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LeftHand Networks® Remote Copy User Guide

1. 82 Sample Remote Copy Configurations Using Remote Copy for Data Migration or Cloning Configuration Diagram Application Workstations Lod Team 1 Design Team 2 Application CAD Server CAD Server for Servers for Current Next Generation Product Product Read wWirite Read Only Primary foes Remote Volume Storage Primary Snapshot Production Site 1 Production Site 2 Figure 3 12 Data migration example configuration How This Configuration Works for Data Migration Suppose you want to create a complete copy of a volume for an application to use in a different location 1 Configure a cluster of storage nodes in the new location to contain the copied volume 2 Create a one time remote snapshot of the volume onto the cluster in the new location If your application server uses multiple volumes that must be in sync use a script to quiesce the application before creating remote snapshots Optional You can create regular one time snapshots and use remote copy to move the snapshots to the remote cluster at your convenience 3 On the cluster in the new location make the remote volume into a primary volume Sample Remote Copy Configurations 83 Using Remote Copy for Data Migration or Cloning 4 Configure the application server in the new location to access the new primary volume Figure 3 13 shows migration of data by making a remote volume into a primary volume Application Workst
2. Sample Remote Copy Configurations 79 Using Remote Copy for Off site Backup and Recovery Application Workstations Clustered Application Restore Application Serer Serer Servers Read wWrite Primary Volume storage 3 00 PM Subnet Snapshot 3 00 PAS Primary Remote Snapshot Snapshot 7 00 PMS 1 00 PMS Primary Remote Snapshot Snapshot 17 00 AM 17 00 AM Figure 3 10 Non destructive rollback from the primary snapshot e To roll back the remote snapshot you must first make the remote volume into a primary volume This will stop scheduled creation of remote snapshots which may jeopar dize your high availability disaster recovery or routine backup strategies Figure 3 11 shows rollback of the remote snapshot 80 Sample Remote Copy Configurations Using Remote Copy for Off site Backup and Recovery Application Workstations Clustered Application Application Server Servers Read wWrite Read Only Read wWrite Primary Primary Volume i i Volume Volume Storage 5 00 PM F 5 00 PM i Subnet Primary Remote Snapshot Snapshot 3 00 PAS 3 00 PAS Primary Remote Snapshot Snapshot Snapshot 7 00 PAS 1 00 PM 1 00 PA Primary Remote n Primary Snapshot Snapshot f Snapshot 11 00 AM 47 00 AM 77 00 AM Figure 3 11 Non destructive rollback from the remote snapshot Best Practices Roll back the primary snapshot and keep the remote snapshots as a backup To ensure that Remote Copy continues
3. LeftHand Networks Remote Copy User Guide LeftHand Networks Inc 2580 55th Street Boulder CO 80301 303 449 4100 www LeftHandNetworks com Copyright 2001 2008 LeftHand Networks Inc This manual is the confidential and proprietary product of LeftHand Networks Inc Any unauthorized use reproduction or transfer of this manual without the express written consent of LeftHand Networks Inc is strictly prohibited This manual is designed to provide accurate and authoritative information in regard to the use of the SAN iQ Centralized Management Console and the SAN iQ software proprietary products of LeftHand Networks Inc Information in this document is subject to change without notice and does not represent a commitment on the part of LeftHand Networks Inc The software described in this manual is furnished under a license agreement The software may be used or copied only in accordance with the terms of the agreement It is against the law to copy the software on any medium except as specifically allowed in the license agreement The software distributed to you by LeftHand Networks Inc includes certain software packages indicated to be subject to one of the following open source software licenses GNU General Public License GPL the GNU Lesser General Public License LGPL or the BSD License each an OSS Package Refer to the license_readme file included with the software for additional inform
4. Reconfigure scripts for failover on the application servers Using Remote Copy 57 Rolling Back Primary and Remote Volumes Rolling Back Primary and Remote Volumes Rolling back a volume from a snapshot is one method for reverting to an earlier copy of the data on a volume Rolling back procedures require that you delete any snapshots that were created after the snapshot that is rolled back to New for Release 8 0 Consider using the SmartClone feature to clone a volume from a snapshot that contains the earlier copy of the data you want to use Creating a SmartClone volume preserves all snapshots while providing an exact copy of the desired data The SmartClone volume consumes no extra space on the SAN See detailed infor mation in Chapter 14 SmartClone volumes in the LeftHand SAN User Manual Rolling Back a Primary Volume Rolling back a primary volume to a snapshot replaces the original volume with a volume that contains the snapshot s data The new volume has the same name than the original Prerequisites e Stop applications from accessing the volume Warning Any remote snapshot that has not completed copying is canceled 1 Log in to the management group that contains the primary volume that you want to roll back Select the snapshot that you want to roll back to 3 Review the snapshot Details tab to ensure you have selected the correct snapshot 58 Using Remote Copy Rolling Back Primary and
5. Migration and Data Mining 60 Disassociating Remote Management COUPS iane eie ete ara EE aa a a 60 Sample Remote Copy Configurations VEE VIG Wiest aaah case a E e SAN 63 Using Remote Copy for Business COMUNUANCE 4 siec siniitive sazeietigtieustseaenees 63 Using Remote Copy for Off site Backup ANG Recovery s c xcsassnccdesteccgatdvcsateestecebannens 74 Index 85 Using Remote Copy for Data Migration of COMING ory az ccszgccrecssbensttnankagedetaeoentoetas vi Understanding and Planning Remote Copy Remote Copy Overview Remote Copy provides a powerful and flexible method for repro ducing data and keeping that replicated data available for disaster recovery business continuance backup and recovery data migra tion and data mining Topics Covered in this Chapter e How Remote Copy Works e Planning for Remote Copy e Using Schedules for Remote Copy How Remote Copy Works Remote Copy uses the existing volume and snapshot features along with replication across geographic distances to create remote snapshots The geographic distance can be local in the same data center or on the same campus metro in the same city or long distance cross country global For example the accounting department in the corporate head quarters in Chicago runs the corporate accounting application and stores the resulting data The designated backup site is in Detroit Nightly at 11 00 p m
6. merging for failback 67 synchronizing after failover 54 transfer rate bandwidth setting 25 Data Migration and volume cloning 82 configuration diagram 83 configuration for 82 using Remote Copy for 82 85 with remote snapshots 60 Data Mining split mirror 60 with remote snapshots 60 Deleting remote snapshot schedule 4 remote snapshots 30 snapshot schedules 39 40 Disassociating Management Groups 60 62 for PrimeSync 24 Disaster Recovery affordable using Remote Copy 69 74 E Editing remote snapshot schedules 40 4 remote snapshots 29 F Failback merging data for 67 to production configuration 66 Failover configuring 42 data availability during 65 planning 42 resuming production after 53 57 scripting for 42 setting up new site 57 synchronizing data after 54 timeline for 54 to backup application server 66 with Remote Copy 69 G Glossary for Remote Copy 2 Graphical Representations of Remote Copy 4 H High Availability and failover 69 and Remote Copy 68 best practices 67 configuration diagram 64 configuration for 64 configuration of Remote Copy 69 I Icons for Remote Copy 4 M Management Groups disassociating 60 62 disassociating PrimeSync 24 temporary for PrimeSync 23 Merging data for failback 67 Monitoring progress of remote copy 35 remote copy details 32 35 remote snapshots 30 35 N Non Destructive Rollback best practices 8 configuration diagram 78 configuration for 7
7. the time required to copy a snapshot is to run a test of the actual process In the test you take 2 remote snapshots of the primary volume Because the first remote snapshot copies the entire volume it takes longer to copy The second remote snapshot copies only changes made to the volume since the first remote snapshot Because you create the second remote snapshot after the time interval you intend to schedule the copy time for the second remote snapshot is more representative of the actual time required for copying subsequent remote snapshots 1 Create a remote snapshot of the primary volume 2 Wait for the copy to finish 3 Create another remote snapshot of the primary volume 4 Track the time required to complete the second remote snapshot This is the minimum amount of time that you should allow between scheduled copies Be sure to check the remote bandwidth setting for the other for the management group with the Edit Management Group command This setting affects the time required to copy a remote snapshot 10 Understanding and Planning Remote Copy Using Schedules for Remote Copy Capacity Does the cluster that contains the remote volume have sufficient space to accommodate scheduled snapshots See the chapter Provisioning Storage in the LeftHand SAN User Manual for information about managing capacity If the cluster does not have sufficient space available the remote snapshot appears in the CMC and it f
8. 1 At the production location you create a snapshot of the primary volume this is called the primary snapshot 2 You create a remote volume at the remote location Then you create a remote copy of the primary snapshot to the remote volume 3 The system copies data from the primary snapshot to the remote snapshot 1 System takes a snapshot 2 System creates an empty snapshot of the primary volume of the remote volume Primary Volume cov Remote Volume Read Write Pointer to remote Accessed by f snapshots application server Be eat Source for primary snapshots Primary Snapshot Remote Snapshot Primary Location Remote Location 3 System copies data from the primary snapshot to the remote snapshot Figure 1 1 Basic flow of Remote Copy Understanding and Planning Remote Copy 3 How Remote Copy Works ae Note Both primary and completed remote snapshots are the same as regular snapshots See the chapter Working with Snapshots in the LeftHand SAN User Manual oe Note Remote Copy can be used on the same site even in the same management group and cluster Graphical Representations of Remote Copy The Centralized Management Console displays special graphical representations of Remote Copy Copying the Primary Snapshot to the Remote Snapshot When the primary snapshot is copying to the remote snapshot the CMC depicts the process with a moving graphic of pages from the prim
9. Snapshot window opens shown in Figure 2 11 Edit Snapshot Volume Hame RemLogs Snapshot Hame Description Servers Assign and Unassign Servers Cancel Figure 2 11 Editing a remote snapshot 4 Change the desired information and click OK Deleting a Remote Snapshot 1 Log in to the management group that contains the remote snapshot Select the remote snapshot in the navigation window 3 Click Snapshot Tasks and select Delete Snapshot from the menu A confirmation message opens 4 Click OK and then click Delete Snapshot in the next confir mation window Monitoring Remote Snapshots Information for monitoring remote snapshots is available from multiple sources Active monitoring provides you with the capa bility to configure alerts that you view in the alert window as well as receiving alerts as emails and through SNMP traps The Alert 30 Using Remote Copy Monitoring Remote Snapshots window also provides real time monitoring information for remote snapshots when you are logged in to the CMC Monitoring Remote Snapshots Details from the Tab Window View information about each remote snapshot in both the Remote Snapshots tab and in the Remote Snapshot Details window Viewing Information in the Remote Snapshot Tab The Remote Snapshots tab displays a list of remote snapshots connected with a selected item in the navigation window For example if
10. accounting updates are copied to the Detroit backup facility using Remote Copy Understanding and Planning Remote Copy 1 How Remote Copy Works Glossary for Remote Copy The following terminology is used in describing the components and processes involved in Remote Copy Table 1 1 Remote Copy Glossary Term Definition Primary Volume Primary Snapshot The volume which is being accessed read write by the applica tion server The primary volume is the volume that is backed up with Remote Copy A snapshot of the primary volume which is created in the process of creating a remote snapshot The primary snapshot is located on the same cluster as the primary volume Remote Volume The volume that resides in the Remote Copy location where the remote snapshots are created The remote volume contains no data It acts as a pointer to tell the system where to make the copy of the primary snapshot The remote volume can be stored in these ways e in the same cluster in the same management group e ina different cluster in a different management group e ina different cluster in the same management group Remote Snapshot An identical copy of a primary snapshot The remote snapshot is located on the same cluster as the remote volume Remote Copy Pair The primary volume and its associated remote volume Failover The process by which the user transfers operation of the appli cation server ove
11. again and the remote management group you disassociated from is gone from the list 7 Click OK to return to the navigation window 62 Using Remote Copy Sample Remote Copy Configurations Overview Because of its flexibility Remote Copy is useful in a variety of configurations The sample configurations described in this chapter show only a few ways to use Remote Copy for business continuance backup and recovery data migration and data mining Using Remote Copy for Business Continuance Business continuance comprises both disaster recovery and high availability of data If using Remote Copy for business continu ance data are stored off site and are readily available in the event of a site or system failure Achieving High Availability Creating remote snapshots in remote locations with Remote Copy can ensure that applications such as SQL Server Oracle and Exchange have access to backup copies of data volumes if pro duction application servers or data volumes fail Using off site remote snapshots of your production volumes you can configure a backup application server to access those remote snapshots or volumes Off site remote snapshots particularly when supplemented with synchronous volume replication within a cluster ensures high availability of critical data volumes Sample Remote Copy Configurations 63 Using Remote Copy for Business Continuance Configuration for High Availability To use re
12. for an illustration of this configuration Configuration Diagram Application Workstations OT Ethernet Corporate LAN Clustered Application Restore Application Serwer Serer Servers Read Write Read Only Primary Volume Sa 5 00 PAS Subnet Snapshot Snapshot 3 00 PM 3 00 PAS Remote Snapshot 1 00 PM Remote Snapshot Snapshot 44 00 AM 44 00 AM Figure 3 9 Non destructive rollback example 78 Sample Remote Copy Configurations Using Remote Copy for Off site Backup and Recovery How This Configuration Works for Non Destructive Rollback You can choose to roll back either the primary snapshot or the remote snapshot Rolling back one of the snapshots requires that you delete more recent snapshots of that volume The other volume retains the full set of snapshots You can continue to make snapshots even though one side was rolled back and the other side was not When deciding whether to roll back the primary or remote volume consider the following e When you roll back the primary snapshot to a primary volume any applications accessing the primary volume will no longer have access to the most current data as the primary volume has been rolled back to a previous state If the primary volume must be synchronized with other volumes accessed by the same application consider rolling back the remote volume instead Figure 3 10 shows rollback of the primary snapshot while leaving the remote snapshots intact
13. primary Site A volume to the temporary PrimeSync management group over Gigabit Ethernet See Creating a Remote Snapshot on page 15 3 Ship the storage nodes to the remote Site B Power them on and discover them in the CMC to display the temporary PrimeSync management group cluster and volume 4 Copy the remote snapshot from the temporary PrimeSync management group to the existing remote Site B management group Using Remote Copy 23 Working with Remote Snapshots Disassociate the temporary PrimeSync management group from the remote Site B management group For detailed instructions see Disassociating Remote Management Groups on page 60 Delete the temporary PrimeSync management group Now set up the desired Remote Copy relationship such as configuring a schedule to remote snapshot the volume from the primary Site A to remote Site B management group Note Be sure you use the first initial snapshot used for the temporary PrimeSync management group copy to create the second remote copy or the schedule to remote snapshot the volume You are now setting up the remote copy that goes from primary site A directly to remote site B and keeps that relationship going forward Note PrimeSync ensures that the proper relationship is established between the original primary volume and the remote site Subsequent remote snapshots from the primary site to the remote site are incremental For more information on PrimeS
14. to operate roll back the primary volume as follows 1 Preserve the current state of the primary volume that you want to roll back by creating a one time manual remote snapshot of it Sample Remote Copy Configurations 81 Using Remote Copy for Data Migration or Cloning 2 Roll back the volume Before roll back scheduled remote snapshots fail After the primary volume is rolled back scheduled creation of remote copies will resume correctly Completed remote snapshots remain intact Using Remote Copy for Data Migration or Cloning Remote Copy allows migration of data from one application server to another without interrupting the production application server This capability supports a number of uses such as data mining or content distribution Achieving Data Migration You can use Remote Copy to make a complete copy clone of one or more volumes without interrupting access to the original volumes This type of data migration allows you to copy an entire data set for use by a new application or workgroup To copy data from one location to another simply create a one time remote snapshot of the volume To make the remote snapshot a read write volume make it into a primary volume Configuration for Data Migration To make a copy of a volume in a remote location configure a cluster of storage nodes in the remote location with enough space to accommodate the volume See the example illustrated in Figure 3 12
15. you select a management group the Remote Snapshots tab displays the list of remote snapshots associated with that management group You can view lists of remote snapshots by management group cluster volume and snapshot levels 1 Select the appropriate item in the navigation window 2 Click the Remote Snapshot tab to bring it to the front shown in Figure 2 12 Details Use Summary Volume Use Node Use iSCSI Sessions Remote Snapshots iSCSI Primary Ma Primary Sn Remote Ma Remote Sn Complete Elapsed Time Data Copied Rate State Exchange HdatrsLog RemExcha RemLogs_ MEMES 1m 22s 247 MB 24 675 Kbi Complete Exchange HdatrsLog RemExcha RemLogs_ MEE 13m 17s 672 25MB 27 954 Kb Copying Figure 2 12 Viewing remote snapshot details in the Remote Snapshots tab Using Remote Copy 31 Monitoring Remote Snapshots You may want to check the remote snapshot details for this infor mation e Complete the incremental progress of the remote copy operation e Elapsed Time incremental time of the copy operation e Data Copied incremental quantity of data copied e Rate rate at which data is being copied or when the remote snapshot is complete the average rate for the total operation e State status of the operation Viewing Status in the Remote Snapshot Details Window The Remote Snapshot Details window displays additional details about
16. 4 Click Edit Remote Bandwidth The Edit Remote Bandwidth window opens as shown in Figure 2 10 28 Using Remote Copy Working with Remote Snapshots Edit Remote Bandwidth Eg Remote Bandwidth Note that this setting is applied at the Management Group level Defaults T1 1 544 Mb sec Custom Bonded T1 2 3 088 Mb sec Bonded T1 4 6 176 Mb sec Ethernet 10 Mb sec TS 44 736 Mb sec V Make the bandwilr act Ethernet 100BaseT 100 Mb sec lOC 3 155 Mb sec OC 12 622 Mbisec A Q Figure 2 10 Editing the remote bandwidth 5 Change the bandwidth setting as desired Canceling a Remote Snapshot When you cancel a remote snapshot as it is in progress the remote snapshot is deleted but the primary snapshot remains 1 Inthe navigation window select the remote snapshot 2 Click the Remote Snapshot tab 3 Select the remote snapshot you want to cancel from the list if it is not already selected 4 Click Remote Snapshot Tasks and select Cancel Remote Snapshot A confirmation message opens 5 Click OK Editing a Remote Snapshot You can change the description and change the server assignment of a remote snapshot Using Remote Copy 29 Monitoring Remote Snapshots 1 Log in to the management group that contains the remote snapshot Select the remote snapshot in the navigation window 3 Click Snapshots Tasks and select Edit Snapshot The Edit
17. 8 O Off Site Backup and Recovery best practices 76 configuration diagram 76 configuration for 75 using Remote Copy for 74 86 P Pausing Scheduled Snapshots 39 Planning failover 42 remote copy schedules 73 remote snapshot schedules 70 14 remote snapshots 9 Prerequisites for rolling back primary volumes 58 Primary Snapshots 17 Primary Volumes prerequisites for rolling back 58 rolling back 58 59 PrimeSync temporary management group and 23 using for first copy 23 PrimeSync See PrimeSync Production resuming after failover 53 57 R Recurring snapshots 37 41 Remote Bandwidth setting 25 Remote Copy and volume replication 6 business continuance 74 creating 4 creating the first copy 22 disassociating management groups 60 62 disassociating PrimeSync management groups 24 glossary 2 high availability 68 high availability and failover 69 high availability configuration 69 icons for 4 monitoring details window 32 35 monitoring progress of 35 overview planning checklist for remote copy schedules 73 PrimeSync 23 routine backup and recovery 74 82 Remote Snapshots canceling 29 29 creating 15 21 38 creating schedule 36 39 data migration 60 data mining 60 deleting 30 deleting scheduled 47 editing 29 editing schedules 40 41 monitoring 30 35 monitoring details window 32 35 new 16 planning 9 planning for scheduled 70 14 primary 17 retention policy 72 Remote Volumes adding 79 creating manually 20 creating on
18. Failback Using Remote Copy Volume Failover Failback Wizard Volume Failover Failback GC ie Copy Snapshot to Remote Snapshot 8 oT Ad Primary Snapshot Setup Management Group Exchange Volume Hame BkupLogs Snapshot Hame BkupLogs_SS_1 Remote Snapshot Setup Management Group RemExchange v J Include primary volumes Volume Hame RS_BkupLogs v New Remote Volume Snapshot Hame RS_BkupLogs_RS_1 Snapshot Description To continue click Next Figure 2 21 Assigning the destination for copying to the remote 9 The final step is to make the remote volume into an acting primary volume as shown in Figure 2 22 This acting primary volume connects to application servers in order to maintain business continuance or accomplish disaster recovery Using Remote Copy 47 Failover and Failback Using Remote Copy Volume Failover F ailback Wizard Volume Failover Failback ee A Make Remote Volume an Acting Primary Volume AD ad The final step is to make the remote volume LogsBackup an acting primary volume Volume Hame Description None Max Size 2 22961902 TB if fully provisoned Size 20 GB X Type Provisioning Full O Thin To continue click Next lt 4 Back Cancel Help Figure 2 22 Making the remote volume into an acting primary volume Note Note You cannot make a remote volu
19. I sessions listed Using Remote Copy 51 Failover and Failback Using Remote Copy 5 The final step is to make the remote volume into an acting primary volume as shown in Figure 2 27 This acting primary volume connects to application servers in order to maintain business continuance or accomplish disaster recovery Volume Failover Failback Wizard X Volume Failover Failback oe OOE Make Remote Volume an Acting Primary Volume bS as The final step is to make the remote volume RemLogs an acting primary volume Volume Name Description Max Size 5476 37744 GB if fully provisioned Size 5 0 cs x Type Provisioning Full O Thin To continue click Next lt 4 Back Cancel Help Figure 2 27 Making the remote volume into an acting primary volume 6 Click Finish The final window of the wizard displays a summary of the actions and a reminder to reconnect your iSCSI sessions as shown in Figure 2 28 52 Using Remote Copy Resuming Production After Failover Volume Failover F ailback Wizard Eg Volume Failover Failback oe X Summary and Reminder to Reconnect Applications At gt Volume Failover Summary The following steps were performed to fail over to the remote volume 1 Ensured connected iSCSI sessions were logged off before failover 2 Made remote volume RemLogs an acting primary volume Be sure to reconnect all s
20. Remote Volumes 4 Click Snapshot Tasks on Details tab and select Roll Back Volume The Roll Back Volume window opens shown in Figure 2 29 and Figure 2 30 Centralized Management Console X WARNING There is at least one connected iSCSI session associated with volume HdatrsLogs To avoid possible data inconsistencies you must stop any applications and log off these sessions from the initiators before proceeding All changes to volume HdatrsLogs since snapshot HdatrsLogs_5S_2 was created will be lost To continue with the operation click OK To create a new SmartClone volume instead click New SmartClone Volume To exit the operation without making changes click Cancel oK New Smartctone voume Cancel Figure 2 29 Rolling back a primary volume if iSCSI sessions are still connected Centralized Management Console x WARNING All changes to volume BkupLogs since snapshot BkupLogs_FoFb_SS_1 was created will be lost To continue with the operation click OK To create a new SmartClone volume instead click New SmartClone Volume To exit the operation without making changes click Cancel l K New Smartcione votume l Cancel Figure 2 30 Rolling back a primary volume if iSCSI sessions are not connected 5 Log off any connected iSCSI sessions 6 Click OK The primary snapshot version of the primary volume is restored as a volume with the sam
21. ___ Initiator N Chap Name Gateway Connection inititor IPP Identifier E gt ExchLo ign 1991 10 0 60 32 10 0 11 16 40000137 To continue click Next Figure 2 19 Reminder to disconnect the iSCSI sessions listed Using Remote Copy 45 Failover and Failback Using Remote Copy 5 Disconnect the iSCSI sessions if any are displayed and click Next The next window begins the process to make the primary volume into a remote volume 6 Next you can type a name and a description for the snapshot that will be taken of the current primary volume shown in Figure 2 20 This snapshot preserves the existing data on the volume Volume Failover Failback Wizard Volume Failover Failback oe DOGE Make Primary Volume a Remote Volume e set The next step is to make the primary volume a remote volume Volume BkupLogs in management group Exchange is currently a primary volume When it is changed to a remote volume a snapshot will be created with the name below to save any data currently on the volume Snapshot Hame BkupLogs_SS_1 Snapshot Description To continue click Next Figure 2 20 Creating a snapshot before making a primary volume into a remote volume 7 Click Next 8 The next window is where you designate the destination for copying the snapshot to a remote snapshot shown in Figure 2 21 46 Using Remote Copy Failover and
22. a remote snapshot 1 Inthe tab window select the Remote Snapshots tab to bring it to the front Select a remote snapshot from the list 3 Click Remote Snapshot Tasks and select View Remote Snapshot Details The Remote Snapshot Details window opens as shown in Figure 2 13 32 Using Remote Copy Monitoring Remote Snapshots Source Info Time Primary Mgmt Group Exchange Start Time 09 29 2008 02 45 52 PM MDT Primary Snapshot HdqtrsLogs_SS_1 Elapsed Time 1m 22s Remote Mgmt Group RemExchange Est Time Remaining Os Remote Snapshot RemLogs_RS_1 Completion Time 09 29 2008 02 47 15 PM MDT Original Mgmt Group Exchange Original Snapshot HadqtrsLogs_SS_1 Status Data Manual Scheduled Manual Data Copied 247 MB Snapshot Scanned 100 Data Remaining 0 MB State Complete Current Rate NIA Avg Rate 24 675 Kbisec Figure 2 13 Viewing remote snapshot details During the remote copy process the Remote Snapshot Details window reports current data for the statistics When the copy is completed the statistics show summary data Figure 2 13 shows a completed remote copy Table 2 1 lists the values for the statistics reported in the Remote Snapshot Details window Table 2 1 Values for Remote Snapshot Details window Statistic Values Source Info Section Primary Mgmt Group The management group containing the primary volume and snapshot Primary Snapshot The primary snapshot Rem
23. andwidth X Calculate a Custom Bandwidth Speed Select the bandwidth speed and the percentage to calculate a fractional bandwidth T1 1 544 Mb sec vr BES 189 Kb sec Note This speed will be converted to Kbh sec and displayed in the Custom field upon returning to the Edit Remote Bandwidth window Figure 2 8 Calculating a custom value for setting remote bandwidth 26 Using Remote Copy Working with Remote Snapshots Best Practice Set the bandwidth speed the same in both directions unless you have an asymmetrical WAN link To Set the Bandwidth 1 Inthe navigation window select the management group either the remote or the primary one 2 Click Management Group Tasks and select Edit Management Group The Edit Management Group window opens as shown in Figure 2 9 3 Select the remote management group remote or primary Using Remote Copy 27 Working with Remote Snapshots Edit Management Group Group Hame Exchange Group Mode Normal Mode Local Bandwidth Priority Bandwidth Priority 4 MB sec How Dol Set My Bandwidth Priority OES CSS SCV ee Pe eae ey I 0 25 4 10 20 30 40 Max Application Data Access Rebuild Remote Management Groups Management Group Bandwidth to Remote Bandwidth to Primary Connected RemExchange Custom 32768 Kb sec Custom 32768 Kb sec Yes Disassociate Edit Remote Bandwidth Cancel Figure 2 9 Editing a remote management group
24. ary to the remote snapshot as illustrated in Figure 1 2 The pages move in the direction of the data flow from primary to remote snapshot 4 Understanding and Planning Remote Copy How Remote Copy Works lt LeftHand Networks Centralized Me Getting Started st Configuration Summary or Exchange Y Servers 1 won Administration B Sites E ExchLogs lt lt Performance Monitor Storage Nodes 3 f Denver 1 Denver 2 S gt Denver 3 amp Volumes 2 and Snapshots 2 Bkuplogs 1 Le BkupLogs_SCsnap A B HadiqtrsLogs r ton RemExchange FY Servers 0 2 Administration B Sites RemExchLogs Performance Monitor Storage Nodes 1 l Volumes 1 and Snapshots 2 RemLogs 2 RemLogs_SS_1 Figure 1 2 Icons depicting the primary snapshot copying to the remote snapshot Graphical Legend for Remote Copy Icons The graphical legend available from the Help menu depicts the icons associated with Remote Copy Figure 1 3 displays the Remote Copy states icons from the graphical legend Understanding and Planning Remote Copy 5 How Remote Copy Works e tems Hardware Memore rom SNAPSHOT Primary Shared Snapshot Remote Shared Snapshot Cluster Management Group Item needs attention Virtual Manager Failover Manager Remote Snapshot Pair ad ill a Shared Snapshot Relationship Figure 1 3 Icons for Remote Copy in t
25. as configured to access the remote now primary volume operation of the backup application server begins The application continues to operate after the failover to the backup application server Failback to the Production Configuration When the production server and volumes become available again you have two failback options Resume operations using the original production server and return the backup volumes to their original remote status as illustrated in Figure 3 3 This will require migration back onto the production volumes of data that were written to the backup volumes since the failure Continue operating on the backup application server When the production server and volumes become available configure the production server to be the backup server role reversal 66 Sample Remote Copy Configurations Using Remote Copy for Business Continuance Merging Data for Failback In the failover scenarios described above there are probably two snapshots with different data As part of failback users must make a decision whether to merge the data from the two snapshots and the most effective method for doing so See Syn chronizing the Data Between the Acting Primary Volume and the Original Primary Volume on page 55 Application Workstations Acting Clustered Production gg Backup Production Application Application m pplication Application f Servers Server Server Read Only Read Write Pr
26. ating the remote snapshot You can create remote volumes and snapshots within the same management group In that case you only log in to the one management group Log in to the remote management group In the navigation window select the primary volume or snapshot If you want to copy an existing snapshot to a remote management group select that snapshot at this step Click Snapshot Tasks and select New Remote Snapshot The New Remote Snapshot window opens as shown in Figure 2 1 16 Using Remote Copy Working with Remote Snapshots New Remote Snapshot Primary Snapshot Setup Management Group Volume Hame Snapshot Hame Remote Snapshot Setup Management Group Volume Hame Snapshot Hame Snapshot Description mE Exchange HdqtrsLogs Create Primary Snapshot gt New Snapshot Exchange C Include primary volumes New Remote Volume Figure 2 1 Creating a new remote snapshot Creating the Primary Snapshot 1 In the Primary Snapshot Setup box click New Snapshot The New Snapshot window opens shown in Figure 2 2 Figure New Snapshot Ix Volume Hame HdatrsLogs Snapshot Hame Description Servers Assign and Unassign Servers Cancel 2 2 Creating a new primary snapshot Enter a name for the snapshot Using Remote Copy 17 Working with Remote Snapshots Ba __ Tip Ma
27. ation regarding the application of these licenses to the OSS Packages and your rights and responsibilities under these licenses In addition the software described in this manual includes open source software developed by the Apache Software Foundation The Legion of the Bouncy Castle Free Software Foundation Inc and OpenPegasus Other included software is under license agreements with Hewlett Packard Development Company L P IBM Corp EMC Corporation Symantec Corporation and The Open Group LeftHand Networks the LeftHand Networks logo SAN iQ and AEBS are registered trademarks of LeftHand Networks Inc LeftHand ThinClone and SmartClone are trademarks of LeftHand Networks Inc Part 26200001813 Rev A iii Table Of Contents Understanding and Planning Remote Copy Remote Copy Overview ccccceseceeceeeeeeeeeeeees 1 Topics Covered in this Chapter 0 0 eee 1 How Remote Copy Works 1 Planning for Remote Copy ceeeeeeeeeseeeneees 8 Using Schedules for Remote Copy 0 9 Using Remote Copy Remote Copy Overview ssseesesereerreeeeersee 15 Working with Remote Snapshots 0 15 Monitoring Remote Snapshots eee 30 Scheduling Remote Snapshots eee 36 Failover and Failback Using Remote Copy 42 Resuming Production After Failover 53 Rolling Back Primary and Remote Volumes n ea A aise 58 Using Remote Snapshots for Data
28. ations Design Design Team 2 Application Team 2 CAD Server for Servers CAD Servet Next Generation 4 for Current Product P Product Read Wirite Primary f i as Primary Volume 4 ee ie Volume 2 Storage Subnet Primary Primary Snapshot Snapshot i gt Snapshot 2 Production Site 1 Production Site 2 Figure 3 13 Configuration after data migration 84 Sample Remote Copy Configurations Index A Adding a remote snapshot schedule 36 39 aremote volume 9 remote snapshots 5 2 Affordable Disaster Recovery best practices 73 configuration 70 B Backup and Recovery using Remote Copy 74 82 Benefits of Remote Copy 7 Best Practices for affordable disaster recovery 73 for high availability 67 for non destructive rollback 87 for off site backup and recovery 76 scheduled remote snapshot 6 36 scheduled remote snapshots schedule 13 Business Continuance Using Remote Copy 74 C Canceling Remote Snapshots 29 Changing backup site into new production site 57 primary volume into remote volume 43 Clone of Volume 7 Configuration for affordable disaster recovery 70 for data migration 82 for high availability 64 for non destructive rollback 78 for off site backup and recovery 75 Configuring failover 42 Remote Copy 8 Copying using Remote Copy 5 Creating first remote copy 22 first remote copy using PrimeSync 23 remote snapshots 38 split mirrors 60 D Data availability during failover 65
29. ck wizard 3 Click Next You next select the reason you are failing over the volume shown in Figure 2 18 e Use the first choice if your primary volume is available and you are planning a preemptive move of the primary volume For the steps to use the second choice see Using Failover to Remote Volume on page 49 44 Using Remote Copy Failover and Failback Using Remote Copy Volume Failover F ailback Wizard x Select the Reason for Volume Failover Failback KE ets Choose the scenario that most accurately describes your need Pg e e Select the reason that most accurately describes why you are running this wizard To move the primary volume BkupLogs To fail over the primary volume BkupLogs to the selected remote volume below To continue click Next Figure 2 18 Selecting to move the primary volume 4 Select the first choice to move the volume and click Next The next window reminds you to disconnect any iSCSI sessions connected to the volume as shown in Figure 2 19 Volume Failover Failback Wizard pag Volume Failover Failback OOGG Ensure iSCSI sessions are logged off KSE Py e t Connected iSCSI Sessions 1 How do llog off from my iSCSI sessions WARNING To avoid possible data inconsistencies you must stop any applications and log off connected iSCSI sessions Clicking Next below without first taking these actions is an advanced operation Server
30. clude primary volumes Volume Name r New Remote Volume Retain Snapshots For 1 Weeks v Retain Maximum Of Figure 2 15 Creating a new schedule for recurring remote snapshots Using Remote Copy 37 Scheduling Remote Snapshots Click Edit and select a Start At time 5 Select a recurrence interval You can schedule a snapshot every 30 minutes or more 6 Select a retention interval for the primary snapshot either number of days or number of snapshots You can retain up to 50 snapshots for a volume and up to 200 for all volumes 7 Select the management group and volume that will hold the remote snapshots Log in if you need to Click New Volume to use the wizard to create a volume if you need to make a new one 8 Set the retention interval for the remote snapshot You can retain up to 50 snapshots for a volume and up to 200 for all volumes 9 Click OK to close the scheduling window and return to the navigation and tab windows The timetable you just created is now listed in the Schedules tab view Timing for a Scheduled Remote Snapshot When you set up a schedule for recurring remote snapshots with the previous procedure you rely on the time The time zone displayed in the Schedule to Remote Snapshot a Volume windows is the time zone of the storage node through which you first logged in to the management group See Best Practices for Scheduling Remote Snapsho
31. dit Schedule Remote Snapshot window opens shown in Figure 2 16 40 Using Remote Copy Scheduling Remote Snapshots Hame Description Start At 09 29 2008 04 00 00 PM MDT Edit Recurrence Recur Every 4 Days v C Paused Hever Recur Next Occurrence 09 29 2008 04 00 00 PM MDT Primary Snapshot Setup Management Group Exchange Volume Name BkupLogs Retain Snapshots For f Weeks v O Retain Maximum Of Remote Snapshot Setup Retain Snapshots For 1 Weeks v O Retain Maximum Of Figure 2 16 Editing the schedule to remote snapshot a volume 4 Change the desired information 5 Click OK Deleting the Remote Snapshot Schedule 1 Inthe navigation window select the primary volume that has the schedule you want to delete Click the Schedule tab to bring it to the front 3 Select the schedule you want to delete Click Schedule Tasks and select Delete Schedule A confirmation message opens Using Remote Copy 41 Failover and Failback Using Remote Copy 5 Click OK Failover and Failback Using Remote Copy Configuring Remote Copy for failover provides for business con tinuance and disaster recovery When configuring failover consider both the failover and failback paths Planning Failover To achieve failover consider the following points e The location and structure of management groups and clusters e Configuration of primary and remote volumes sna
32. e Copy create copies of the original volume for use by other application servers Benefits of Remote Copy Remote Copy maintains the primary volume s availability to application servers Snapshots on the primary volume are taken instantaneously and are then copied to remote snapshots in the off site location Remote Copy operates at the block level moving large amounts of data much more quickly than file system copying Snapshots are incremental that is snapshots save only those changes in the volume since the last snapshot was created Hence failback may need to resynchronize only the latest changes rather than the entire volume Remote Copy is robust If the network link goes offline during the process copying resumes where it left off when the link is restored Understanding and Planning Remote Copy 7 Planning for Remote Copy Planning for Remote Copy Remote Copy works at the management group cluster volume snapshot and storage node level Review Table 1 3 for common configurations at various levels Table 1 3 Remote Copy SAN iQ and Storage Nodes Storage System Level Remote Copy Configuration Management Groups Create remote snapshots in the same management group or in a different management group than the primary volume If using different management groups the remote bandwidth setting of the management group containing the remote volume determines the maximum rate of data transf
33. e Copy uses the existing volume and snapshot capabilities to replicate or copy the data across geographic distances Creating a Remote Snapshot Creating a remote snapshot is the main task when working with Remote Copy You can either create a one time remote snapshot or set up a schedule for recurring remote snapshots Many of the characteristics for either case are the same Creating a remote snapshot involves these main steps e Log in to the primary and the remote management group e Create a primary snapshot of the primary volume manually When doing a schedule to remote snapshot a volume the Using Remote Copy 15 Working with Remote Snapshots Best Practice software automatically creates a primary snapshot which is then copied to the remote volume Either create a remote volume on a remote management group or select an existing remote volume Create the remote snapshot The best way to prepare for remote snapshots is to create the management group and volumes that will be remote before taking the snapshot Although the interface allows you to create manage ment groups volumes and snapshots as you go that may be a distraction at the time a crucial snapshot is needed Getting There This procedure takes you to the New Remote Snapshot window where remote copy procedures start 1 In the navigation window log in to the management group that contains the primary volume or snapshot for which you are cre
34. e Into a Remote Volume Make any primary volume into a remote volume First the system takes a snapshot of the primary volume to preserve the existing data that are on the volume Next the primary volume is converted to a remote volume 1 Inthe navigation view select the volume that you want to convert 2 Right click and select Failover Failback Volume The Volume Failover Failback wizard opens shown in Figure 2 17 Using Remote Copy 43 Failover and Failback Using Remote Copy Volume Failover Failback Wizard Volume Failover Failback Wizard This wizard helps you to move your primary volume when backing up your data failing over to a remote volume and failing back to a primary volume This wizard can be beneficial when moving a data center or preparing for business continuance and disaster recovery The wizard helps you e Log off connected iSCSI sessions e Make the original primary volume a remote volume a snapshot of the primary volume will be taken automatically Copy the snapshot to the remote volume Make the remote volume an acting primary volume Remember to log on to the iSCSI sessions and reestablish schedules Before you start this wizard you must Log off connected iSCSI sessions wow lefthandnetworks com accessing the original primary volume To exit click Cancel at any time To continue click Next Figure 2 17 Opening the Volume Failover Failba
35. e name 7 Reconfigure application servers to access the new volume Rolling Back a Remote Volume A remote volume cannot be rolled back To roll back a remote volume make the remote volume into a primary volume and perform the steps previously mentioned Using Remote Copy 59 Using Remote Snapshots for Data Migration and Data Mining Using Remote Snapshots for Data Migration and Data Mining Use remote snapshots to create split mirrors for data mining and data migration A split mirror is a one time remote snapshot created from the volume containing the data you want to use or move Split mirrors are usually created for one time use and then discarded New for Release 8 0 Consider using the SmartClone feature to create a split mirror The SmartClone volume is an exact copy of the volume or snapshot yet consumes no extra space on the SAN See detailed information in Chapter 14 SmartClone volumes in the LeftHand SAN User Manual Creating a Split Mirror To create a split mirror perform these general steps e Create a remote snapshot e Create a server for client access e Configure clients to access the remote snapshot Disassociating Remote Management Groups Management groups become associated when linked by either remote snapshots or scheduled remote snapshots Disassociating management groups destroys all the shared knowledge between those groups Best Practice for Disassociating Management Groups Do this o
36. e scheduled remote snapshots e If performing daily remote copies schedule the remote snapshots during off peak hours If setting scheduled remote snapshots for multiple volumes stagger the schedules with at least an hour between start times for best results e Use NTP to set all storage nodes in the management group to the same time zone e Reset the management group time before creating a new schedule to remote snapshot a volume For detailed informa tion see Resetting the Management Group Time in the 36 Using Remote Copy Scheduling Remote Snapshots chapter Working with Management Groups in the LeftHand SAN User Manual Creating the Schedule Create the schedule for continuing remote snapshots 1 Inthe navigation window select the primary volume 2 Click the Schedules tab to bring it to the front 3 Click Schedule Tasks and select New Schedule to Remote Snapshot a Volume The New Schedule to Remote Snapshot a Volume window opens shown in Figure 2 15 New Schedule to Remote Snapshot a Volume X Hame BkupLogs_Sch_RS_1 Description Start At Select Start At time gt Edit Recurrence Recur Evers Days v A C Paused D Hever Recur Hext Occurrence NIA Primary Snapshot Setup Management Group Exchange Volume Hame BkupLogs Retain Snapshots For 1 Weeks v Retain Maximum Of Remote Snapshot Setup Management Group Exchange J In
37. e site Because manage ment groups and clusters are logical entities name them to reflect their remote functionality In this method the primary volume is ready You create a remote volume at the remote site to receive the snapshot Then either take the snapshot and remote copy it or create the schedule to take remote snapshots See the section on Creating a Volume in the LeftHand SAN User Manual the chapter Working With Volumes Creating a remote volume on the fly If you are using the New Remote Snapshot window you can create a needed cluster and volume as you work through the window 1 In the Remote Snapshot Setup box select a Management Group to contain the remote snapshot You must be logged in to the management group you select 20 Using Remote Copy Working with Remote Snapshots 2 Click New Volume The Management Groups Clusters and Volumes wizard opens For specific help see Chapter 1 Getting Started in the LeftHand SAN User Manual for details on working through the wizards The information you specify in the wizard fills in the New Remote Snapshot window when you exit the wizard 3 Optional Type in a description of the remote snapshot and click OK The remote copy may take some time What the System Does The system creates the remote snapshot in the cluster that contains the remote volume The system then copies the primary snapshot onto the remote snapshot The p
38. eate the primary management group and the remote management group in their respective locations You then create the initial copy of the data directly over the WAN using Remote Copy 22 Using Remote Copy Working with Remote Snapshots Use the storage nodes intended for the remote site to configure the remote management group on site and copy data locally Then ship the remote storage nodes to the remote site Use this method if you initially have all the storage nodes for the Remote Copy solution at the primary site Configure both the primary and remote management groups 2 Create the first copy of the data locally over the Gigabit Ethernet 3 Ship the storage nodes for the remote site and install the remote management group just as you configured it in the primary site Allow adequate time between the arrival of the storage nodes and the first remote copy operation The subsequent snapshots from the primary volume to the remote volume are incremental Use the PrimeSync feature of Remote Copy to configure a temporary management group create the first copy locally then ship the temporary storage node and again copy locally to the remote target Use this method if you have the primary Site A and remote site Site B configured and operational 1 While at the primary Site A use available storage nodes to create a new temporary PrimeSync management group cluster and volume 2 Make a remote snapshot of the
39. ed to synchro nize The steps to create those snapshots are described in Table 2 3 Using Remote Copy 55 Resuming Production After Failover Table 2 3 Creating snapshots of data to synchronize Volumes and Snapshots on Volumes and Snapshots on primary volume into the remote volume This automatically creates a snapshot of the acting primary volume ActPrimarySS_1 Primary Remote Management Management What This Step Action Group Group Accomplishes 1 Stop applications that are accessing the volumes 2 Make a snapshot of OrigPrimaryVol_1 Creates a the original volume fea snapshot of the OrigPrimarySS_1 original primary volume that includes the data from 1 00 1 30 p m 3 Make the acting Remotevol_1 Returns the remote manage ment group to its original configura tion In addition you capture the 1 33 to 2 00 p m data 2 Synchronize the Data Synchronize the snapshots OrigPrimarySS_1 and ActPrimarySS_1 that were created in Steps 2 and 3 of Table 2 3 e Inthe simplest case to synchronize the snapshots remote copy the remote snapshot back to the original primary volume For more detail about synchronizing see Table 1 1 Remote Copy Glossary on page 2 Creating a New Primary Volume at the Original Production Site If the original primary volume is not available designate a new primary volume synchronize the data from the acting primary 56 U
40. er to the remote snapshot Clusters Create remote snapshots in the same cluster or in a cluster different from the primary volume Volumes Primary volumes contain the data to be copied to the remote snapshot Data is copied to the remote snapshot via the remote volume The remote volume is a pointer to the remote snapshot The remote volume has a size of 0 bytes Snapshots Storage Nodes Active monitoring of each storage node notifies you when After data are copied from the primary snapshot to the remote snapshot the remote snapshot behaves as a regular snapshot copies complete or fail Active monitoring also notifies you if a remote volume or snapshot is made primary or if the status of the connection between management groups containing primary and remote volumes changes 8 Understanding and Planning Remote Copy Using Schedules for Remote Copy Planning the Remote Snapshot To create a remote snapshot meet these prerequisites Log in to both the management group that contains the primary volume and the management group that contains the target cluster where the remote snapshot will be created Designate or create a remote volume in that remote manage ment group Have enough space on the target cluster for the remote snapshot Logging in to Primary and Remote Management Groups Log in to both the primary and the remote management groups before you begin or you must log in t
41. ervers to the new acting primary volume RemLogs Also reestablish any schedules as needed Figure 2 28 Final summary and reconnect sessions reminder Resuming Production After Failover After failover occurs three scenarios exist for resuming produc tion e Failback returns operations to the original primary site once it is restored e Make the backup site into the new primary site e Set up a new primary site and resume operations at that site The task flow for restoring or recovering data and resuming the original Remote Copy configuration is different for each scenario Use these procedures when you are resynchronizing data between the acting primary volume and the recovered or newly config ured production site primary volume Using Remote Copy 53 Resuming Production After Failover Synchronizing Data After Failover After a failover there will usually be 2 snapshots or volumes that have conflicting data Recovering and synchronizing such data depends on multiple factors including the application involved For more detail about synchronizing see Table 1 1 Remote Copy Glossary on page 2 Example Scenario The following example illustrates only one process for synchro nizing data Remember that such synchronization is optional Time Line of Failover Table 2 2 Time line of failover Time Event What Happens 1 00 p m Regular hourly schedu
42. found in the LeftHand SAN User Manual e Inthe production location create a management group and a cluster of 3 storage nodes e Create volumes on the cluster and set the replication level to 2 Way e Configure the production application server to access the primary volume via iSCSI e In the backup location create a second management group and a cluster of 3 storage nodes e Create a schedule for making remote snapshots of the primary volume See Scheduling Remote Snapshots on page 36 Note Volume replication levels are set independently for primary and remote volumes Note How It Works If one of the storage nodes in the primary location fails the primary volume will still be available If all of 68 Sample Remote Copy Configurations Using Remote Copy for Business Continuance the storage nodes fail or if the application server fails then failover to the backup application server occurs and the remote snapshot s becomes available Application Workstations Clustered Production gg Backup Production Application Application m Application Application Servers Server Server Serer Read Only Read Write Primary Remote Volume Volume Primary lary Volume Acting Primary Remote Primary Snapshot Snapshot Snapshot Figure 3 4 High Availability During Failover Example Configuration Achieving Affordable Disaster Recovery Even if you do not have clustered application servers or ne
43. g remote snapshots accordingly If you do not want a large number of remote snapshots to accu mulate on your remote volume you can use several timetables for scheduled remote snapshots each with different retention policies For example suppose you want to create remote snapshots every 4 hours to ensure that no more than 4 hours worth of data are lost in an emergency In addition you want to retain 1 week s worth of remote snapshots Retaining 4 hour snapshots for 1 week can result in the accumulation of over 40 remote snapshots Another approach would be to create 2 remote snapshot schedules for the volume e One schedule to create remote snapshots every 4 hours but only retain the most recent 6 remote snapshots This will ensure that you do not lose more than 4 hours worth of data in an emergency e A second schedule to create remote snapshots every 24 hours and retain 7 remote snapshots Use remote snapshots in conjunction with local synchronous volume replication To prevent data loss reinforce Remote Copy with synchronous replication of the volume within the cluster of storage nodes at the primary geographic site With synchronous replication a single storage node can be off line and your primary volume will remain intact Sample Remote Copy Configurations 73 Using Remote Copy for Off site Backup and Recovery At the backup location you can also use synchronous replication to protect your remote volume against sto
44. he Graphical Legends window Remote Copy and Volume Replication Remote Copy is asynchronous replication of data Volume repli cation is synchronous replication Volume replication is described in detail in the LeftHand SAN User Manual in the chapter Working with Volumes Using synchronous volume replication on multiple storage nodes within a cluster in combina tion with asynchronous Remote Copy on a different cluster of storage nodes creates a robust high availability configuration Uses for Remote Copy Review Table 1 2 to see common applications for the Remote Copy application 6 Understanding and Planning Remote Copy How Remote Copy Works Table 1 2 Uses for Remote Copy Use Remote Copy for How It Works recovery Business continuance disaster Using Remote Copy store remote snapshots on a machine geographically separate The remote snapshots remain available in the event of a site or system failure at the primary site content distribution Off site backup and recovery Using Remote Copy eliminate the backup window on Split mirror data migration Using Remote Copy make a complete copy of one or an application server by creating remote snapshots on a backup server either local or remote and back up from that server more volumes without interrupting access to the original volumes Move the copy of the volume to the location where it is needed Volume clone Using Remot
45. he management group that contains the remote snapshot the remote management group When setting the remote bandwidth you can choose from a list of common network types or you can calculate a custom rate based on your particular requirements Select Remote Bandwidth Rate You may either select a preset speed from a list of standard network types or calculate a custom speed based on your specific requirements Remember the speed is the maximum rate at which data will be copied Defaults Setting When setting remote bandwidth selecting Defaults allows you to choose from a list of common network types as shown in Figure 2 7 Using Remote Copy 25 Working with Remote Snapshots Edit Remote Bandwidth Eg Remote Bandwidth Note that this setting is applied at the Management Group level Defaults T1 1 544 Mb sec Custom Bonded T1 2 3 088 Mb sec Bonded T1 4 6 176 Mb sec Ethernet 10 Mb sec TS 44 736 Mb sec OC 3 155 Mb sec OC 12 622 Mb sec Figure 2 7 Defaults setting for remote bandwidth Custom Setting The custom setting for remote bandwidth defaults to 32768 Kb or about 4 Mb Use the calculation tool to identify a desired bandwidth setting For example if you have a T1 line and you want to set the remote bandwidth to 12 of that capacity you can use the calculation tool to find the correct value 189 Kb as shown in Figure 2 8 Calculate Custom B
46. he volume for which you want to pause the schedule Click the Schedules tab to bring it to the front 3 Select the schedule you want Click Schedule Tasks on the Details tab and select Pause Schedule Using Remote Copy 39 Scheduling Remote Snapshots 5 In the Confirm window click OK In the Next Occurrence column of the Schedules tab window this snapshot schedule is marked as paused Make a note to resume this snapshot schedule at a convenient time Resume a Schedule 1 In the navigation window select the volume for which you want to resume the snapshot schedule Click the Schedules tab to bring it to the front Select the schedule you want Click Schedule Tasks on the Details tab and select Resume Schedule In the Confirm window click OK In the Next Occurrence column of the tab window this snapshot schedule shows the date and time the next snapshot will be created Editing the Schedule to Remote Snapshot a Volume When editing the timetable for a schedule to remote snapshot a volume you can change the following items Schedule description start date and time recurrence policy Primary Setup tetention policy Remote Setup tretention policy To Edit the Remote Snapshot Schedule 1 In the navigation window select the primary volume that has the schedule you want to edit Click the Schedules tab and select the schedule to edit Click Schedule Tasks and select Edit Schedule The E
47. hot is deleted only after its counterpart primary snapshot You cannot retain fewer remote snapshots than primary snapshots when setting your retention policies 12 Understanding and Planning Remote Copy Using Schedules for Remote Copy Note Best Practices Note Over the course of time through deletion of primary snapshots if you accumulate more remote snapshots than primary snapshots the remote snapshots become regular snapshots when their corresponding primary snapshots are deleted You can identify them as remote snapshots by their names since the naming convention is established as part of creating the remote snapshot schedule e Retain at least 2 primary snapshots to ensure that only incre mental copying is required for remote snapshots e Review your remote copy schedule to ensure that the frequency of the remote copies correlates to the amount of time required to complete a copy Use the checklist in Table 1 5 to help plan scheduled remote snapshots Table 1 5 Scheduled Remote Copy Planning Checklist Configuration Category Characteristic Scheduled Snapshot Start Time e Start date mm dd yyyy e Start time mm hh ss for the schedule to begin Recurrence e Recurrence is a yes or no choice Do you want to take a remote snapshot one time in the future and not have it recur or do you want a remote snapshot to be taken ona regular schedule Frequency minutes hours days or wee
48. il able and you want to get an acting primary volume into pro duction 50 Using Remote Copy Failover and Failback Using Remote Copy Volume Failover F ailback Wizard X Select the Reason for Volume Failover Failback oe oot Choose the scenario that most accurately describes your need hS A ag Pi 4 Select the reason that most accurately describes why you are running this wizard To move the primary volume HdatrsLogs To fail over the primary volume HdqtrsLogs to this remote volume RemLogs To continue click Next Figure 2 25 Selecting to failover to a remote volume Select the second choice to failover to the remote volume and click Next The next window reminds you to disconnect any iSCSI sessions connected to the volume as shown in Figure 2 26 Volume Failover Failback Wizard A Volume Failover Failback yy e Ensure iSCSI sessions are logged off oe eee Connected iSCSI Sessions 1 How do log off from my iSCSI sessions WARNING To avoid possible data inconsistencies you must stop any applications and log off connected iSCSI sessions Clicking Next below without first taking these actions is an advanced operation Server initiator N Chap Name Gateway Connection Initiator IP P Identifier R ExchLo ign 1991 10 0 60 32 10 0 11 16 40000137 To continue click Next Figure 2 26 Reminder to disconnect any iSCS
49. imary Remote Acting Volume Volume Primary Storage lake Remote Volume Subnet Acting Remote Primary Snapshot Snapshot Snapshot Figure 3 3 High availability configuration during failback Best Practices Remote Snapshots with Volume Replication Use remote snapshots in conjunction with local synchronous volume replication Using remote snapshots alone any data written to the primary volume since the most recent remote snapshot was created will be unavailable if the primary volume is unavailable Sample Remote Copy Configurations 67 Using Remote Copy for Business Continuance However you can lessen the impact of primary volume failure by using synchronous volume replication Volume replication allows you to create up to 4 copies of a volume on the same cluster of storage nodes as the primary volume The only limitation is that the cluster must contain at least as many storage nodes as replicas of the volume Replicating the volume within the cluster ensures that if a storage node in the cluster goes down replicas of the volume elsewhere in the cluster will still be available For detailed information about volume replication see the chapter Provisioning Storage in the LeftHand SAN User Manual for details Example Configuration This example illustrated in Figure 3 4 uses 3 storage nodes per cluster However this scenario can use any number of storage nodes Information about creating clusters and volumes can be
50. ining MB GB or TB Amount of data remaining to be copied in smallest unit size Current Rate Kb sec Current rate of data being copied in Kb second This rate is recalculated regularly throughout the remote copy process N A if not yet available or completed Avg Rate Kb sec Average rate of copy progress 34 Using Remote Copy Monitoring Remote Snapshots You can leave the Remote Snapshot Details window open and monitor the progress of the remote copy An example of a Remote Snapshot Details window with a remote copy in progress is shown in Figure 2 14 Source Info Time Primary Mgmt Group Exchange Start Time 09 29 2008 03 20 17 PM MDT Primary Snapshot BkupLogs_SCsnap Elapsed Time 1m 51s Remote Mgmt Group RemExchange Est Time Remaining 2m 57s Remote Snapshot RemBkupLogs_RS_1 Completion Time N A Original Mgmt Group Exchange Original Snapshot BkupLogs_SCsnap Status Data Manual Scheduled Manual Data Copied 345 25 MB Snapshot Scanned Data Remaining 1 1 GB State Copying Current Rate 25 480 Kb sec Avg Rate 25 480 Kb sec Close Figure 2 14 Viewing remote snapshot details for remote copy in progress Configuring Active Monitoring Alerts for Remote Copy There are four variables for remote snapshots for which you can configure alerts Notification for these variables automatically displays as default alert messages in the alert window You can also configure Active Monito
51. ion Application Clustered Production Backup Production Servers Serer Server Serer Read Only Read Write Primary Remote Acting Volume Volume Primary Storage Make Pri Volume Subnet t Acting Primary Remote Primary Snapshot Snapshot Snapshot Figure 3 2 High availability configuration during failover Data Availability if the Primary Volume or Production Application Server Fails If either the primary volume or production application server in your production site fails only that data written to the volume since the last remote snapshot was created will be unavailable until the volume or production application server is restored Sample Remote Copy Configurations 65 Using Remote Copy for Business Continuance Failover to the Backup Application Server To maintain availability of the applications and the remaining data the following process occurs 1 A script or other application monitoring the production application server discovers that the primary volume is not available A script executes to fail over to the backup application server The backup application server executes a script to convert the remote volume into a primary volume so that the volume can be accessed by the backup application server Find informa tion about scripting in the CLIQ The SANiQ Command Line Interface User Manual and in sample scripts available on the LeftHand Networks website Because the backup application server w
52. ively small amount of space on the primary cluster e Retain up to a week s worth of remote snapshots on the backup cluster e For snapshots older than 1 week go to the backup tape Achieving Non Destructive Rollback As discussed in Rolling Back a Primary Volume on page 58 rolling a snapshot back to a volume requires you to delete any snapshots that were created since the snapshot that you roll back to For example suppose you created snapshots of a volume on Monday Tuesday and Wednesday On Thursday if you roll the volume back to Monday s snapshot then the snapshots from Tuesday and Wednesday will need to be deleted first You can use Remote Copy to roll a volume back to an old snapshot without losing the interim snapshots Because Remote Copy creates 2 sets of snapshots primary and remote snap shots you can roll a volume back to a snapshot and still retain the other set of snapshots Sample Remote Copy Configurations 77 Using Remote Copy for Off site Backup and Recovery Configuration for Non Destructive Rollback To use remote snapshots for non destructive rollback e Create a remote snapshot schedule e Inthe schedule specify the same retention policy for the primary and remote snapshots This ensures that you have copies of the same number of snapshots in your primary and remote locations Any snapshots destroyed during rollback of one volume will remain intact on the other volume See Figure 3 9
53. ke the beginning of volume and snapshot names Gy meaningful for example Snap1Exchg_03 BS 3 Optional Type in a description of the snapshot 4 Click OK to return to the New Remote Snapshot window The information for the primary snapshot is filled in as shown in Figure 2 3 That is the text for the field Snapshot Name has changed e From Create Primary Snapshot e To HdqtrsLogs_SS_1 New Remote Snapshot Primary Snapshot Setup Management Group Exchange Volume Hame HaqtrsLogs Snapshot Name HdqtrsLogs_SS_1 Figure 2 3 New primary snapshot created In the Remote Snapshot Setup box use the drop down lists and select the remote site management group and volume The Management Groups Clusters and Volumes wizard is available at this point if you need to create the remote management group 5 Inthe Snapshot Name field type in the name for this remote snapshot 6 Optional Type in a description for the remote snapshot 7 Click OK in the New Remote Snapshot window The remote copy of the primary snapshot to the remote volume begins as shown in Figure 2 4 18 Using Remote Copy Working with Remote Snapshots I lt LeftHand Networks Centralized M Getting Started st Configuration Summary fy Exchange Im Servers 1 aoe Administration B Sites ExchLogs Performance Monitor Storage Nodes 3 Denver 1 a Denver 2 amp gt Denver 3 vo
54. ks determines the interval between recurring scheduled remote snapshots Understanding and Planning Remote Copy 13 Using Schedules for Remote Copy Table 1 5 Scheduled Remote Copy Planning Checklist Continued Configuration Category Characteristic Primary Setup Retention Retain either e Maximum number of snapshots e Set period of time minutes hours days or weeks Remote Setup Management Group The management group to contain the remote snapshot Volume The remote volume for the remote snapshots Retention Retain either e Maximum number of snapshots This number equals completed snapshots only In progress snapshots take additional space on the cluster while they are being copied Also the system will not delete the last fully synchronized snapshot For space calculations figure N 2 with N maximum number of snapshots e Set period of time minutes hours days or weeks 14 Understanding and Planning Remote Copy Using Remote Copy Remote Copy Overview This chapter provides instructions for registering configuring and using Remote Copy for business continuance backup and recovery and failover For information about how Remote Copy works and how to plan capacity for Remote Copy see Chapter 1 Understanding and Planning Remote Copy Working with Remote Snapshots Remote snapshots are a core component of Remote Copy Remot
55. lashes red On the Details tab of the remote snapshot the status says Read only not enough space in cluster to start copy Retention Policies How long do you want to retain the primary snapshots The remote snapshots You can set different retention policies for the primary and remote snapshots For example you can choose to retain 2 primary snapshots and 5 remote snapshots The number of snapshots retained refers to completed snapshots Take the following characteristics scheduled remote snapshots into account when planning retention policies e The SAN iQ software never deletes the last fully synchro nized remote snapshot Under some circumstances such as unpredictable network speeds or varying snapshot size a scheduled remote snapshot may create primary snapshots more frequently than the remote copy process can keep up with The retention policies for scheduled remote snapshots ensure that such factors do not cause primary and remote snapshots to become unsynchronized Regardless of the retention policy defined for scheduled remote snapshots up to two additional snapshots may be retained by the system at any given time These two additional snapshots include the snapshot that is in the process of being copied and the last fully synchronized snapshot A fully synchronized snapshot is one that has Understanding and Planning Remote Copy 11 Using Schedules for Remote Copy completed copying so that the remote snapsh
56. led remote snapshot RemoteSS_1 created in remote Management Group 1 10 p m Remote copy finishes Copying is complete 1 30 p m Primary volume goes offline OrigPrimaryVol_1 offline 1 33 p m Scripted failover causes remote volume to ActPrimaryVol_1 becomes become the acting primary volume primary and active that is usable to application server 2 00 p m Original primary volume comes back online OrigPrimaryVol_1 online Data that now needs to be synchronized e Original volume which contains data from 1 00 to 1 30 p m e Acting primary volume which contains data from 1 33 to 2 00 p m 54 Using Remote Copy Resuming Production After Failover Returning Operations to Original Primary Site Once the original primary site is operational again restore opera tions to that site The steps to restore operations depend upon the state of the original primary volume e Ifthe primary volume is working Synchronize the data between the acting primary volume and the restored primary volume before returning the acting primary volume to its remote volume state e If the primary volume is not available Create a new primary volume synchronize the data with the acting primary volume and then return the acting primary volume to a remote volume Synchronizing the Data Between the Acting Primary Volume and the Original Primary Volume 1 Create Snapshots of Data Create snapshots that contain the data that you ne
57. lumes 2 and Snapshots 2 BkupLogs 1 Le BkupLogs_SCsnap HaetrsLogs 1 Ha gs on RemExchange im Servers 0 2 Administration Sites RemExchLogs Performance Monitor gt Storage Nodes 1 Volumes 1 and Snapshots 2 RemLogs 2 z amp RemLogs_SS_1 Figure 2 4 Remote copy in progress Creating a Remote Volume Create a remote volume by any of the following methods Designate an existing primary volume as a remote volume See Designating an existing volume as a remote volume on page 20 Create a new remote volume manually See Creating a new remote volume manually on page 20 Create a new remote volume during creation of a remote snapshot See Creating a remote volume on the fly on page 20 Use the Management Groups Clusters and Volumes wizard in Getting Started See Chapter 1 Getting Started in the LeftHand SAN User Manual for details on working through the wizards Using Remote Copy 19 Working with Remote Snapshots Designating an existing volume as a remote volume Selecting an existing volume to become a remote volume causes the following e A scheduled snapshot is created of the volume and then e The volume becomes a 0 byte remote volume See Making a Primary Volume Into a Remote Volume on page 43 Creating a new remote volume manually Create a remote volume as you would any other volume Be sure to choose the storage nodes at the remot
58. me into a primary volume while a remote snapshot is in progress Wait until the remote snapshot copy is complete before making the remote volume into a primary volume or cancel the in progress remote copy 10 Click Finish The snapshot is created and the volume becomes a remote volume The final window of the wizard displays a summary of the actions and a reminder to reconnect your iSCSI sessions as shown in Figure 2 23 48 Using Remote Copy Failover and Failback Using Remote Copy Volume Failover F ailback Wizard X Volume Failover Failback ee a Summary and Reminder to Reconnect Applications Pos gt Volume Failover Summary The following steps were performed to move the primary volume Make a note of the new volume and snapshot names 1 Ensured connected iSCSI sessions were logged off before failover 2 Took a snapshot BkupLogs_FoFb_SS_1 of the primary volume BkupLogs 3 Made the original primary volume BkupLogs a remote volume 4 Copied snapshot BkupLogs_FoFb_SS_1 to the original remote volume RS_BkupLoc 5 Made remote volume RS_BkupLogs an acting primary volume Be sure to reconnect all servers to the new acting primary volume RS_BkupLogs Also reestablish any schedules as needed Figure 2 23 Final summary and reconnect sessions reminder Using Failover to Remote Volume If the primary volume is not available you can use the wizard to promote the rem
59. mote snapshots for high availability configure a backup application server to access remote volumes in the event of a primary system failure Figure 3 1 illustrates this simple high availability configuration e Configure primary and backup application servers in both the primary and backup locations During normal operation the production application server reads and writes to the primary volume e Set up a schedule for copying remote snapshots to the backup location If your application server uses multiple volumes that must be in sync use a script or VSS to quiesce the appli cation before creating remote snapshots Configuration Diagram Application Workstations Clustered a Production Backup Application Application Application Servers Server Read Only Primary Volume Primary Remote Snapshot Snapshot Figure 3 1 High availability example configuration 64 Sample Remote Copy Configurations Using Remote Copy for Business Continuance How This Configuration Works for High Availability If the production application server or volumes become unavail able application processing fails over to the backup application server As shown in Figure 3 2 the remote volume and remote snapshots become acting primary and the backup application server becomes the acting production application server accessing data from the acting primary volume Application Workstations Application Application mal pplicat
60. nly if a group no longer exists or if instructed by Customer Support 60 Using Remote Copy Disassociating Remote Management Groups 1 Log in to both management groups that you want to disassociate 2 Inthe navigation window select the remote management group 3 Click Management Group Tasks and select Edit Management Group The Edit Management Groups window opens shown in Figure 2 31 a Group Hame Exchange Group Mode Normal Mode Local Bandwidth Priority Bandwidth Priority 4 MB sec How Do Set My Bandwidth Priority 0 25 4 10 20 30 40 Max Application Data Access Rebuild Remote Management Groups Management Group Bandwidth to Remote Bandwidth to Primary Connected RemExchange Custom 32768 Kb sec Custom 32768 Kb sec Yes Disassociate Edit Remote Bandwidth Cancel Figure 2 31 Editing a management group 4 Select the management group or groups you want to disasso ciate that is the management groups that are remote relative to this management group 5 Click Disassociate A confirmation message opens describing the results of disassociating the management groups Using Remote Copy 61 Disassociating Remote Management Groups Warning Disassociating the management group cancels any in progress remote snapshots and deletes all timetables between the primary and remote management groups 6 Click OK The Edit Management Group window is displayed on top
61. o the remote management group while creating a remote copy Designating or Creating the Remote Volume Create a remote volume by any of the following methods Make an existing volume into a remote volume Create a new remote volume while creating a remote snapshot Create a new volume from the cluster Details tab window and then select the Remote radio button on the Advanced tab of the New Volume window From the menu bar select Tasks gt Volume gt New Volume For more information about these methods of creating remote volumes see Creating a Remote Volume on page 19 Using Schedules for Remote Copy Scheduled remote snapshots provide fault tolerance for business continuance disaster recovery and provide a consistent predict able update of data for remote backup and recovery Understanding and Planning Remote Copy 9 Using Schedules for Remote Copy Planning the Remote Copy Schedule Recurrence Planning is critical These issues impact the amount of storage available in the system e Recurrence e Capacity e Retention How often do you want the snapshots created The recurrence frequency must account for the amount of time it takes to complete a remote snapshot For example if your recurrence schedule is set for a new snapshot every 4 hours you should ensure that the time to copy that snapshot to the remote location is less than 4 hours Test the time required for copying a snapshot One way to check
62. ot matches its corresponding primary snapshot e Up to two additional snapshots may be retained at any given time Because the SAN iQ software never deletes the last fully synchronized snapshot a remote copy schedule may retain N 2 copies for a retention policy of N the currently copying remote snapshot plus the last fully synchronized snapshot Using the example above if you have a retention policy for your remote copy schedule of 2 primary and 5 remote snapshots the software may retain up to 4 primary and 7 remote snapshots for a period of time Table 1 4 shows the maximum retained snapshots with respect to a specific retention policy Table 1 4 Snapshot retention policy and maximum number of retained snapshots Scheduled Remote Snapshot Maximum Number of Retention Policy Snapshots Retained n of primary snapshots n 2 of primary snapshots X of remote snapshots X 2 of remote snapshots nof hours for primary snapshots n 2 primary snapshots older than n X of hours for remote snapshots X 2 remote snapshots older than x nof days for primary snapshots n 2 primary snapshots older than n x of days for remote snapshots X 2 remote snapshots older than x n of weeks for primary snapshots n 2 primary snapshots older than n x of weeks for remote snapshots X 2 remote snapshots older than x e A remote snapshot is deleted only after its corresponding primary snapshot is deleted Additionally a remote snaps
63. ote Mgmt Group The management group containing the remote volume and snapshot Remote Snapshot The remote snapshot Original Mgmt Group The original management group that contained the original volume and snapshot Used with PrimeSync feature Original Snapshot The first version of the snapshot from which the first copy was created Used with PrimeSync feature Using Remote Copy 33 Monitoring Remote Snapshots Table 2 1 Values for Remote Snapshot Details window Continued Statistic Values Status Manual Scheduled Whether the snapshot was created manually or with a scheduled snapshot State Started Copying Stalled Complete Current state of the copy process Snapshot Scanned 0 100 Percent of the copy process that is completed Time Start Time MM DD YYYY HH MM SS AM PM Time Zone Date and time copy started Elapsed Time Xd Xh Xm Xs X a number and the days hours minutes and seconds the copy has been processing N A if not yet available Est Time Remaining Xd Xh Xm Xs X a number and the days hours minutes and seconds estimated to remain in the copy process N A for completed copies or in progress copies not yet calcu lated Completion Time MM DD YYYY HH MM SS AM PM Time Zone Date and time copy completed N A for in progress copies Data Data Copied MB GB or TB Amount of data copied so far in smallest unit size Data Rema
64. ote volume to an acting primary volume 1 In the navigation view select the volume that you want to convert 2 Right click and select Failover Failback Volume The Volume Failover Failback wizard opens shown in Figure 2 24 Using Remote Copy 49 Failover and Failback Using Remote Copy Volume Failover Failback Wizard Volume Failover Failback Wizard This wizard helps you to move your primary volume when backing up your data failing over to a remote volume and failing back to a primary volume This wizard can be beneficial when moving a data center or preparing for business continuance and disaster recovery The wizard helps you Log off connected iSCSI sessions e Make the original primary volume a remote volume a snapshot of the primary volume will be taken automatically Copy the snapshot to the remote volume Make the remote volume an acting primary volume LeftHand poteto Remember to log on to the iSCSI sessions and Solel reso reestablish schedules Before you start this wizard you must Log off connected iSCSI sessions wow lefthandnetworks com accessing the original primary volume To exit click Cancel at any time To continue click Next Figure 2 24 Opening the Volume Failover Failback wizard 3 Click Next You next select the reason you are failing over the volume shown in Figure 2 25 e Use the second choice if your primary volume is not ava
65. pshots and scheduling snapshots e Configuration of application servers and backup application servers e Task flow for failback resuming production after failover Using Scripting for Failover Application based scripting provides the capability for creating mounting and deleting snapshots using scripts Remote Copy can be scripted as well Remote snapshots and scheduled remote snapshots can be created and managed using scripts Find infor mation about scripting in the CLIQ The SANiQ Command Line Interface User Manual and in sample scripts available on the LeftHand Networks website Using the Volume Failover Failoack Wizard Changing the roles of primary and remote volumes may be necessary during failover and failback Move your primary volume either as part of a failover failback scenario or as part of a planned move The Volume Failover Failback wizard takes you 42 Using Remote Copy Failover and Failback Using Remote Copy through the necessary steps to move a primary volume to an existing remote volume and to promote the existing remote volume to an acting primary volume Later when failing back or restoring operations in a planned move resynchronize data between the acting primary and the recovered or newly configured production site primary volume Note When failing over a primary volume the volume Note must have a remote copy relationship to use the wizard Making a Primary Volum
66. py this volume to a location where application servers can access it more effi ciently Sample Remote Copy Configurations 71 Using Remote Copy for Business Continuance Application Workstations Production Application Application Servers Read Only Mi Remote i Volume Storage Subnet Primary Snapshot Snapshot Backup Site Production Site Figure 3 6 Restoring from a remote volume In Figure 3 6 note the volume labeled Primary Snapshot in the gray area on the left It originated as a read only back up but is brought into use as an acting primary Application Workstations Lo J Production Production Application Application Application Servers Primary Kd Remote f x Remote Primary iVolume 1 i Volume 2 i Volume Storage Primary Remote Remote Primary Snapshot Snapshot 1 Snapshot 2 Snapshot Production Site 1 Backup Site Production Site 2 Figure 3 7 Restoring from tape backup 72 Sample Remote Copy Configurations Using Remote Copy for Business Continuance Best Practices Select an optimum recurrence schedule Select a recurrence schedule for remote snapshots that minimizes the potential for data loss Any data written to the primary volume since the most recent remote snapshot was created will be unavailable if the primary volume is unavailable Consider how much data you are willing to lose in the event of an emergency and set the recurrence for creatin
67. r to the remote volume This can be a manual operation a scripted operation or VMware enabled Acting Primary Volume The remote volume when it assumes the role of the primary volume in a failover scenario Original Primary Volume The primary volume that fails and then is returned to service Failback After failover the process by which you restore the primary volume and turn the acting primary back into a remote volume Failover Recovery After failover the process by which the user chooses to fail back to the primary volume or to make the acting primary into a permanent primary volume 2 Understanding and Planning Remote Copy How Remote Copy Works Table 1 1 Remote Copy Glossary Continued Term Definition Synchronize The process of copying the most recent snapshot from the primary volume to a new remote snapshot On failback syn chronization is the process of copying the most recent remote snapshot back to the primary volume The CMC displays the progress of this synchronization Also you can manually synchronize if necessary to include data that is on the remote volume but not the primary Split Mirror A split mirror is a remote snapshot whose relationship to the primary volume has been severed Split mirrors are usually created for one time use and then discarded How Remote Copy Works Reproducing data using Remote Copy follows a three step process
68. rage node failure Example Configuration e Inthe production location create a cluster of 3 storage nodes all with managers e Create volumes on the cluster and set the replication level to 2 Way e Create a schedule for making remote snapshots of the primary volume Set the recurrence to every 4 hours and retention of remote snapshots to 2 days Note You can use the same volume replication configuration on the remote volume as well However this replication is configured independently of the volume replication that is configured on the primary volume Note If one of the storage nodes in the primary location fails the primary volume will still be available If all of the storage nodes fail or if the application server fails then you can recover data from the remote snapshots or tape backups in the off site location Using Remote Copy for Off site Backup and Recovery For backup and recovery systems Remote Copy can eliminate the backup window on an application server Using iSCSI command line interface commands and scripts configure the iSCSI initiator to mount remote snapshots on a backup server either local or remote and then back up the remote snapshot from the backup server The remote snapshot is available if the primary volume fails 74 Sample Remote Copy Configurations Using Remote Copy for Off site Backup and Recovery Achieving Off site Backup Rather than creating tape backups and then transpor
69. ring to receive email notification or for SNMP traps The Remote Copy variables that are monitored include these e Remote Copy status an alert is generated if the copy fails e Remote Copy complete an alert is generated when the remote copy is complete e Remote Copy failovers an alert is generated when a remote volume is made primary e Remote management group status an alert is generated if the connection to a remote management group changes dis connects and or reconnects Using Remote Copy 35 Scheduling Remote Snapshots To read about configuring Active Monitoring see the Reporting chapter of the LeftHand SAN User Manual Scheduling Remote Snapshots In addition to taking remote snapshots of a volume manually you can set up a schedule to take snapshots and save them remotely Scheduled remote snapshots provide for business continuance and disaster recovery as well as provide a consistent predictable update of data for remote backup and recovery Planning for scheduled remote snapshots is a crucial initial step in implementing Remote Copy The following items require planning in advance for successful deployment of scheduled remote snapshots e Recurrence frequency e Retention policies e Capacity planning e Timing For detailed information about these issues see Planning for Remote Copy on page 8 Best Practices for Scheduling Remote Snapshots e Create anew remote volume to use with th
70. rocess of copying the data may take some time The remote snapshot appears below the remote volume in the navigation window as shown in Figure 2 5 aie Note If you create a remote snapshot of a volume with a remote snapshot still in progress the second remote snapshot does not begin copying until the first remote snapshot is complete Using Remote Copy 21 Working with Remote Snapshots Figure 2 5 Viewing Creating the First Copy gt LeftHand Networks Centralized M E Getting Started yt Configuration Summary oS Exchange 5 Servers 1 SS Administration Sites G ExchLogs a Performance Monitor Storage Nodes 3 gt Denver 1 Denver 2 gt Denver 3 amp Volumes 2 and Snapshots 2 BkupLogs 1 BkupLogs_SCsnap E HadtrsLogs 1 G eT GH RemExchange Servers 0 Se Administration Sites S RemExchLogs Performance Monitor s Storage Nodes 1 Eal volumes 1 and Snapshots 2 RemLogs 2 RemLogs_SS_1 the remote snapshot Creating the first copy of data is the first step when setting up a Remote Copy solution Three methods for creating the first copy are described below Copy data directly to the remote site over the WAN Use this method if you are implementing the Remote Copy solution before you have accumulated much data in the primary site and your hardware is already installed in the remote site In this method you cr
71. sing Remote Copy Resuming Production After Failover volume and configure the timetable for the scheduled remote snapshot schedule on the new primary volume 1 Stop the application that is accessing the acting primary volume Create a remote snapshot of the acting primary volume As your target create a remote volume which will later be converted into your primary volume Convert the remote volume into a primary volume Make the acting primary volume into the remote volume This creates a snapshot of that volume Configure a new timetable for the scheduled remote snapshots on the new primary volume Reconfigure scripts for failover on the application servers Setting Up a New Production Site Setting up a new production site involves creating a new primary volume and synchronizing the acting primary volume before returning it to its original state as a remote volume The steps are the same as those for creating a new primary volume at the original production site Making the Backup Site into the New Production Site Turn the backup site into the new production site and designate a different backup site The steps are similar to those for initially configuring Remote Copy 1 Create a remote snapshot or a timetable for a scheduled remote snapshot on the acting primary volume Make a new remote volume on the new backup site as part of creating that remote snapshot or timetable for a scheduled remote snapshot
72. the fly 20 using an existing 20 Resuming Scheduled Snapshots 39 Retention Policy for Remote Snapshots 72 Rolling Back a Volume Remote Copy and primary volumes 58 59 87 Remote Copy and remote volumes 59 S Scheduled Snapshots 37 41 pausing or resuming 39 Schedules Planning Remote Copy 13 Scheduling remote snapshots 36 39 Scripting for Failover 42 Setting Remote Bandwidth 25 Snapshots deleting schedules 39 40 pausing or resuming 39 scheduling 37 41 Snapshots See also Primary Snapshots Remote Snapshots Split mirrors creating 60 Synchronizing Data after failover 54 after failover between acting primary volumes and original primary volumes 55 T Timeline of failover 54 U Uses for Remote Copy 6 Using Remote Copy for Business Continuance 63 for Data Migration 82 for Off Site Backup and Recovery 74 V Viewing a List of Remote Snapshots 24 Volume Type changing primary into remote 43 Volumes cloning 7 cloning and data migration 82 synchronizing data after failover 55 Volumes See also Primary Volumes Remote Volumes 88
73. ting them to a secure off site location you can use Remote Copy to create remote snapshots in an off site location Then optionally you can create tape backups at the off site location Configuration for Off site Backup and Recovery To use remote snapshots for off site tape backup create remote snapshots for access by your tape backup application e Create remote volumes in your backup location e Configure your backup application to access the remote snap shots e Configure schedules to create remote snapshots in the desig nated off site locations If your application server uses multiple volumes that must be in sync use a script to quiesce the application before creating remote snapshots e Optional Create routine tape backups of the remote snap shots See the example configuration illustrated in Figure 3 8 Sample Remote Copy Configurations 75 Using Remote Copy for Off site Backup and Recovery Configuration Diagram Application Workstations Ethernet Corporate LAN 2 Production i i Production Application Application Server Application Servers Read Only Read Only Primary fs Sed Remote H 4 Remote Primary Volume i Volume 1 i Volume 2 Volume Storage Soraperes ar Subnet Primary Remote Remote Primary Snapshot Snapshot 1 Snapshot 2 Snapshot Production Site 1 Backup Site Production Site 2 Figure 3 8 Off site backup and recovery example configuration How This Config
74. ts on page 36 What the System Does Best Practice If you created a new volume for the remote volume the system creates a new primary snapshot of the primary volume and a remote snapshot of the remote volume See Best Practices for Scheduling Remote Snapshots on page 36 38 Using Remote Copy Scheduling Remote Snapshots If you selected an existing volume to become the remote volume the system alerts you that all the data on the existing volume will be deleted but that a snapshot of all the existing data will be created first The snapshot that is then created retains all the volume s data 1 Type a name for that snapshot in the alert 2 Click Yes to continue The new snapshot is created and the volume becomes a remote volume The system creates a new primary snapshot of the primary volume and a remote snapshot of the remote volume It then copies the data from the primary snapshot to the remote snapshot This process occurs according to the schedule Pausing and Resuming Scheduled Snapshots At times it may be convenient to prevent a scheduled snapshot from taking place Use these steps to pause and then resume a schedule to snapshot a volume When you pause a snapshot schedule the snapshot deletions for that schedule are paused as well When you resume the schedule both the snapshots and the snapshot deletions resume according to the schedule Pause a Schedule 1 Inthe navigation window select t
75. twork bandwidth required for configuring hot backup sites you can still use Remote Copy to protect your data during an emergency Using remote snapshots you can maintain copies of your volumes in remote sites Set up a schedule for creating remote snapshots and if your primary storage site becomes unavailable you can easily access the most recent remote copy of your data volumes You can also use remote snapshots to transfer data to a backup location where tape backups are then created This elimi nates the backup window on your primary volumes and ensures that you have copies of your data in the remote site on storage nodes as well as on tape Sample Remote Copy Configurations 69 Using Remote Copy for Business Continuance Configuration for Affordable Disaster Recovery To configure affordable disaster recovery create remote snapshots of your volumes in an off site location In addition you can create tape backups from the remote snapshots in the off site location Designate one or more off site locations to be the destination for remote snapshots Set up a schedule for creating remote snapshots in the desig nated off site locations If your application server uses multiple volumes that must be in sync use a script to quiesce the application before creating remote snapshots Create routine tape backups of the remote snapshots in the off site locations Figure 3 5 shows an example configuration for disaster recover
76. uration Works for Off site Backup Depending on how long you retain the copies of the remote snap shots you can retrieve data directly from recent remote snapshots rather than going to tape backups Otherwise retrieve data as you normally would from the tape backup Best Practices Retain the most recent primary snapshots in the primary cluster By keeping snapshots on your primary volume you can quickly roll back a volume to a previous snapshot without accessing off site backups e When you create a schedule for Remote Copy you specify a number of primary and remote snapshots that you want to retain You can retain primary snapshots to facilitate easy rollback of the primary volume Retention of snapshots will affect the amount of space that is used in the cluster of storage nodes so balance the number of snapshots to retain 76 Sample Remote Copy Configurations Using Remote Copy for Off site Backup and Recovery with the amount of space you are willing to use To roll back to a snapshot that you did not retain you can still access remote snapshots or tape backups e Retain remote snapshots in the backup location to facilitate fast recovery of backed up data If you retain a number of remote snapshots after a tape backup is created you can access these data without going to the backup tape Example Configuration e Retain 3 primary snapshots This enables you to roll the primary volume back yet it requires a relat
77. y Application Workstations aga Ethernet Corporate LAN Production Application Server Production Application Application Servers Read Only Remote i Volume 2 Primary Volume Primary i Volume 1 i Remote Remote Snapshot 1 Snapshot 2 Backup Site Storage Subnet Primary Snapshot Primary Snapshot Production Site 1 Production Site 2 Figure 3 5 Affordable disaster recovery example configuration 70 Sample Remote Copy Configurations Using Remote Copy for Business Continuance How This Works for Affordable Disaster Recovery If the storage nodes in your primary location fail or volumes become unavailable the off site location contains the most recent remote snapshots Use the remote snapshots to resume operations as shown in Figure 3 6 If you created tape backups you can recover data from tape backups as shown in Figure 3 7 Only data written to the primary volumes since the last remote snapshot was created will be unavailable Application servers that were accessing the offline volumes will not be available until you reconfigure them to access recovered data To resume operations using the most recent set of remote snap shots 1 In the backup location make the remote volume into a primary volume Configure application servers to access this volume or if network connections are not fast enough to facilitate reading and writing to the off site location co
78. ync look for the Application Note SAN iQ Remote Copy PrimeSync Creating Initial Copy in the Customer Resource Center Viewing a List of Remote Snapshots View a list of remote snapshots associated with management groups clusters volumes or snapshots 1 In the navigation window select the cluster for which you want to view the list of remote snapshots Click the Remote Snapshot tab to bring it to the front shown in Figure 2 6 The report in the tab window lists management groups and all the snapshots The other columns show status information about the remote snapshots as described in detail in Monitoring Remote Snapshots on page 30 24 Using Remote Copy Working with Remote Snapshots Details I Use Summary Volume Use Node Use iSCSI Sessions I Remote Snapshots iSCSI Primary Ma Primary Sn Remote Ma Remote Sn Complete Elapsed Time Data Copied Rate State Exchange HdqtrsLog RemExcha RemLogs_ 1m 22s 247 MB 24 675 Kbi Complete Exchange HagtrsLog RemExcha RemLogs_ MENEEPS 1 am 17s 672 25MB 27 954 Kbi Copying Figure 2 6 Viewing the list of remote snapshots Setting the Remote Bandwidth The remote bandwidth sets the maximum rate for data transfer between management groups That is the copy rate is equal to or less than the rate set To control the maximum rate of data transfer to a remote snapshot set the remote bandwidth on t

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LeftHand Networks® Remote Copy User Guide