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Release Notes for the Cisco 10000 ESR for Cisco IOS Release 12.0(11)SL

Table Of Contents

Release Notes for the Cisco 10000 ESR for Cisco IOS Release 12.0(11)SL


Upgrading to a New Software Release

System Requirements

Cisco 10000 ESR Software Features

Limitations and Restrictions

ChOC-12 and OC-12 ATM Line Card Support

Automatic Protection Switching Support

Important Notes


Channelized OC-12 Line Card Caveats

OC-12 ATM Line Card Caveats

Resolved Problems

Resolved in Cisco IOS Release 12.0(11)SL

Unreproducible Caveats

Obtaining Documentation

World Wide Web

Documentation CD-ROM

Ordering Documentation

Obtaining Technical Assistance

Cisco Connection Online

Technical Assistance Center

Documentation Feedback

Release Notes for the Cisco 10000 ESR for Cisco IOS Release 12.0(11)SL

November 13, 2000

These release notes provide information about Cisco IOS Release 12.0(11)SL, which runs on the Cisco 10000 Edge Services Router (ESR).

These release notes are updated as needed to describe new features, memory requirements, hardware support, software platform deferrals, and changes to the microcode and related documents.

Cisco IOS Release 12.0(11)SL is based on Cisco IOS Release 12.0(11)S4. For a list of the software caveats that apply to Cisco IOS Release 12.0(11)SL, see the "Caveats" section and the release notes for Cisco IOS Release 12.0(S). To review the release notes for Cisco IOS Release 12.0S, go to and click Technical Documents > Cisco Product Documentation > Cisco IOS Software Configuration > Cisco IOS Release 12.0 > Release Notes > Cisco 12000 Series Router > Cisco 7000 Family and 12000 Series - Release Notes for Release 12.0(S).

Use these release notes in conjunction with the cross-platform Release Notes for Cisco IOS Release 12.0.


Upgrading to a New Software Release

System Requirements

Cisco 10000 ESR Software Features

Limitations and Restrictions

Important Notes


Resolved Problems

Obtaining Documentation

Obtaining Technical Assistance

Upgrading to a New Software Release

For specific information about upgrading your Cisco 10000 ESR to a new software release, see the Cisco 10000 ESR Software Configuration Guide.

For general information about upgrading to a new software release, see the product bulletin Cisco IOS Upgrade Ordering Instructions located at:

For additional information about ordering Cisco IOS software, refer to the Cisco IOS Software Releases URL:

System Requirements

We recommend that you use 512 MB of memory on the Performance Routing Engine (PRE). New PREs are shipped with 512 MB of memory. In a redundant setup, both PREs should have the same amount of memory.

Cisco 10000 ESR Software Features

The following features are supported in the Cisco 10000 ESR.

Table 1 Principal Software Features 


Cisco Discovery Protocol (CDP)

Simple Network Management Protocol (SNMP)


SONET 1+1 Automatic Protection Switching (APS)



High-Level Data Link Control (HDLC)

Frame Relay

Point-to-Point (PPP)

Multilink Point-to-Point (MLP)

Multiprotocol Label Switching

Multiprotocol Label Switching (MPLS) edge services

Multicast Features

Multicast Static Routes

Multicast Routing Monitor (MRM)

Multicast Services

Internet Group Management Protocol (IGMP)

Protocol-Independent Multicast (PIM)

Distance Vector Multicast Routing Protocol (DVMRP)

Cisco Group Management Protocol (CGMP)

Unidirectional Link Routing (UDLR)

Session Directory Protocol (SDP)

Multicast Source Discovery Protocol (MSDP)

Border Gateway Protocol (BGP)

Quality of Service

Committed Access Rate (CAR)

Weighted Random Early Detection (WRED)

QoS Policy Propagation on BGP (QPPB)

Marking packets by using IP header precedence and differentiated service code point (DSCP)

Routing Protocols

Border Gateway Protocol (BGP)

Intermediate System-to-Intermediate System (IS-IS)

Open Shortest Path First (OSPF)

Interior Gateway Routing Protocol (IGRP)

Enhanced Interior Gateway Routing Protocol (EIGRP)

Routing Information Protocol (RIP)

Security Features

Standard and extended access lists

Authentication, Authorization, and Accounting (AAA)

Kerberos authentication and client support on Telnet

Radius authentication

Terminal Access Controller Access Control System Plus (TACACS+)

Limitations and Restrictions

This section describes important limitations and restrictions that you should review before you use the Cisco 10000 ESR.

ChOC-12 and OC-12 ATM Line Card Support

Software support is available for the Channelized OC-12 (ChOC-12) line card and the OC-12 ATM line card.

Be sure to review the caveats described in the "Channelized OC-12 Line Card Caveats" section and the "OC-12 ATM Line Card Caveats" section.

Automatic Protection Switching Support

Automatic protection switching is supported on the OC-12 POS line card, with the following limitation.

For APS to work properly, you must always have an OC-12 POS line card installed in the lower-numbered (odd) slot.

The system receives clocking information from the line card in the odd slot. If you remove the odd-numbered card (or if the clocking mechanism on that card fails), the clocking is lost and the data path is shut down. (Caveat no. CSCdr81416)

To manage this APS behavior, we recommend the following:

1. For the card pair, fully configure the lower-numbered card, and leave the higher-numbered card set to its default configuration.

2. Before you remove a card from the odd slot, run the no associate command and shut down the card. The following is an example of disabling APS for cards in slots 5 and 6:

Router(config)# redundancy
Router(config-r)# no associate 5 6
Router(config-r-a-sl)# exit
Router(config)# interface pos 5/0/0
Router(config-if)# shutdown

You can now remove the card in slot 5.

3. Move the card located in the even slot to the odd slot and enter the no shutdown command. Traffic flow resumes. Insert a new card into the even slot and reconfigure the pair for redundancy.

Important Notes

You can run up to 2000 Frame Relay sessions or 1300 PPP sessions, and you can configure up to 300 BGP peers on the Cisco 10000 ESR. The router also supports up to 512 Multilink Point-to-Point (MLP) protocol sessions.

Note Each T1 interface in an MLP bundle represents a single PPP session. Thus, if you configure 130 MLP bundles of 10 T1 interfaces, each results in 1300 PPP sessions (which is the maximum number of PPP sessions that are supported on the Cisco 10000 ESR).


This section describes the caveats for the Cisco 10000 ESR running under Cisco IOS software Release 12.0(11)SL. Additional caveats can be found in the "Channelized OC-12 Line Card Caveats" section and the "OC-12 ATM Line Card Caveats" section.


If you preconfigure a line card using the card command, this significantly degrades PRE performance.

Workaround: Do not use the card command to preconfigure line cards. Instead, use the no card command to remove references to cards that are not in the chassis.


The router sends out DHCP INFORM and DISCOVER messages containing an incorrect Ethernet address.

Workaround: No workaround is necessary. This caveat is harmless because these DHCP messages are not used to acquire IP addresses. They are used to gather environmental data such as the domain name server address.


When you use the Frame Relay autosense feature, the Cisco 10000 ESR sends all three LMI status message types immediately after the interface starts responding. However, sometimes the switch at the other end is not ready to receive messages and as a result, misses one or two messages that were sent. LMI autosense waits until the next scheduled interval (default is 1 minute) to send the messages again.

This problem primarily affects clear channel CT3 interfaces.

Workaround: There is currently no workaround.


When you send large numbers of packets from the Gigabit Ethernet line card to the PRE in the Cisco 10000 ESR, you may lose a small number of packets. This only occurs for some packet sizes at very high bandwidths, with loss rates of a few parts per million.

Workaround: There is currently no workaround.


During periods of heavy traffic (approaching interface line rate), some interfaces may experience inconsistent performance between interfaces of the same type.

Workaround: There is currently no workaround.


You cannot generate FDL Bellcore remote loopback requests.

The Bellcore keyword in the t1 <t1-number> loopback remote line fdl bellcore command is not supported. Bellcore (Telcordia) began phasing out their standard in favor of the ANSI standard in the early 1990s.

The software responds to FDL Bellcore remote loopback requests, but does not generate these requests.

Workaround: Use the t1 <t1-number> loopback remote line fdl ansi command to run a remote loopback.

CSCdr52081 and CSCdj94209

The PRE may crash if you repeatedly change a port back and forth from channelized to unchannelized.

Repeated conversions of a T3 port from channelized mode to unchannelized mode and back, with intervening assignments of IP addresses to the interfaces and ping testing, may cause the PRE crash.

Workaround: Reload the chassis.


If you remove a line card during periods of heavy traffic and then reinsert it (or another line card of the same type), on rare occasion the card fails to pass traffic.

Workaround: Use the shutdown command to shut down interfaces and controllers before you remove the line card. If a failure occurs, you can activate the card by entering the privileged EXEC mode microcode reload pxf command.


If large MLP configurations are in use, and you attempt to copy the configuration from a TFTP server directly into the running config, the copy may fail. Failures may include interfaces not appearing or IPCP or LCP states not opening correctly.

Workaround: These failures are far less likely to occur if the configuration is copied to bootflash, and then from bootflash to the running config. Copy the configuration file to the startup config and then reload the router.


Limited support for APS. For detailed information, refer to the "Automatic Protection Switching Support" section.

CSCdr92058 and CSCdr98370

Large multicast groups may cause CPU hog issues in the PIM process. The tested number of 500 destinations in one group caused CPU hog messages (max limit is unknown).

Workaround: There is currently no workaround.


Packet throughput may be less than optimal on all interfaces when a large number of MLP bundles are configured or during periods of heavy MLP traffic.

Workaround: Limit the number of MLP bundles you configure.


The Flash disk can fall into the chassis when you insert the disk into the empty space to the right of the slot B in the PRE flash assembly.

Workaround: Pay extra attention when inserting a flash disk into the PRE flash assembly. Do not insert the disk in the empty space to the right of the slot B—if you insert a card in that space, it will fall into the chassis.


If you send a large number of small packets in large multicast groups, this may cause the following debug messages to appear on the console:

../src-4k-c10k/c10k_isr_ct3.c, line 548
 <idb invalid on vc 0x624FA974, slot 12 port 0 chan 104
 dh 05E0001F 680100FF>
 60044EB4 60016E48 60017238 601F2C9C 601D0404

../src-4k-c10k/c10k_isr_ct3.c, line 535
 <port 7 invalid>
 60044CEC 60016E48 60017238 601F2C9C 601D0404

Workaround: Decrease the number of small packets.


When older CT3 line cards are powered on with live DS3 signals present at the receive BNC connector, the receive line interface device on the board may lock up, preventing the controller from running. You can verify this symptom by using the show controller t3 command, which shows that the controller is down, the Receiver has Loss of Frame, and the Line Code Violations counter is counting errors at a rapid rate.

Workaround: Replace the CT3 line card with an upgraded line card. CT3 line cards with Version 800-05547-04 Revision A0 or later have a hardware design change to avoid this problem. On older cards, you can work around the problem by removing the receive signal momentarily after the line card is powered on. For example, remove and reinsert the coaxial cable on the associated RX BNC connector on the rear of the chassis.


When a Cisco 10000 is reloaded with a large number interfaces configured as Frame Relay DCE, line cards may report down and up again before the chassis stabilizes.

Workaround: Wait for couple of minutes until the chassis stabilizes.


The default logging parameter (logging rate-limit console all 10 except critical) sets console logging to disabled.

Workaround: Enter the logging console critical command to view the most important events such as card up/down and toaster failure events.


If you are running more than 1300 PPP sessions on a Cisco 10000, some of those sessions may not come up after you reload the Cisco 10000. In the show interface command display, those sessions may appear in an LCP closed state or an IPCP closed state.

Workaround: Shut/no shut the underlying interface.


If you enter the clear ip mroute command on a system with large multicast groups, CPU hog issues may arise that cause problems of moderate severity (such as losing keepalives).

Workaround: Do not use the clear ip mroute command in large multicast groups.


If you reload a Cisco 10000, some initialization messages are logged to the console before the startup-config is loaded. These initialization messages are transitional and may report an incorrect state, especially for the FastEthernet interface.

00:00:15: Downloading Microcode: file=system:pxf/ucode_file, 
version=2.0(21.4), description=Nightly Build Software created Wed 
13-Sep-00 00:38
00:00:21: %LINK-3-UPDOWN: Interface Ethernet0/0/0, changed state to up
00:00:21: %LINK-5-CHANGED: Interface FastEthernet0/0/0, changed state to 
00:00:23: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0/0/0, 
changed state to up
 0:00:23: %LINEPROTO-5-UPDOWN: Line protocol on Interface 
FastEthernet0/0/0, changed state to down

These messages are not displayed in the buffered log.

Workaround: Ignore these messages.


Under heavy load on the Cisco 10000, serial line keepalives may be dropped, which causes serial lines to go down and then recover.

Workaround: There is currently no workaround.


When you boot the Cisco 10000, the system may display the following messages:

*Oct 17 12:32:48.287: %SNMP-3-TRAPBLOCK: Attempt to generate SNMP trap 
from a process with blocking disabled
 -Traceback= 60565064 606A6B34 60678238 60678438 6067AD88 6067AF30 
602FCBDC 6024817C 60248168

Workaround: Ignore the messages.


If you run the show interface command on interfaces with HDLC encapsulation, the input bytes statistics do not update properly. The input bytes display (or polling the mib value if InOctets) reports a very large (a negative value) number.

Workaround: There is currently no workaround.


If incoming multicast packets match an input access list that has the log option enabled, the output of the show log command and show access-list commands display double the number of matches.

Workaround: There is currently no workaround.


If the PRE microcode is reloaded because of an unusual condition (such as a system crash), multiple pxf_crashinfo files are produced within a 1 or 2 seconds of each other.

Workaround: There is currently no workaround.


If you perform an SNMP walk or view entries in the if table, cef-layer internal interfaces appear in the interface table.

Workaround: Ignore interfaces whose descriptor contains the string .0-cef layer.


Inverse ARP requests are sometimes generated for only 5 of 10 configured PVCs.

Workaround: There is currently no workaround.


A large number of BGP networks can cause 100% CPU utilization on the PRE. If this occurs, the line cards may reload.

Workaround: There is currently no workaround.


The CLI help text for the access-list command does not show the A.B.C.D option for the source address. For example:

 Router(config)#access-list 1 ?
   deny    Specify packets to reject
   permit  Specify packets to forward

Workaround: Disregard the help text and, enter the complete access-list command as you normally do. For example:

 Router(config)#access-list 1 permit log


If you copy a large set of reconfiguration instructions to a large configuration using TFTP, the Cisco 10000 can crash. For example, if the configuration instructs the system to run the no channelized command on each T3 controller, the router may crash.

Workaround: Either limit the number of reconfiguration instructions, or reload the router with a blank configuration before you copy config information into the running config.


When you change the configuration of the two PRE slots from redundant to nonredundant, TBB_LENGTH_ERRORs appear and the PXF reloads.

 #config t
 (config-r)#no associate slot 1 2
 <now TBB_LENGTH_ERROR message appear, and toaster reload>

This problem occurs if you first boot the system without APS, then configure APS, then deconfigure APS while there is active traffic on the redundant slot.

Workaround: Boot the system with APS configured before deconfiguring it, or turn off all traffic, keepalives, and CDP packets on the secondary slot before deconfiguring APS.


On rare occasions, a hardware timing problem may cause a PRE fault.

If this error occurs, the event below is logged in SysLog as follows:


Workaround: There is no workaround for this problem. The PXF is restarted by Cisco IOS and normal communications should resume.

Channelized OC-12 Line Card Caveats

This section describes the caveats for the Cisco 10000 ESR ChOC-12 line card.


If you configure a DS3 BERT pattern 2^20-O153 on any unchannelized DS3 (by using the bert pattern 2^20-O153 interval 1-14400 command), and you then connect the line card to T-Bird 310 test set, the pattern does not synchronize with T-Berd 310.

Workaround: Use a different BERT pattern.


When you enter the hw-module slot_number reset command, the event sequence is displayed in a different order than that shown by the reload command if the logging console is configured to informational.

Workaround: There is currently no workaround. You only encounter this problem if you change the default logging (critical) to informational.


If you configure an STS-1 on a ChOC-12 line card as unchannelized and then configure the remote side to send idle-character marks (namely, 0xFF), the T3 line stops responding and transmits a Remote Alarm Indication (RAI).

Workaround: When you use unchannelized T3 mode, configure the remote side to send idle-character flags (0x7E). To set this value, use the interface configuration mode idle-character command.


On rare occasions, the system may not be able to retrieve remote performance data if you are using a ChOC-12 line card that has its T1s configured with ANSI FDL enabled.

Workaround: There is currently no workaround.


When the encapsulation mode is changed from PPP to HDLC or vice-versa, the system drops about 3 of the next 10 packets transmitted. After that, the packets are transmitted normally.

Workaround: There is currently no workaround.


When a ChOC-12 line card is reconfigured from a channelized T3 configuration to an unchannelized T3 configuration or vice-versa, the initial packets are not forwarded.

Workaround: Save the configuration and then remove and reinsert the ChOC-12 line card. When the card restarts, it does not drop the initial packets.


The T1 framer associated with a T1 that was removed continues to send out a valid frame, even though the T1 no longer exists. This prevents the remote side from knowing that the T1 is no longer there (since it is getting a valid frame).

Workaround: There is currently no workaround.


Occasionally an alarm LED comes up as active even though no alarms are indicated after entering the show controller command.

Workaround: Perform a shut/no shut configuration on the SONET controller. For example:

conf t
controller sonet 7/0/0
no shut


The ChOC-12 serial interface may receive pings at a very slow rate. On average, the receiving interface only increments at approximately 10 to 15 packets-per-second during a sweeping ping. In addition to sweeping pings, this problem occurs if you send other types of pings (for example, 1000 pings, 1000 bytes in size).

Workaround: There is currently no workaround.


Kentrox DS3 subrate mode does not work when you set it to full bandwidth (45.2 Mbps on Kentrox CSU, 44210 Kbps on a Cisco10000 ESR).

Workaround: Set the subrate mode on the ChOC-12 board to Digital Link mode, bandwidth = 44210. This fix works with and without scrambling.


The router crashes if you load multiple configurations (greater than 5) and if you clear large configurations (for example, 336 T1s, each on two ChOC-12 cards).

Workaround: Reload the router before you reload a large configuration file.

OC-12 ATM Line Card Caveats

This section describes the caveats for the Cisco 10000 ESR OC-12 ATM line card.


To use the loopback diagnostic path command, you need a loopback connector, or the loopback continuously cycles through the framer interrupt handler.

Workaround: Ensure that there is a loopback connector in place before you enable a diagnostic path loopback.


Under normal (IMIX) traffic loads, the OC-12 ATM line card segmenter may not keep up with line rate. This is indicated by an increase in "output queue drops" or "output buffer failure" counts as displayed by the show interface command.

Workaround: There is currently no workaround.


When an access list is applied to the main interface of an ATM card that contains PVCs on subinterfaces, the access list does not apply to the subinterfaces. It is correctly expected that any access list applied to a main interface should affect the subinterfaces as long as they do not have access lists of their own.

Workaround: If an access list needs to affect the subinterface, place it directly on the subinterface.


Sometimes, the show interface command output for the packets input and bytes input counters displays erroneous values of 4 trillion plus.

Workaround: There is currently no workaround.


In certain situations, the interface stops responding when a PVP is deleted. This occurs when the only VCs on the ATM interface are the two F4 OAM VCs associated with a PVP, and those VCs are in a down state. If the PVP is deleted at this point, the line protocol for the interface stops responding briefly and then returns to an up state.

Workaround: If this momentary change in line protocol state is causing undesirable effects, make sure an additional VC is created on the interface before you delete the PVP.


Under rare circumstances, closure of VBR-nrt VCs fail, leaving the associated VPI/VCI value unavailable for future use. This can occur for VCs with relatively small rates (such as PCR and SCR values under 1500 kbps) that are actively passing traffic at the time the VC is being closed. The symptoms are an IOS error message alerting the user to an Open_Channel failure with a status of 4 and an associated PVC that transitions to the inactive state.

Workaround: Ensure that all traffic is stopped on a PVC before modification or deletion. If this situation is encountered, use the hw-module slot slot_number reset command to reload the line card.


Under somewhat loaded conditions, in which a large number of VCs are configured and receiving traffic simultaneously, and many end-of-packet cells line up (arrive at the reassembler at the same time), the reassembler is unable to keep up and applies back-pressure on the framer. This back-pressure can lead to framer input FIFO overflow that results in incomplete packets being presented to the reassembler. These incomplete packets are dropped by the reassembler and counted as input errors.

Workaround: There is currently no workaround.


Under conditions where the OC-12 ATM line card is reloaded while traffic is actively passing over multiple VCs, some or all of the VCs may not successfully reopen after the line card is reloaded.

This is indicated by one or more of the following error messages:

%C10K-4-LC_WARN:Slot[2/0] 1oc12atm-1 SAR:0/100 no Open_Channel ack
        returned for reassembly device (handle 0x0001)

%C10K-4-LC_WARN:Slot[2/0] 1oc12atm-1 SAR:0/100 Open_Channel failure for
        reassembly device (handle 0x0001), status 2

Workaround: Reload the line card firmware by using the hw-module slot slot_number reset command. If the problem persists, stop the traffic and reload the line card firmware.


For VBR-nrt VCs with low SCR values (400 kbps and below), a steady stream of small packets (for example, 64 byte packets) only achieves roughly 85% of the requested SCR.

Workaround: There is currently no workaround for this problem.


Mass configuration (which occurs during boot/reload and can occur during link state changes) takes a long period of time (for example, over 40 minutes for 2000 VCs associated with a main interface) with large numbers of PVCs (100s to 1000s). This problem occurs when attempting to configure large numbers of PVCs on the main interface (or multipoint subinterfaces) with static maps on each PVC.

Workaround: Do not configure more than 500 PVCs on a single OC-12 ATM line card or more than 900 PVCs on a Cisco 10000 ESR.


If you associate a VC-class containing an unsupported traffic class (for example, UBR+ traffic class) with a PVC on an OC-12 ATM line card, this results in multiple error messages.


router(config)#vc-class atm class1
router(config-vc-class)#ubr+ 10000 1000
router(config)#int atm3/0/0
router(config-if)#pvc 0/200
router(config-if-atm-vc)#class-vc class1 
UBR + not supported on interface ATM3/0/0
UBR + not supported on interface ATM3/0/0
UBR + not supported on interface ATM3/0/0

Workaround: Do not associate VC-classes that contain unsupported traffic classes to OC-12 ATM line cards.


MPLS over a Cisco 10000 ESR OC-12 ATM line card sub-interface (running either OSPF or ISIS) fails when directly connected to an OC-12 ATM interface on a GSR router if the default MTU values remain unchanged.

The default MTU for the Cisco 10000 ESR OC-12 ATM line card is 9180, while the default MTU for the GSR OC-12 ATM line card is 4470.

Workaround: Reconfigure the MTU value on either the Cisco 10000 ESR OC-12 ATM line card or the GSR OC12 ATM line card to match the other end.


Under normal (IMIX) traffic loads, the OC-12 ATM line card reassembler may inappropriately drop packets, yielding less than line rate.

This is indicated by an increase in "input error" and "abort" counts in the show interface display for the line card in question.

Workaround: There is currently no workaround.


If you reload PXF while traffic is being sent, this brings down the IPC connection. This problem occurs when microcode is reloaded while sending traffic through hundreds of PVCs.

Workaround: If you want to reload the microcode, stop sending traffic and then reload the microcode.


With multiple PVP tunnels, if the aggregate traffic received by one or more of the PVPs is heavily oversubscribed (starting at about 110% of the tunnel's PCR rate), the traffic on companion PVP tunnels on that interface may experience throughput that is lower than expected.

Workaround: There is currently no workaround.


If multiple VBR and UBR VCs are configured together and traffic is flowing over both types of VCs, throughput on the VBR VCs may suffer (i.e., may fall noticeably below the associated Sustainable Cell Rate [SCR]) while UBR traffic appears unaffected.

Workaround: There is currently no workaround.


On rare occasions, the OC-12 ATM line card segmenter fails to respond to requests for statistics. This is indicated by one or more of the following error messages:

%C10K-4-LC_WARN:Slot[2/0] 1oc12atm-1 SAR:no Get_Channel_Stats ack 
          returned for segmentation device, continuing

%C10K-4-LC_WARN:Slot[2/0] 1oc12atm-1 SAR:segmentation device 
         Get_Channel_Stats failure, status is 0x02, continuing

Workaround: Reload the line card firmware by using the hw-module slot slot_number reset command.


Under some conditions the OC-12 ATM line card reassembler may be unable to process all incoming packets and the reassembler may inaccurately count these erroneous packets as aborts. This may be indicated by an increase in the input "abort" counter in the show interface command display.

Workaround: There is currently no workaround for this problem.

Resolved Problems

This section lists resolved problems.

Resolved in Cisco IOS Release 12.0(11)SL

This section lists problems that are resolved in Cisco IOS Release 12.0(11)SL. For a list of problems that were resolved in previous Cisco IOS Releases, refer to the release notes for those particular versions.


The show controller t3 command does not display DSU information.


If the ChOC-12 line card is reloaded, the SONET controller on the line card may not respond.


The show hardware command lists preconfigured cards (cards that are not physically located in the chassis).


The ChOC-12 line card CLI (and the printed version of the Cisco 10000 ESR Software Configuration Guide) list several T1 BERT tests that are not supported on the ChOC-12 line card.


After you reload a router in a configuration that includes back-to-back CT3 connections using Frame Relay subinterfaces, the system may report that, for some interfaces, the interface is up but the line protocol is down.


If 2000 Frame Relay connections are configured between back-to-back Cisco 10000 routers, and if you restart one chassis, this causes line cards on the other chassis to report a down state before returning to an up state.


The output from the show controller sonet command always displays the STS Path Signal Label as 00.

CSCdr84791 and CSCdr98217

The Cisco 10000 ESR console may stop responding if you run two Cisco 10000 ESRs back-to-back with the following characteristics: approximately 350 T1 and sub-T1 lines between them and POS ports that bounce every 30 to 60 seconds.


In rare situations, the gigabit Ethernet port stops receiving packets, causing the input drop count to increment.


If you ping a multicast group of more than 200 interfaces or bring up such a node in a live network, this may cause CT3 line card protocols to stop responding.


T1 frames remain in loopback mode on the Channelized OC-12 line card.


Under rare conditions, it is possible to run a fully-booted IOS on both PRE modules at the same time. (At least one of the IOS images will be the "eboot" boothelper image.) In this situation, the console logs on both of the PREs may report that a duplicate address has been detected.


The Cisco 10000 ESR may crash with a watchdog timeout after it dumps several individual CPUHOG messages (if CPUHOG checking is active).


When the Cisco 10000 gigabit Ethernet line card receives giant frames of 17000 to 18000 bytes, the gigabit Ethernet line card reloads.


SNAP and SAP/IP packets received on the gigabit Ethernet interface are dropped when parallel express forwarding is enabled.


Pinging may fail when you attempt to ping through the ATM interface with a packet size that is greater than the MTU for the interface.


When two Cisco 10000s are connected back-to-back by CT3 links, if no CT3 framing is configured on either end of the link, the show controller t3 command may report incorrect framing types.


On system startup, some T1s in a T3 may not report as running. As a result, all interfaces on each affected T1 remain in a down state.


On rare occasion, when the local traffic load approaches maximum sustainable throughput while processing packets that are less than 512 bytes in length, the PRE may restart.


The show interface multilink command generates two traceback messages.


The aps ber threshold and the pos threshold commands modify both the interface threshold (which triggers the facility alarm on the PRE) and the APS threshold (which triggers line card APS cutovers).


On rare occasions, the host software loses management synchronization with the SAR firmware.


Copying a configuration with a large number of channel groups, in this case the maximum number of channels 768 with encapsulation PPP, ipc is disabled on that line card. This causes the protocol state of all serial interfaces to remain in the down state.


The hw-module slot <x> shutdown configuration command is ignored after IOS reloads even though it appears in the running configuration.


On a Cisco 10000 system with a channelized OC-12 line card where the card has been configured with one or more channel groups (nxDS0) we have observed that sometimes the channel in question stops forwarding inbound packets.


When this ucode crash and reload happens, once in a while the PPP state between RP and toaster are getting out of state giving rise to the SW exception.


This bug occurs when the Kentrox CSU/DSU and the C10000 CT3 card are both configured for full bandwidth DS3 (45.0Mbps on Kentrox, 44210Kbps on CT3). With this configuration the interface will not pass data.


Under rare situations, a DS1 channel will generate a stream of erroneous packets after the channel is configured. Normal traffic will not be able to be passed on this channel.


High volumes of traffic can lead to unnecessary packet drops on an OC-12 ATM line card.


Sometimes PPP does not negotiate. The end result is that the interface line and protocol say up, but PPP is stuck in a IPCP listen state.

Unreproducible Caveats

This section lists problems that were previously listed under Caveats in Cisco IOS Release 12.0(10)SL, but have not been reproduced during testing. In the unlikely event you experience the problems described in this section, contact Cisco customer service.

For a list of unreproducible caveats in previous Cisco IOS Releases, refer to the release notes for those particular versions.


In rare cases, after extended use, the system does not allow you to access the NVRAM. In these situations, the show start command returns a No such device message, and the cd nvram command returns a No memory available message.

Workaround: Free up memory by restarting the router.


Some combinations of config register settings, boot config flashdevice:filename settings, and redundancy configurations may cause the system to report that there is not enough space to save the startup configuration. In particular, the CONFIG_FILE variable, which in normal usage should follow the value of the boot config command, may take on a value unexpectedly.

Workaround: Use the no boot config command to remove the redirection of the startup configuration. As a safety measure, save a copy of the current configuration first.

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