Cisco Systems 17053 Switch User Manual
Contents
1. Network Infrastructure Getting Started with LANs Related Information e Configuring and Troubleshooting Ethernet 10 100 1000Mb Half Full Duplex Auto Negotiation e LAN Product Support Pages e LAN Switching Technology Support e Technical Support amp Documentation Cisco Systems All contents are Copyright 2006 2007 Cisco Systems Inc All rights reserved Important Notices and Privacy Statement Updated Aug 30 2005 Document ID 170532. 24PWR inline power interfaces do not link up to certain 10 100 1000 interfaces configured as auto auto To connect the 12 1 13 EA1 Catalyst 3550 24PWR inline power interfaces to a 10 100 1000 interface configured as auto auto on a Catalyst 3550 12G or 3550 12T does not work CSCdz44520 registered customers only CSCdz32789 eged The link to certain NICs fails to come up when the switch port is 12 1 13 EA1 hardcoded to 100 Mbps full duplex or 100 Mbps customers only CSCdy72718 E registered The switch port does not receive customers only packets if the port is hardcoded to a speed of 100 however it va TOOB BE oti the Catalyst 3550 24PWR switch is CSCea36322 connected to a Gigabit Ethernet c registered NIC with the speed duplex customers only setting set to auto and the port Ka AEA speed changed from 100 Mbps to 10 Mbps or from 10 Mbps to 100 Mbps the link between the port and the NIC can potentially not come up 12 1 13 EA1 For detailed information on Cisco bug IDs refer to the Bug Toolkit i registered customers only NIC Compatibility and Operation Issues Disclaimer Use this table as a guide in order to troubleshoot NIC issues Consult the NIC vendor for verification and proper resolution of the issue Table 11 NIC Model Manufacture eee eet Dee ate Apple Macintosh G3 Apple Macintosh Power Macintosh G3 and Powerbook G3 Apple Macintosh OS with Open Tr
3. When operating at a half duplex setting some data link errors such as FCS alignment runts and collisions are normal Generally a one percent ratio of errors to total traffic is acceptable for half duplex connections If the ratio of errors to input packets is greater than two or three percent performance degradation can be noticed In half duplex environments it is possible for both the switch and the connected device to sense the wire and transmit at exactly the same time and result in a collision Collisions can cause runts FCS and alignment errors caused when the frame is not completely copied to the wire which results in fragmented frames When operating at full duplex FCS cyclic redundancy checks CRC alignment errors and runt counters are probably minimal If the link operates at full duplex the collision counter is not active If the FCS CRC alignment or runt counters increment check for a duplex mismatch Duplex mismatch is a situation in which the switch operates at full duplex and the connected device operates at half duplex or the other way around The result of a duplex mismatch is extremely slow performance intermittent connectivity and loss of connection Other possible causes of data link errors at full duplex are bad cables a faulty switch port or NIC software or hardware issues When you troubleshoot NIC performance issues view the output of the show port mod port command and the show mac mod por
4. duplex on only one link partner are more common Because of these recent issues the use of autonegotiation is regarded as a valid practice EtherChannel and Trunking Between Catalyst Switches and NICs EtherChannel can be configured dynamically with Port Aggregation Protocol PAgP and trunking can also be configured dynamically with Dynamic Trunking Protocol DTP Both PAgP and DTP are Cisco proprietary protocols and supported only on Catalyst switches If you want to configure EtherChannel or trunking between Catalyst switches and NICs it is recommended that you configure these features statically as other vendor NICs can potentially not support PAgP and DTP On Catalyst switches configure the EtherChannel mode to on and trunking mode to nonegotiate which disables the PAgP and DTP protocols If you configure the switch port with auto or desirable mode it is possible you can not be able to form the EtherChannel or trunk with NICs Verifying Physical Connection and Link When you troubleshoot NIC issues the first step is to verify physical connectivity Visual inspection of the switch must show a LINK light indicator when connected to a link partner In addition the NIC can also have a LINK light indicator The Command Line Interface CLI of the switch must be checked in ordre to verify physical connectivity The port in question must show connected for Catalyst OS software and line protocol up for Cisco IOS Software on the switch Exa
5. PORTFROMSTP Port 3 3 left bridge port 3 3 PAGP 5 PORTTOSTP Port 3 3 joined bridge port 3 3 e For Cisco IOS Software based switches these messages appear for link up down situations oe oe LINK 3 UPDOWN Interface interface changed state to up LINK 3 UPDOWN Interface interface changed state to down oe This is an example oe LINK 3 UPDOWN Interface FastEthernet0 1 changed state to up LINK 3 UPDOWN Interface FastEthernet0 1 changed state to down oe In order to resolve these issues troubleshoot with these techniques e Disable Windows 2000 and Windows Millennium Edition ME power management functions Windows 2000 and Windows ME employ a power management capability that can disable the NIC When the NIC is disabled for power management it drops the link to the switch If there is a concern about the link going up down on NICs with the Windows 2000 or Windows ME operating systems disable the power management feature as a first step in order to troubleshoot link up down situations e Disable the NIC power management functionality Many NICs support their own power management capability When you troubleshoot link up down issues disable this feature For information on how to disable power management refer to the NIC documentation e Adjust switch jitter tolerance Jitter tolerance based on the IEEE 802 33u 1995 clause 25 must not exceed 1 4 nanoseconds However there are situations in which N
6. a port replicator or docking station Certain 10 100 switches implement automatic correction for polarity reversed cables that are not completely compatible with the same correction provided by the CBE RBE If the network speed is forced to 10 Mbps severe throughput problems can be experienced Initialization delay Certain switches and routers are unable to immediately forward network traffic when a network adapter first establishes link to one of its ports because of initialization delays This problem is most commonly seen when the network adapter is connected directly to ports on the switch The adapter by default when used under some operating systems has almost no delay between link and the initial network request Possible Basic Input Output System BIOS or driver update required Contact vendor support for more information type keyword can be set to Auto Detect or 10BASE T 100BaseTX The related port on the attached hub or switch must also be set to 10Mbps full duplex In order to resolve this problem a new Auto Polarity keyword is added in the adapter advanced properties in driver version 3 01 If needed the default setting of ON which means that the card compensates for reversed cables can be set to OFF to disable polarity correction normal throughput A new keyword Initialization Delay is added to the adapter advanced properties that prevents forwarding of netwo
7. and frame check sequence FCS errors that increment on the switchport In order to troubleshoot this issue try to manually configure the switchport to 100 Mbps half duplex If this action resolves the connectivity problems this NIC issue is the possible cause Try to update to the latest drivers for your NIC or contact your NIC card vendor for additional support Why Is It That the Speed and Duplex Cannot Be Hardcoded on Only One Link Partner As indicated in Table 1 a manual setup of the speed and duplex for full duplex on one link partner results in a duplex mismatch This happens when you disable autonegotiation on one link partner while the other link partner defaults to a half duplex configuration A duplex mismatch results in slow performance intermittent connectivity data link errors and other issues If the intent is not to use autonegotiation both link partners must be manually configured for speed and duplex for full duplex settings Recommended Port Configuration Autonegotiation or Manual Configuration There are many opinions on the subject of autonegotiation Previously many engineers advised customers not to use autonegotiation with any switch connected device However improvements in the interoperation of autonegotiation and the maturity of the technology has recently changed the view of autonegotiation and its use In addition performance issues due to duplex mismatches caused by the manual setting of speed and
8. duplex is half duplex unless the 0 8 is programmed to 1 which represents full duplex Based on IEEE 802 3u it is not possible to manually configure one link partner for 100 Mbps full duplex and still autonegotiate to full duplex with the other link partner If you attempt to configure one link partner for 100 Mbps full duplex and the other link partner for autonegotiation it results in a duplex mismatch This is because one link partner autonegotiates and does not see any autonegotiation parameters from the other link partner and defaults to half duplex As described in Appendix B Understanding How Autonegotiation Works pulses within the FLP are used to derive code words that exchange link partner capabilities The first code word exchanged is referred to as the base page It informs each link partner of the message type IEEE 802 3 or IEEE 802 9a and a technology ability field This technology ability field is encoded to exchange the maximum operational speed and duplex of each link partner Networking Professionals Connection Featured Conversations Networking Professionals Connection is a forum for networking professionals to share questions suggestions and information about networking solutions products and technologies The featured links are some of the most recent conversations available in this technology NetPro Discussion Forums Featured Conversations for LAN Network Infrastructure LAN Routing and Switching
9. four ports V1 1 can potentially not establish link to Full duplex operation is only supported at 10 Mbps Full duplex is not supported at 100 Mbps The LineMode keyword has no effect on performance at 100 Mbps If the LineSpeed keyword is set to 100 Mbps and the LineMode keyword is set to full duplex the LineMode keyword is ignored Full duplex at 10 Mbps is only available when the adapter is connected toa full duplex capable switch or hub The CE3 and in some cases the CE3B are not capable of negotiating to 10 Mbps full duplex mode Contact vendor technical support to obtain the latest driver to resolve the issue Contact vendor technical support or v2 0 Gigabit Do not operate this NIC at 100 Mbps full duplex On these adapters in order to operate in full duplex mode the LineSpeed keyword must be set to 10 Mbps and the LineMode keyword must be set to full duplex The cable Xircom RealPort2 CardBus Ethernet 10 100 Adapter R2BE RBE CBE Models Xircom RealPort2 CardBus Ethernet 10 100 Adapter R2BE RBE CBE Models Xircom RealPort2 CardBus Ethernet 10 100 Adapter R2BE RBE CBE Models Extremely slow performance when operating at 10 Mbps Initial network connections can fail DHCP can obtain an IP address and Windows NT login and Novell IPX can fail Not able to connect to the network or get an IP address from the DHCP server when connected to
10. only frames after a scheduled test of the packet buffers The workaround is to disable the packet buffer test The WS X5225R and WS X5234 modules fail to negotiate the 4 5 7 5 4 2 duplex mode correctly after a system reset or power cycle with Sun workstations Ultra 5 CSCdm51653 4 5 3 5 1 2a Autonegotiation registered customers only between Sun 10 100 NICs and certain Catalyst 5000 family modules such as the CSCdt28585 registered customers only CSCdr03818 registered customers only WS X5225R can result in speed or duplex mismatches under certain conditions The problem typically occurs after the module is reset or the switch port is disabled and reenabled The workaround is to disconnect and reconnect the cable that connects the workstation to the switch port The 48 port 10BASE T Ethernet module WS X5012 incorrectly drops valid frames with dribble bits extra bits added to frames by some end stations and transceivers CSCdk32984 registered customers only 4 2 2 Under heavy traffic conditions ports 1 CSCdj82035 through 24 or ports 25 registered customers only through 48 of the a 48 port 10BASE T Ethernet module WS X5012 can stop transmitting frames For detailed information on Cisco bug IDs refer to the Bug Toolkit ET registered customers only Refer to Cisco Catalyst 5000 Series Switches Release Notes for more Catalyst 5000
11. placement within the 16 bit register Table 12Physical Interface PHY Control Register Programmable Options 1 PHY reset 0 normal mode 1 loopback mode switched on Loopback 0 loopback mode switched off 0 6 0 13 Rate Selection 1 1 reserved least significant bit LSB 1 0 1000 Mbps 0 1 100 Mbps 0 0 10 Mbps 1 autonegotiaton enabled Autonegotiation Enable 0 autonegotiation disabled 1 power down Power Down 0 normal down 1 PHY electrically isolated 0 10 from media independent Isolated interface MID 0 normal mode 1 restart the autonegotiation process Restart Autonegotiation 0 normal mode 1 full duplex Duplex Mode 0 half duplex 1 collision COL signal test Collision Test ANE 0 COL signal test switched off Rate Selection most significant bit MSB See bit 0 13 The register bits relevant to this document include 0 13 0 12 0 8 and 0 6 The other register bits are documented in the IEEE 802 3u specification Based on IEEE 802 3u in order to manually set the rate speed the autonegotiation bit 0 12 must be set to a value of 0 As a result autonegotiation must be disabled in order to manually set the speed and duplex If the autonegotiation bit 0 12 is set to a a value of 1 bits 0 13 and 0 8 have no significance and the link uses autonegotiation to determine the speed and duplex When autonegotiation is disabled the default value for
12. port on which the packet is received Lrn Discard This counter must remain at zero If counter increments create a service request with Cisco In Lost Excessive output rate of traffic Increments in this counter are more likely to occur when connected Out Lost to low speed devices The first step to troubleshoot Out Lost increments is to verify the link partner runs 100 Mbps full duplex without any errors aa 2 In Discard and Lrn Discard do not exist on all Catalyst platforms Additional counter information can be viewed with the command show counters mod port The command must be issued for a single port at a time Refer to this document for information on the counter displayed e show counters Command Documentation For additional information about the Cisco IOS Software show interfaces command counters refer to e show interfaces Command Documentation Sniffer Trace Sniffer trace analysis can be very useful when you troubleshoot switch and NIC performance or connectivity issues when the issues persist after all other sections of this document are reviewed Sniffer trace analysis reveals every packet on the wire and pinpoints the exact problem It can be important to obtain several sniffer traces from different ports on different switches Generally it is very useful to monitor or span ports rather than spanning VLANs when you troubleshoot switch and NIC performance and connectivity issues Refer to
13. Catalyst Switched Port Analyzer SPAN Configuration Example for more information on the use of the Switched Port Analyzer SPAN feature required to obtain sniffer traces Teaming of Network Interface Cards Teaming of Network Interface Cards or NIC Teaming can cause instability in the networks Such setups can introduce disruptions to the Spanning tree and can make it undergo frequent recomputations If intermittent loss of connectivity to NIC teamed servers occurs for devices or hosts in the same VLAN try to disable NIC teaming If the connectivity stabilizes refer to the NIC vendor documentation in order to tune the NIC teaming configuration Additional Troubleshooting for 1000BASE X NICs Gigabit Autonegotiation No Link to Connected Device Gigabit Ethernet has an autonegotiation procedure that is more extensive than what is used for 10 100 Mbps Ethernet Gigabit autonegotiation specification IEEE 802 3z 1998 The Gigabit autonegotiation negotiates flow control duplex mode and remote fault information You must either enable or disable link negotiation on both ends of the link Both ends of the link must be set to the same value or the link does not connect If either device does not support Gigabit autonegotiation disable Gigabit autonegotiation in order to force the link up The default configuration of all Cisco switches is autonegotiation enabled If you disable autonegotiation it hides link drops and other physical layer probl
14. Cs Catalyst 8510 and 8540 CSR In the campus switch router CSR Cisco IOS Software Release 12 0 5 W5 13 autonegotiation for speed and duplex are enabled by default In earlier releases autonegotiation is not supported by default As a result each connected interface must be set to run in full duplex mode If you upgrade to Cisco IOS Software Release 12 0 5 W5 13 with a router that runs in manually full duplex mode you experience performance issues The symptoms include high collision rate reduced throughput and more packet drops This is because the Catalyst 8500 waits to autonegotiate with the connected device Now that the connected device is forced to run in full duplex mode it does not participate in autonegotiation Based on the specification this causes the Catalyst 8500 interface to settle in half duplex mode which causes a mismatch between the device and the Catalyst 8500 at the interface level Catalyst 8500 interface defaults to half duplex mode when the peer is incapable of negotiation Catalyst 6000 and 6500 Switches This table describes Cisco bug IDs found on the Catalyst 6000 and 6500 switches Table 7 Cisco Bug ID Resolved owt Description When a port goes into the errdisable state on a Catalyst 6000 or 6500 the switch inadvertently learns the MAC CSCdm48887 addresses of other devices to be registered learned from the errdisable customers only 2 port The errdisable state is caused by excessive l
15. ICs that operat out of specification with respect to excessive jitter cause link up down situations on Catalyst 6000 and 6500 10 100 ports The workaround for this issue is to increase the jitter tolerance on the Catalyst 6000 and 6500 switches for 10 100 ports to 3 1 seconds The set option debounce enable command enables the feature As an ultimate solution replace the out of specification NICs instead of using the debounce option This feature is first integrated into software version 5 3 5 CSX For the Catalyst 2900XL and 3500XL the interface command carrier delay time can be adjusted to four seconds as a possible workaround for this same issue Refer to Fast Ethernet Consortium Physical Medium Dependent Test Suite for more information about jitter tolerance Performance Notes Most performance issues are related to switch port configuration duplex mismatches link up down situations and data link errors When you troubleshoot performance issues review all previous sections of this document After you review these sections proceed to the next section Understanding Data Link Errors The final step in order to resolve any performance issue is to obtain a sniffer trace A sniffer trace is very conclusive with regard to any specific performance problem because it details packet transfer Understanding Data Link Errors Many performance issues with NICs can be related to data link errors Excessive errors usually indicate a problem
16. Troubleshooting Cisco Catalyst Switches to NIC Compatibility Issues Document ID 17053 Introduction Prerequisites Requirements Components Used Conventions Background Information Purpose Why Do Autonegotiation and Compatibility Issues Exist General Troubleshooting for 10 100 1000 Mbps NICs Autonegotiation Valid Configuration Table EtherChannel and Trunking Between Catalyst Switches and NICs Verifying Physical Connection and Link Verifying Switch Port Configuration Maintaining Link Link Up Down Situations Performance Notes Understanding Data Link Errors Sniffer Trace Teaming of Network Interface Cards Additional Troubleshooting for 1000BASE X NICs Gigabit Autonegotiation No Link to Connected Device Verifying GBIC Cisco Catalyst Switch Compatibility and Operation Specific Issues Catalyst 8510 and 8540 CSR Catalyst 6000 and 6500 Switches Catalyst 5000 and 5500 Switches Catalyst 4000 2948G and 2980G Switches Catalyst 2950 and 3550 Switches NIC Compatibility and Operation Issues Appendix A Information to Gather Before Creating a Service Request Appendix B Understanding How Autonegotiation Works Networking Professionals Connection Featured Conversations Related Information Introduction The purpose of this document is to cover common issues associated with network interface cards NICs that interoperate with Cisco Catalyst switches Network issues such as slow performance and connectivity problems as well as Catalyst switch
17. ablished but switch does not see any autonegotiation information from NIC and defaults to half duplex when operating at 10 100 Mbps Link is established but 10 Mbps switch does not Half duplex 10 Mbps 10 Mbps see Fast Link Half duplex Half duplex Pulse FLP and defaults to 10 Mbps half duplex 100 Mbps Half duplex 100 Mbps 100 Mbps Half duplex Half duplex 10 Mbps Neither side Half duplex 100 Mbps establishes link Half duplex EE ROE due to speed mismatch Link is established but NIC does not see any autonegotiation information and defaults to 100 Mbps half duplex Link is established but NIC does not see FLP and defaults to 10 Mbps half duplex 100 Mbps 100 Mbps 100 Mbps Half duplex Half duplex Half duplex 10 Mbps 10 Mbps 10 Mbps Half duplex Half duplex Half duplex LA duplex mismatch can result in performance issues intermittent connectivity and loss of communication When you troubleshoot NIC issues verify that the NIC and switch use a valid configuration 2 Some third party NIC cards can fall back to half duplex operation mode even though both the switchport and NIC configuration are manually configured for 100 Mbps full duplex This is because NIC autonegotiation link detection still operates when the NIC is manually configured This causes duplex inconsistency between the switchport and the NIC Symptoms include poor port performance
18. and 5500 documented bug fixes Catalyst 4000 2948G and 2980G Switches This table lists several known issues found on the Catalyst 4000 2948G and 2980G switches Table 9 CSCds38973 14 5 8 The Catalyst 2948G and Catalyst 5j registered 5 2 7 4000 switches can experience issues customers only 5 5 2 with total or intermittent loss of connectivity The frequency of these issues can vary from once a CSCdr37645 registered customers only CSCdm38405 a registered customers only CSCdm51653 registered customers only CSCdt80707 registered customers only day to once a month This issue can reoccur even after the switch is power cycled The purpose of this Cisco bug ID is to combine several software reworks fixes that resolve and reduce the loss of connectivity issues and additional troubleshooting checks in software An invalid packet with a length of less than 64 bytes received on a 10 100 port causes both the Runts and FCS Error counters to increment on the port To determine the actual number of FCS Errors on valid length packets received on the port subtract the value of the port Runts counter from the value of the port FCS Error counter Some Sun Gigabit Ethernet NICs do not reliably autonegotiate flow control with certain ports on the Catalyst 4000 series oversubscribed Gigabit Ethernet modules The 18 port server switching 1000BASE X GBIC Gigabit Et
19. ansport 2 5 1 and 2 5 2 Apple Macintosh Built In Ethernet Apple Macintosh Performance Issues and NuBus Apple Powerbook G3 G4 with Internal NIC Various Apple G3 G4 Laptops and Workstations with Internal NICs Intermittently loses network services when the built in Ethernet interface is used Unable to set speed and duplex of built in Ethernet interface manually Kona to obtain DHCP s server Unable to determine hardware MAC address Built in Ethernet interfaces outperform NuBus Ethernet cards Slow performance when large file transfers are performed Driver versions earlier than 2 04 can experience this issue Contact vendor technical support for more information Apple Speed Duplex tool is required to manually set Ethernet interface Upon bootup ees can fail to server trou HCP network See ek issues host MAC address can be required Concern of maximum data transfer rate possible with the operate out of specification as published in IEEE 802 3 Some Catalysts are more tolerant of out of spec NICs and do not notice any performance degradation Notable slow performance Upgrade to driver version 2 04 or later Download Apple aes tool from article esata Contact vendor technical support See Apple technical information library Use of external or PC card Contact Apple technical support Upgrade to latest NIC driver and load Duplexer u
20. ate collisions on a port Since all traffic on that VLAN is forwarded incorrectly out of the incorrect port there is a loss of connectivity This errdisable state can appear as a result of a duplex mismatch or faulty NIC CSCdm8s0035 When a Gigabit connection is reset registered on a Catalyst 6000 or 6500 the customers only 2 connection can potentially not reconnect A symptom of this issue can be that a Gigabit NIC does not connect after reset or disconnect CSCdm88013 2 Occasionally host NICs connected registered to WS X6248 TEL or customers only WS X6248 RJ 45 modules can incorrectly revert to half duplex after an autonegotiation failure For detailed information on Cisco bug IDs refer to the Bug Toolkit registered customers only Refer to Cisco Catalyst 6500 Series Switches Release Notes for more Catalyst 6000 and 6500 documented bug fixes Catalyst 5000 and 5500 Switches This table lists several known issues found on the Catalyst 5000 and 5500 switches Table 8 Directly connected hosts PCs routers and servers can indicate a connected state in the output of a show port command but do not forward Xmit Broadcast frames This causes connectivity issues that are only fixed when you issue the set port disable mod port and the set port enable mod port commands Ports on WS X5225R WS X5234 and WS X5201R modules CSCdr50629 7 do not transmit unicast registered customers
21. e Catalyst 5000 and 5500 switches For more details refer to Cisco bug ID CSCdk87853 7 registered customers only Upgrade to the latest drivers from Dell Contact Dell technical support and Cisco Technical Support for more details IBM 10 100 EtherJet CardBus Adapter IBM ThinClient Workstations Intel Pro 100 Intel Pro 1000 T Gigabit Copper NIC fails The motherboards were manufactured with an Intel Chipset that are incompatible with Cisco switches and Netgear hubs Extremely slow performance when operating at 10 Mbps Link flaps continuously after extended operation Consistent link up down connections to Catalyst switches When an Intel Pro 1000 T NIC is connected to a Catalyst switch you Certain 10 100 switches implement automatic correction for polarity reversed cables that are not completely compatible with the same correction provided by the IBM 10 100 EtherJet CardBus Adapter If the network speed is forced to 10 Mbps severe throughput problems can be experienced Workstations earlier than Service Pack 3 0 bounce the link on the switch after continuous use when attached to Catalyst 2948G or 4000 switches on software version 6 x and later May be caused by power management Contact Intel technical support for further information The interoperability issue arises from the implementation of Carrier Extension In order to resolve this problem a ne
22. ems Only disable autonegotiation to end devices such as older Gigabit NICs that do not support Gigabit autonegotiation Do not disable autonegotiation between switches unless absolutely required as physical layer problems can go undetected and result in spanning tree loops Rather than disable autonegotiation you can contact the vendor for a software or hardware upgrade for IEEE 802 3z Gigabit autonegotiation support Table 6Gigabit Autonegotiation Configuration Table Autonegotiation Setting ace sannzon Aene monseonat Gigabit Link Waa ave ink N Enabled fenas up du Disabled pisabiea lup up Enabled loga rom tp Disabled J gsabtea lup pown Issue these commands for Gigabit autonegotiation configuration e CatOS command set port negotiation mod port enable disable e Cisco IOS Software command negotiation auto no negotiation auto Verifying GBIC When you troubleshoot link issues on Gigabit Ethernet it is also important to verify the use of the correct Gigabit Interface Converter GBIC adapter with the correct cable distance Refer to Gigabit Interface Converter Installation Note for information on distances and cable specifications required for different versions of GBIC adapters Cisco Catalyst Switch Compatibility and Operation Specific Issues These sections deal with specific Cisco Catalyst switch issues that can affect performance compatibility and interoperation of certain NI
23. ernet MTU 1518 bytes are generated These packets are noted as giants on Catalyst switches Network connectivity is dropped every 2 gt minutes or the network card must be reinitialized several times to gain network connectivity Slow performance The link flaps when it connects to a Dell Optiplex GX200 PC Intel Pro 10 100 The NIC works properly when the PC is turned off but when it is turned back on the flap occurs When connecting to the Catalyst 2950 switch with an autonegotiation link it continuously flaps and the autonegotiation link Novell 5 0 issues A 3C905C or 3C920 integrated NIC on Dell Dimension XPS can experience network connectivity issues when Windows 2000 is run due to a power management issue Autonegotiation can fail to Catalyst 5000 and 5500 switches For more details refer to Cisco bug ID CSCdz60677 registered customers only Manufactured between May 21 and August 1 2001 1 0 33921641 2241835 Refer to 3Com technical support reference 1 0 16744826 2027011 Refer to 3Com technical support reference 2 0 4428387 2305072 Contact 3Com technical support Disable all power management functions Contact Dell for details on how to disable power management or for more details about this issue For more documentation refer to 3Com technical support reference 2 0 47464140 2853794 This problem is resolved in software release 4 5 1 and later for th
24. ex configuration Table 1 summarizes all possible settings of speed and duplex for FastEthernet NICs and switch ports Note This section is only applicable for 10 100 1000 Mbps LOOOBASE T NICs and not 1000BASE X NICs Table 1Autonegotiation Valid Configuration Configuration NIC Speed Duplex Configuration Resulting NIC Resulting PAN Speed Duplex Speed Duplex Assuming maximum capability of Catalyst switch and NIC is 1000 Mbps full duplex 1000 Mbps 1000 Mbps eee Full duplex _ Full duplex Link is established but the switch does not see any autonegotiation information from NIC Since Catalyst switches support only full duplex operation with 1000 Mbps they default to full duplex and this happens only when operating at 1000 Mbps 1000 Mbps Full duplex 1000 Mbps 1000 Mbps Full duplex Full duplex Assuming maximum 1000 Mbps 1000 Mbps 1000 Mbps capability of Full duplex Full duplex Full duplex NIC is 1000 Mbps full duplex 1000 Mbps Full duplex it Mbps a Mbps sa Mbps Correct Manual Full duplex tee ak Full duplex due to speed mismatch AUTO 100 Mbps 100 Mbps 100 Mbps Duplex Full duplex Full duplex Half duplex Mismatch AUTO 100 Mbps 100 Mbps 100 Mbps Duplex Full duplex Half duplex Full duplex Mismatch 1 100 Mbps Full duplex 100 Mbps 100 Mbps 100 Mbps Full duplex Full duplex _ Full duplex est
25. her Commands to Fix Workstation Startup Connectivity Delays e Excessive data link errors cause ports on some Catalyst switches to go into an errdisabled state Recovering From errDisable Port State on the CatOS Platforms describes what the errdisable state is explains how to recover from it and provides two examples of recovery from this state Why Do Autonegotiation and Compatibility Issues Exist Autonegotiation issues can result from nonconforming implementation hardware incapabilities or software defects When NICs or vendor switches do not conform exactly to the IEEE specification 802 3u problems can result Hardware incompatibility and other issues can also exist as a result of vendor specific advanced features such as autopolarity or cable integrity which are not described in IEEE 802 3u for 10 100 Mbps autonegotiation Generally if both the NIC and the switch adhere to IEEE 802 3u autonegotiation specifications and all additional features are disabled autonegotiation must properly negotiate speed and duplex and no operational issues exist General Troubleshooting for 10 100 1000 Mbps NICs Autonegotiation Valid Configuration Table Speed determination issues can result in no connectivity However issues with autonegotiation of duplex generally do not result in link establishment issues Instead autonegotiation issues mainly result in performance related issues The most common problems with NIC issues deal with speed and dupl
26. hernet module WS X4418 is affected In some cases autonegotiation with some Sun NICs can result in a nonoptimal configuration such as 10 Mbps half duplex instead of DO Mbps duple On a Catalyst 4006 with a Supervisor Engine II switch ports in the same VLAN can lose connectivity with one another The loss of connectivity results in a VLAN that appears to be partitioned into several isolated segments A host can be able to ping one set of devices in its VLAN while it cannot ping another set of devices in the same VLAN This loss of connectivity is independent of the slot in which a linecard is installed that is the same set of ports on a given linecard are affected regardless of the slot in which the linecard is installed The workaround is to reset the switch Xmit Err counter increments on unconnected ports for unexplained reasons The bug also resolves an issue of high CPU utilization conditions that can be caused by unconnected ports that are configured as host ports CSCds89148 a 7 registered customers only For detailed information on Cisco bug IDs refer to the Bug Toolkit registered customers only Refer to Catalyst 4500 Series Release Notes for more Catalyst 2948G 2980G and 4000 documented bug fixes Catalyst 2950 and 3550 Switches This table lists several known issues found on the Catalyst 2950 and 3550 switches Table 10 Cisco Bug ID p edt T The Catalyst 3550
27. his is also an indication that the receive Rev Err buffer is full This counter must be zero unless there is excessive traffic through the switch In some switches the Out Lost counter has a direct correlation to the Rev Err UnderSize This is an indication of a bad frame generated by the connected device Single Collisions This is an indication of a half duplex configuration Multiple This is an indication of a half duplex Collisions configuration Collisions This is an indication of faulty hardware NIC cable or switch port or a duplex mismatch Excessive Collisions This is an indication of overutilization of the f switch port at half duplex or duplex mismatch Carrier P P P Sense This is an indication of faulty hardware NIC itis is an tadicabon of the result of collisions Runts duplex mismatch IEEE 802 1Q dotlq or an Inter Switch Link Protocol ISL configuration issue Giants This is an indication of faulty hardware dotlq or an ISL configuration issue rm jab ga oO Table 4Explanation of CatOS show mac Command Counters Counter Description Rcv Unicast This is an indication of the number of unicast packets received Rcv Multicast This is an indication of the number of multicast packets received Rcv Broadcast This is an indication of the number of broadcast packets received Xmit Unicast This is an indication of the number of unicast packets transmit
28. iation Works Autonegotiation uses a modified version of the link integrity test that is used for 10BASE T devices to negotiate speed and exchange other autonegotiation parameters The original 10BASE T link integrity test is referred to as Normal Link Pulse NLP The modified version of the link integrity test for 10 100 Mbps autonegotiation is referred to as FLP The 10BASE T devices expect a burst pulse every 16 8 milliseconds msec as part of the link integrity test FLP for 10 100 Mbps autonegotiation sends these bursts every 16 8 msec with the additional pulses every 62 5 7 microseconds The pulses within the burst sequence generate code words that are used for compatibility exchanges between link partners This process of FLP used in autonegotiation maintains backward compatibility with existing 1OBASE T connections with the pulse burst every 16 8 msec to comply with the link integrity test for normal 1OBASE T hardware If a device sends FLP and only receives NLP the hardware immediately ceases transmission of the FLP and enables the standard 1OBASE T hardware to continue 1OBASE T operation This table describes the possible programmable options of the control register for a FastEthernet interface These options determine how the FastEthernet interface functions when connected to a link partner The 0 in the Bits column refers to the programmable register address and the decimal number after the 0 refers to the bit
29. issues that deal with physical connectivity and data link errors can be related to NIC issues Prerequisites Requirements There are no specific requirements for this document Components Used This document is not restricted to specific software and hardware versions Conventions Refer to Cisco Technical Tips Conventions for more information on document conventions Background Information Purpose This document discusses how to troubleshoot these issues e Autonegotiation e Physical Connectivity e Port Errors Data Link Errors e Continuous Link Up Down Situations e Gigabit Port Configuration e Common Catalyst Switch Software Issues e Common NIC Issues and Resolutions When you troubleshoot NIC issues with Catalyst switches the first step is to verify that the issue is not related to a possible configuration issue with the Catalyst switch For useful information that pertains to common connectivity issues with the configuration of the Catalyst switch refer to these documents e This document addresses initial connectivity delays that occur when workstations connected to Catalyst switches are unable to log in to a network domain Microsoft Windows NT or Novell or are unable to obtain a Dynamic Host Configuration Protocol DHCP address due to the Catalyst switch configuration The first step in order to troubleshoot these scenarios is to confirm that the switch configuration is correct as shown in Using PortFast and Ot
30. mple for CatOS Catalyst 2948G 2980G 4000 5000 and 6000 that Run CatOS Software e show port modDport Switch gt enable show port 3 1 Port Name Status VLAN Level Duplex Speed Type 3 1 notconnect 1 normal half 100 100BaseFX MM Example for Cisco IOS Software on the Switch Catalyst 2900XL 3500XL 2948G L3 and 6000 that Run Cisco IOS Software e show interfaces type Switch show interfaces fastethernet 0 1 FastEthernet0 1 is down line protocol is down States other than connectedand line protocol is up indicate a physical connectivity issue Complete these steps in order to troubleshoot physical connectivity 1 Set speed and duplex of both the NIC and switch at 10 Mbps full duplex Is there physical connectivity If desirable repeat this step with the speed set to 100 Mbps full duplex To set speed and duplex manually is probably not be required in order to establish physical connectivity For possible known issues see the Cisco Catalyst Switch Compatibility and Operation Specific Issues and NIC Capability and Operation Issues sections of this document 2 Replace the cable with a known good Category 5 Category 5e or Category 6 10 100 1000 Mbps Ethernet cable 3 Attempt physical connectivity across multiple switch ports Verify that the problem is consistent across multiple switch ports Also try multiple switches and hubs if applicable 4 Replace the NIC in order to determine if the problem is consiste
31. nt with the same brand and model of NIC For possible known issues see the Cisco Catalyst Switch Compatibility and Operation Specific Issues and NIC Capability and Operation Issues sections of this document 5 Create a service request with Cisco Technical Support and the NIC vendor Verifying Switch Port Configuration The default configuration of the Catalyst switch ports can cause specific interoperability issues for NICs The symptoms of problems can include DHCP issues and the inability to perform a network login When you troubleshoot any NIC or switch port issue verify that the configuration of port channeling and trunking is off and that spanning tree PortFast is enabled Refer to Using PortFast and Other Commands to Fix Workstation Startup Connectivity Delays for more documentation with regard to this configuration change Maintaining Link Link Up Down Situations Under certain circumstances interoperability issues between Cisco switches and various NICs can result in continuous or intermittent link up down situations These link up down situations are usually a result of power management features or jitter tolerance issues associated with the NIC e For link up down situations for CatOS these messages appear and are normal for link up down situations PAGP 5 PORTTOSPT Port dec dec joined bridge port dec chars PAGP 5 PORTFROMSPT Port dec dec left bridge port dec chars This is an example oe PAGP 5
32. ogin issues Notable slow performance when large files are received Problem only occurs with standard Microsoft NT 4 0 regardless of service pack Under normal conditions a Catalyst that reports numerous L2 physical errors on ports connected to 3C905C NIC adapters Refer to Cisco bug ID CSCdz32789 registered customers only Upgrade to driver version 4 01b or later which resolves DHCP issues Upgrade to driver 4 01b or later which resolves IPX autoframe type issues Alternatively manually configure Download latest driver from 3Com technical support Load latest driver and diagnostic tools available from 3Com Test performance back to back between two PCs and note errors on diagnostic tools Errors reported such as transmit under run and receive Over run cause physical layers to be reported by the switch and minor performance issues For more details refer to Cisco bug ID CSCat68700 registered customers only Upgrade to driver version 5 4 and in the advanced NIC properties set LnkChk to enable The Rel r fo 3Com technical rom 3 om f support refetence 3Com 3C985 3C985B 3Com 3C985 3C985B 3Com 3C905C or 3C920 integrated NIC on Dell Dimension XPS Compaq Netflex 3 Dell Optiplex GX200 Dell Precision 420 530 620 3C985 3C985B Clients are unable to log in or browse server but pings work correctly Packets larger than Eth
33. rk requests for a user selectable period of time Delays can be added ranging from 10 seconds In most cases if you add a delay in the t sdivextttha prob iesa a CBE CBE2 RBE ina port replicator or docking station with Windows 95 and have problems confirm that your laptop has the latest BIOS and that the latest manufacturer patches and utility software are installed Xircom XE2000 Westie NIC only Known limitation of PCMCIA NIC XE2000 NIC Refer to the XE2000 release notes autonegotiate to 100 autonegotiates to 100 Mbps full duplex Mbps half duplex Appendix A Information to Gather Before Creating a Service Request If the troubleshooting procedure outlined in this document does not resolve your issue you need to create a service request with Cisco Technical Support Before you create a service request gather this information p Identify the specific problem with NIC to switch interoperability For example is the problem only with DHCP Novell IPX login or performance 2 Issue the show tech support command from all affected Cisco devices if applicable or issue the show module show config show version or the show port commands 3 Know the make and model of the NIC Know the operating system and the NIC driver version 5 Verify the consistency of the problem P For example does the problem occur across multiple Catalyst switches Appendix B Understanding How Autonegot
34. s one percent to two percent of the total traffic See technical document TID1084 at Asant See technical document TID1109 at Asant support website See technical document TID1976 at Asant support website Turn off the energy saver mode in the control panel The network speed remains constant See technical document TID2095 at Asant support website See technical document TID2227 at Asant support website Upgrade to the latest NIC card driver and disable autopolarity Upgrade to the latest NIC driver and disable Bus Master These steps reduce FCS and alignment errors 3Com 3C905 3C905B 3Com 3C905 3C905B 3Com 3C905B 3Com 3C905C 3C905CX TX M 3Com 3C980 traffic Intermittent DHCP issues Unable to log in to Novell Internetwork Packet Exchange IPX network Slow performance when large files are received Layer 2 L2 errors reported on switch port FCS alignment CRC and runts and slow performance on high speed workstations The link fails to come up when the switch port is hardcoded to 100 Mbps full duplex or 100 Mbps half duplex and the NIC is set to autonegotiate Data corruption with Novell Despite the proper configuration of Catalyst switch ports workstations still experience some intermittent DHCP issues Despite the proper configuration of Catalyst switch ports workstations still experience intermittent Novell IPX l
35. t command and note the counter information Table 2Explanation of CatOS show port Command Counters Alignment errors are a count of the number of frames received that do not end with an even FCS error count is the number of frames that were transmitted or received with a bad checksum CRC value in the Ethernet frame These frames are dropped and not propagated onto other ports Xmit This is an indication that the internal transmit lance is full UnderSize These are frames that are smaller than 64 bytes which includes FCS and have a good FCS value Single SE Single collisions are the number of times the Collisions transmitting port had one collision before Multiple Collisions Multiple collisions are the number of times the transmitting port had more than one collision before Late A late allision occurs ghen two devices transmit Collisions at the same time and neither side of the connection detects a collision The reason for this occurrence is that the time to propagate the signal from one end of the network to another is longer than the time to put the entire packet on the network The two devices that cause the late collision never see that the other sends until after it puts the entire packet on the network Late collisions are detected by the transmitter after the first time slot of the 64 byte transmit time occurs They are only detected during transmissions of packets longer than 64 by
36. ted Xmit Multicast This is an indication of the number of multicast packets transmitted Xmit Broadcast This is an indication of the number of broadcast packets transmitted Delay Exceeded This is an indication of the number of frames discarded because of excessive delay in the switching process This is an indication that one of the devices on the port or segment transmits more than the allowed frame size MTU Exced Count of valid frames received which were discarded or filtered by the forwarding process In Discard Lrn Discard Packets which are forwarded and must not be forwarded In Lost Packets which can not be received because the input buffers are full Out Lost Packets which can not be transmitted because the output buffers are full 2 In Discard and Lrn Discard do not exist on all Catalyst platforms Table 5Possible Causes for Incrementing CatOS Counters Counter See s Delay Exced Severe problem with the switch Create a service request with Cisco Technical Support Verify ISL and dotlq configurations Verify MTU Exced another switch or router does not inject frame over maximum transmission unit MTU into the switch network Increments when the switch receives traffic on a Lrn Discard trunk for a specific VLAN while the switch does 2 not have any other ports on that VLAN Counter also increments when the destination address of the packet is learned on the
37. tes Its detection is exactly the same as it is for anormal collision it just happens later than it does for a normal collision Excessive Excessive collisions are the number of frames that are ie ae after 16 attempts to send the packet cane Carrier sense occurs every time an Ethernet Sense controller wants to send data and the counter is Runts These are frames sinaller than 64 bytes with a bad FCS value Giants These are frames that are greater than 1518 bytes and have a bad FCS value Table 3Possible Causes for Incrementing CatOS Counters These are the result of collisions at half duplex duplex mismatch bad hardware NIC cable or port or a connected device that generates frames that do not end with on an octet and have a bad FCS These are the result of collisions at half duplex FCS duplex mismatch bad hardware NIC cable or port or a connected device that generates frames with bad FCS This is an indication of excessive input rates of traffic This is also an indication that the transmit buffer is full The counter must only increment in situations in which the switch is unable to forward out the port at a desired rate Situations such as excessive collisions and 10 Mb ports cause the transmit buffer to become full If you increase speed and move the link partner to full duplex it minimizes this occurrence Collisions Xmit Err This is an indication of excessive output rates of traffic T
38. tility Verify autonegotiation settings Asant Fast 10 100 PCI Adapter Asant Fast 10 100 PCI Adapter Asant Fast 10 100 PCI Adapter Asant GigaNIC 1064SX PCI Card Macintosh Asant GigaNIC 1064SX PCI Card Macintosh 3Com 3C574 575 PCMCIA 10 100 3Com 3C595 Slow login or fails to log in to server Numerous CRC and FCS errors reported on switch when connected to Power Macintosh 9500 Slow network throughput after Macintosh OS 8 5 or 8 6 upgrade Network performance fluctuates Slow performance with AppleShare IP servers and PCI Ethernet cards Extremely slow performance when operating at 10 MB FCS or alignment errors recorded on the switch Noted slower performance When the 3C595 adapter is used in 100 MB half duplex This problem usually only represents one percent to two percent of the total When the energy saver mode is active under OS 8 6 the network speed becomes quite slow as soon as the monitor goes dim Customers report AppleShare IP servers slow down and eventually crash over time This occurs with both built in Ethernet and various PCI cards The 3C574 3C575 experiences slow performance when connecting at 10 MB with Catalyst 2948G 2980G 4000 5000 and 6000 switches This issue is caused by the NIC doing autopolarity upon linkup FCS or alignment errors when the 3C595 adapter is used in 100 MB half duplex This problem usually represent
39. w Auto Polarity keyword is added in the adapter advanced properties If needed the default setting of ON which means that the card compensates for reversed cables can be set to OFF polarity correction This restores normal throughput Upgrade IBM ThinClient to Service Pack 3 0 1 Choose Control Panel gt System gt Hardware gt Device Manager Choose Network Adapters gt Intel Pro 100 At the Power Management tab uncheck Allow the computer to turn off this device Contact Intel technical support for the latest driver can see poor network connections or excessive numbers of dropped packets The interoperability issue arises when a module with a ten bit interface TBI transmits an odd byte packet to a receiver with a Gigabit media independent interface GMI Sun Microsystems QFE Card Unable to manually set speed and duplex correctly Sun Microsystems v1 1 Gigabit Cards Unable to establish link Xircom CreditCard Ethernet 10 100 CE3B 100 Not negotiating or operating correctly at 100 Mbps full duplex Xircom CreditCard Not negotiating 10 Ethernet 10 100 Mbps full duplex CE3B 100 Carrier Extension is detailed in subsection 35 2 3 5 in the IEEE 802 3 specification Carrier Extension can be used to pad the last byte of a packet so the packet is aligned on an even numbered boundary Manually setting speed and duplex only affects the first of
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