary key with the exception of tables in snapshot only publications which do not require a primary key Copyright 2012 EnterpriseDB Corporation All rights reserved 51 Postgres Plus xDB Replication Server with Mul
439. vestigate the error and make the necessary corrections Step 6 If the publication server with the new network location manages publications subscribed to by other subscriptions repeat steps 1 through 5 for these other subscriptions 5 5 4 Removing a Subscription After a subscription is removed replication can no longer occur for the publication that was associated with it until the publication is subscribed to with a new subscription Removing a subscription does not delete the subscription tables in the subscription database It removes the identity and association of these tables to xDB Replication Server so the tables remain in the database until the DBA deletes them with DROP TABLE SQL statements Step 1 Make sure the subscription server whose node is the parent of the subscription you wish to remove is running and has been registered in the xDB Replication Console you are using See Section 5 3 1 for directions on starting and registering a subscription server Step 2 Select the Subscription node of the subscription that you wish to remove Copyright 2012 EnterpriseDB Corporation All rights reserved 157 Postgres Plus xDB Replication Server with Multi Master User s Guide bd Replication Servers He Publication Server 192 168 2 7 9051 eg Subscription Server 192 168 2 7 9052 Postgres Plus Advanced Server 192 Publication server E S Publication server port B F sales_dept Sc
440. w conflict history 6 6 Conflict Resolution There are certain situations where synchronization replication may result in data conflicts arising from the row changes that took place on different master nodes Conflict resolution deals with the topic of the types of conflicts that might occur the strategies for dealing with conflicts and the options available for automatically resolving such conflicts 6 6 1 Conflict Types The types of conflicts can be summarized as follows e Uniqueness Conflict A uniqueness conflict occurs when the same value is used for a primary key or unique column in an insert transaction on two or more master nodes This is also referred to as an insert insert conflict Copyright 2012 EnterpriseDB Corporation All rights reserved 203 Postgres Plus xDB Replication Server with Multi Master User s Guide e Update Conflict An update transaction modifies a column value in the same row on two or more master nodes For example an employee address column is updated on master node A and another user updates the address column for the same employee on master node B The timestamps of when the transactions occur on each node could be different but both transactions occur in a time interval during which synchronization has not yet occurred Thus when synchronization does take place both conflicting transactions are to be applied This is also referred to as an update update conflict e Delete Conflict The row corresp
441. w table history Step 4 Click the Yes button in the Cleanup Synchronization History confirmation box Copyright 2012 EnterpriseDB Corporation All rights reserved 249 Postgres Plus xDB Replication Server with Multi Master User s Guide QJ Subscription Server 192 168 2 7 9052 Figure 175 Cleanup Synchronization History confirmation Step 5 Click the Yes button in response to Shadow Table s Transaction History Removed Successfully Copyright 2012 EnterpriseDB Corporation All rights reserved 250 Postgres Plus xDB Replication Server with Multi Master User s Guide UBS Uw eyes g Replication Servers General Realtime Monitor Replication History Publication Server 192 168 2 7 9051 oo MMR E B SMR Publication schema g Oracle 192 168 2 6 1521 xe pubus Table count amp ty Subscription count H E EDB EMP h Subscription Server 192 168 2 7 9052 Shadow table s transaction history removed successfully Figure 176 Successful cleanup of shadow table history After shadow table history cleanup if you click the View Data link of the Replication History tab an information message appears stating that there is no synchronization history to view File Publication Subscription Help S BmwWy Tees 5 eS Publication Server 192 168 10 102 9051 amp Oracle 192 168 10 103 1521 xe pubus Type Synchronize w E aa 339
442. x is still correct Re enter the user name and password saved in the xDB Replication Configuration file that resides on the host identified by the IP address in the Host field Leave the Save Login Information box unchecked Access to the subscription server is available for this session but subsequent sessions will require you to register the subscription server again e If you want to save the current login information shown in the dialog box make sure the network location shown in the dialog box is correct Re enter the user name and password saved in the xDB Replication Configuration file that resides on the host identified by the IP address in the Host field Check the Save Login Information box Copyright 2012 EnterpriseDB Corporation All rights reserved 150 Postgres Plus xDB Replication Server with Multi Master User s Guide 192 168 2 8 Port 9052 UserName enterprisedb Password e80ee0 V Save login information Figure 96 Updated subscription server location Step 4 Click the Update button If the dialog box closes then the update to the server login file was successful Click the Refresh icon in the xDB Replication Console tool bar to show the updated Subscription Server node If an error message appears after clicking the Update button the server login file is not modified Investigate and correct the cause of the error Repeat steps 1 through 4 5 5 2 Updating a Subscrip
443. xample of an update conflict Copyright 2012 EnterpriseDB Corporation All rights reserved 204 Postgres Plus xDB Replication Server with Multi Master User s Guide Table 3 Update Conflict Timestamp Master Node A Master Node B 0 id 2 address id 2 address ADDR B ADDR B INode A UPDATE addrbook ET address ADDR B1 ERE id 2 B UPDATE addrbook address ADDR B2 ERE id 2 id 2 address id 2 address ADDR B1 ADDR B id 2 address id 2 address ADDR B1 ADDR B2 Current value of address on Synchronization pushes Node A Node B not equal old value changes to Node B on Node A ADDR B2 lt gt ADDR B The following table illustrates an example of a delete conflict Table 4 Delete Conflict Timestamp Master Node A Master Node B t0 id 2 address id 2 address ADDR B ADDR B Node A UPDATE addrbook ET address ADDR B1 id 2 id 2 address id 2 address ADDR B1 ADDR B id 2 address ADDR B1 Row with id 2 deleted The row with id 2 is Synchronization pushes Node A already deleted on target changes to Node B Node B hence update from Node A fails 6 6 2 Conflict Detection This section discusses the synchronization process and conflict detection When synchronization replication occurs either on demand or on a scheduled basis each of the maste
444. ynopsis updatepubdb repsvrfile pubsvrfile pubdbid dbid Copyright 2012 EnterpriseDB Corporation All rights reserved 326 Postgres Plus xDB Replication Server with Multi Master User s Guide dbhost host dbport port dbuser user dbpassword encrypted pwd dbpassfile pwdfile oraconnectiontype sid servicename database dbname nodepriority priority level The publication database definition to be updated is identified by the pubdbid parameter See Section 5 2 2 for details on the database connection information that must be supplied for a publication database definition for a single master replication system See sections 6 2 2 and 6 3 for a multi master replication system Parameters pubsvrfile The file containing the publication server login information dbid The publication database ID of the publication database definition to be updated host The IP address of the host on which the publication database server is running port The port number on which the database server is listening for connections user The publication database user name encrypted pwd The password of the database user in encrypted form See Section 8 3 4 for directions on using the encrypt command to generate an encrypted password pwdfile The file containing the password of the database user in encrypted form oraconnectiontype Copyright 2012 EnterpriseDB Corporation All rights reserved 327 Postgres Pl
445. ype eee 408 9 3 7 Restricted Mode Operation ssiiyic s ccccsancavsdeelssenccvaunccadesedseanaavecsceetnbeacentoasans 410 Copyright 2012 EnterpriseDB Corporation All rights reserved 8 Postgres Plus xDB Replication Server with Multi Master User s Guide 1 Introduction This document describes the installation configuration architecture and operation of the Postgres Plus xDB Replication Server with Multi Master Postgres Plus xDB cross database Replication Server with Multi Master referred to hereafter as xDB Replication Server is an asynchronous replication system available for PostgreSQL as part of EnterpriseDB s Postgres Plus Solution Pack and for EnterpriseDB s Postgres Plus Advanced Server database product xDB Replication Server can be used to implement replication systems based on either of two different replication models single master master to slave replication or multi master replication Regardless of the chosen replication model xDB Replication Server is extremely flexible and easy to use For single master replication PostgreSQL Postgres Plus Advanced Server Oracle and Microsoft SQL Server are supported in an assortment of configurations including cascading replication allowing organizations to utilize it in multiple use cases with a variety of benefits The following are some combinations of cross database replications that xDB Replication Server supports for single master replicati
446. ystem using the xDB Replication Console or the xDB Replication Server CLI The logical components are stored as part of the replication system metadata in one or more xDB Control databases Creating a replication system requires the following steps e Register a publication server e Create a publication database definition e Create a publication For a single master replication system you then perform the following e Register a subscription server e Create a subscription database definition e Create a subscription For a multi master replication system you create additional master nodes by creating additional publication database definitions Each of these steps creates a logical component that is represented by a node in the replication tree of the xDB Replication Console See Chapter 4 for a description of the xDB Replication Console A brief description of these components is given in the following sections 2 3 2 1 Publication Server When you install a publication server on a host the publication server program is installed started and establishes a session with the xDB Control database that you Copyright 2012 EnterpriseDB Corporation All rights reserved 33 Postgres Plus xDB Replication Server with Multi Master User s Guide designated during the installation process The connection information for the xDB Control database is stored in the xDB Replication Configuration file created and stored on the host s file sys

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