Cisco IOS Release 12.0(23)SX4

These release notes provide information about Cisco IOS software Release 12.0(23)SX4 for the Cisco 10000 series Internet router. These release notes describe new features, memory requirements, hardware support, software platform deferrals, and changes to the microcode and related documents.

Cisco IOS Release 12.0(23)SX4 is based on previous 12.0(23)SX releases. Cisco IOS 12.0(23)SX releases include all of the new features introduced in Cisco IOS Release 12.0(23)S. You can review the release notes for Cisco IOS Release 12.0(23)S at the following URL:

Cisco Security Advisory

Cisco routers and switches that are running Cisco IOS software and that are configured to process Internet Protocol Version 4 (IPv4) packets are vulnerable to a Denial of Service (DoS) attack. A rare sequence of crafted IPv4 packets sent directly to the device might cause the input interface to stop processing traffic when the input queue is full. No authentication is required to process the inbound packet. Processing of IPv4 packets is enabled by default. Devices that are running only IP Version 6 (IPv6) are not affected.

Cisco has made software available, free of charge, to correct the problem. For more information, refer to the Cisco Security Advisory: Cisco IOS Interface Blocked by IPv4 Packet, located at the following URL:

System Requirements

This release requires that you have the performance routing engine (PRE, Part Number ESR-PRE1) installed in the Cisco 10000 series router chassis. To verify which PRE is installed in the router, use the show version command.

Memory Requirements

The following table lists memory requirements for the Cisco 10000 series router.

Upgrading to a New Software Release

Feature Set by Router	Image Name	Flash Memory	DRAM Memory	Runs From
Edge Services Router	c10k-p10-mz	40 MB	512 MB	RAM
Service Provider/ Secured Shell 3DES	c10k-k4p10-mz	40 MB	512 MB	RAM

For specific information about upgrading your Cisco 10000 series Internet router to a new software release, refer to the Cisco 10000 Series Router Quality of Service Configuration Guide located at the following URL:

For general information about how to upgrade to a new software release, refer to the product bulletin Cisco IOS Upgrade Ordering Instructions located at the following URL:

For information about how to order Cisco IOS software, refer to the Cisco IOS Software Releases located at the following URL:

Upgrading Software from Earlier Cisco IOS Releases

If you are upgrading your software from Cisco IOS Release 12.0(21)SX or Release 12.0(21)SX1 to Cisco IOS Release 12.0(23)SX4, you must upgrade the eboot image on the Cisco 10000 series router. If you fail to upgrade the eboot image, the router configuration may not load properly, and a checksum error appears on the console. If you are upgrading the software from an earlier Cisco IOS release, you do not need to upgrade the eboot image.

Upgrading from Cisco IOS Release 12.(14)SL or from Earlier 12.0(x)SL-based Releases

If you are upgrading your software from Cisco IOS Release 12.0(14)SL or from earlier 12.0(x)SL-based releases to Cisco IOS Release 12.0(23)SX4, save your current configuration file. If you decide to reinstall Release 12.0(14)SL or an earlier release, you must also reinstall the configuration file associated with that release. This is because some Border Gateway Protocol (BGP) configuration-file entries in Release 12.0(23)SX4 are not compatible with Release 12.0(14)SL or earlier releases.

Upgrading Software on Redundant PREs

When you upgrade software on redundant Cisco 10000 series router performance routing engines (PREs), be sure to download the software to both the active PRE and the standby PRE before you reload both PREs. For more information, refer to the installation guide for your specific PRE at the following URL:

New Features—Cisco IOS Release 12.0(23)SX4

Cisco IOS Release 12.0(23)SX4 includes all of the new features introduced in Release 12.0(23)SX, and all of the problems fixed in Release12.0(23)SX3, Release 12.0(23)SX2, and Release 12.0(23)SX1. For more information, refer to the appropriate Release Notes document located at the following URL:

New Features—Cisco IOS Release 12.0(23)SX

The following is a brief list of the new features and improvements in Cisco IOS Release 12.0(23)SX on which Cisco IOS Release 12.0(23)SX4 is based. For more information, refer to the Release Notes for the Cisco 10000 Series Internet Router for Cisco IOS Release 12.0(23)SX.

The multirouter-automatic protection switching (MR-APS) feature allows switchover of SONET connections in the event of circuit failure. MR-APS is often required when connecting SONET equipment to telco equipment. APS refers to the mechanism of using a "protect" SONET interface in the SONET network as the backup for a working SONET interface. When the working interface fails, the protect interface quickly assumes its traffic load. For more information on this feature, refer to the following URL. Note that the documentation includes aps commands for POS interfaces. However, the same commands also apply for ATM interfaces.

The Multicast for Multiprotocol Label-Switching (MPLS) Virtual Private Network (VPN) feature allows service providers to offer multicast services over their MPLS core network. Multicast for MPLS VPN allows end-user customers to improve productivity and communication flow for applications such as corporate communication, e-learning, data warehousing, content synchronization, trading stocks and commodities (stock quotes and ticker information), and emergency messaging services.

The DiffServer Aware Traffic Engineering feature extends DiffServe quality of service (QoS) over an MPLS backbone that uses traffic engineering. Bandwidth pools assigned to tunnel interfaces ensure that critical data is associated with a tunnel that has enough bandwidth to transport data over the MPLS network. For more information about this feature, refer to the following URL:

The Fast Reroute (FRR) link protection feature of MPLS traffic engineering provides link protection to label-switched paths (LSPs). MPLS traffic engineering automatically establishes and maintains LSPs across the backbone using Resource ReSerVation Protocol (RSVP). Paths for LSPs are calculated at the headend, based on the LSP resource requirements and available network resources such as bandwidth. Under failure conditions, the headend determines a new route for the LSP. This provides for the optimal use of resources. However, due to messaging delays, recovery at the headend is not as quick as recovery at the point of failure. For more information about this feature, refer to the following URL:

The Border Gateway Protocol (BGP) Multipath Load Sharing for external BGP (eBGP) and internal BGP (iBGP) in a Multiprotocol Label Switching (MPLS) Virtual Private Network (VPN) feature allows you to configure multihomed autonomous systems and provider edge (PE) routers to:

The eiBGP Multipath Load Sharing feature performs unequal cost load balancing by default by selecting BGP paths that do not have an equal cost of the Interior Gateway Protocol (IGP).

Interactive traffic (Telnet, voice over IP) is susceptible to increased latency and jitter when the network processes large packets (for example, LAN-to-LAN FTP transfers traversing a WAN link), especially as they are queued on slower links. The Link Fragmentation and Interleaving (LFI) feature reduces delay and jitter on slower-speed links by breaking up large datagrams and interleaving low-delay traffic packets (such as voice) with the smaller packets resulting from the fragmented datagram. LFI was designed especially for lower-speed links where serialization delay is significant.

The single rate 3-Color Marker feature meters an IP packet stream and marks its packets different colors, based on the Committed Information Rate (CIR) and two associated burst sizes: Committed Burst Size (CBS) and Excess Burst Size (EBS). CIR is measured in bytes of IP packets per second (and it includes the IP header, but not link specific headers). CBS and EBS are measured in bytes.

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Green (conforming)—Packet size is at most Bc or CBS and within the CIR allowance.

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Yellow (exceeding)—Packet size is greater than the CIR allowance but is at most Be or EBS bytes and within the available surplus.

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Red (violating)—Packet size is greater than both the CIR allowance and the available surplus. This is because either the packet's size exceeds Be or EBS or because a previous packet used some of the surplus and the traffic since then has not slowed sufficiently to acquire the surplus needed for the current packet.

The marker starts with a surplus equal to Be or EBS, and replenishes the surplus by the amount of unused CIR allowance until the surplus reaches Be or EBS.

MIB capabilities on the Cisco 10000 series router have been enhanced as follows:

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Support was verified for the following MIBs: ATM-MIB, CISCO-AAL5-MIB, CISCO-ATM-EXT-MIB, SONET-MIB, RFC1315-MIB, CISCO-FRAME-RELAY-MIB, and CISCO-RF-MIB.

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Support was added for MPLS-LSR-MIB mplsInSegmentOctets and mplsInSegmentOctets.

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MIBs were enhanced to support the Cisco 10000 series router high-availability feature.

For more information about the MIB capabilities, refer to the Cisco 10000 Series Router Broadband MIB Specifications Guide at the following URL:

Use the SNMP trap filtering feature to filter linkDown traps so that SNMP only sends a linkDown trap if the main interface goes down. If a Cisco 10000 series Internet router interfaces goes down, all of its subinterfaces go down, which results in numerous linkDown traps for each subinterface. This feature filters out those subinterface traps. This feature is turned off by default.

Limitations and Restrictions

Ensure that the Fast Ethernet NME port on the PRE is configured for auto-negotiation mode, which is the system default. Duplex mode can cause problems, such as flapping. If the port is experiencing such problems and has been configured for duplex mode, use the no half-duplex or no full-duplex command to disable duplex mode.

It is important that you limit the rate that system messages are logged by the Cisco 10000 series router. This helps to avoid a situation in which the router becomes unstable and the CPU is overloaded. To control the output of messages from the system, use the logging rate-limit command.

We recommend that you configure the logging rate-limit command as follows. This rate-limits all messages to the console to 10 per second, except for messages with critical priority (level 3) or greater.

For more information on the logging rate-limit command, refer to the Cisco IOS Configuration Fundamentals Command Reference.

The following limitations apply to the Cisco 10000 series router implementation of Frame Relay:

The following limitations and restrictions apply to the Cisco 10000 series router nested policy feature:

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For additional restrictions and limitations on creating nested policies, refer to the Cisco 10000 Series Router Quality of Service Configuration Guide at the following URL:

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The nested-policy shape rate is reserved for nested-policy traffic only. Excess bandwidth is not used for other traffic.

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DotP marking is not supported, nor is 802.1P (including matching and marking the 802.1P header).

Note

The actual shape rate applied to nested-policy traffic might differ from that specified in the policy. For example, a specified shape rate of 10.5 Mbps might be mapped to 11 Mbps. Use the command show policy-map interface to determine the actual shape rate.

Cisco IOS software running on the Cisco 10000 series router has multiple queues for all classes of traffic over high-speed interfaces. The software selects a queue based on the source and destination address for the packet. This ensures that a traffic flow always uses the same queue and the packets are transmitted in proper order.

When the router is installed in a real network, the high-speed interfaces work efficiently to spread traffic flow equally over the queues. However, using single traffic streams in a laboratory environment may result in less-than-expected performance. To ensure accurate test results, you should test the throughput of the gigabit Ethernet, POS, or ATM uplink with multiple source or destination addresses.

Tip

To determine if traffic is being properly distributed, use the show hardware pxf cpu queue command.

Important Notes

Unlike other Cisco routers, on the Cisco 10000 series Internet router, the Cisco Discovery Protocol (CDP) is disabled by default. You can enable CDP on an interface using the cdp enable command.

You can run up to 4000 Frame Relay sessions or 4000 PPP sessions, and you can configure up to 800 Border Gateway Protocol (BGP) peers on the Cisco 10000 series Internet router. The router also supports up to 512 Multilink Point-to-Point (MLP) protocol sessions and up to 1024 MLP bundles.

To run Cisco IOS Release 12.0(22)S and later releases on the Cisco 10000 series router, the performance routing engine (PRE) installed in the chassis must be the PRE (Part Number ESR-PRE1). You can verify which PRE is installed in the chassis by using the show version command.

Note The Cisco 10000 series router does not support mixing two different PRE revisions in the same chassis. Do not install a PRE (Part Number ESR-PRE) and PRE (Part Number ESR-PRE1) in the same chassis.

Unlike other Cisco routers, if you insert a new or different line card into a Cisco 10000 series router chassis slot that previously had a line card installed, the line card initially reports that it is administratively up.

To ensure that the performance routing engine (PRE) microcode has adequate IP address space, use IP addresses in a contiguous address space. Also, use the ip unnumbered command on the RBE subinterface.

Open Caveats—Cisco IOS Release 12.0(23)SX4

Table 1 Open Caveats in Cisco IOS Release 12.0(23)SX4
Caveat	Description
General
CSCdz02942	After a stateful switchover (SSO) in a redundant PRE system, the MIB objects ifLastChange (IF-MIB) and atmVclLastChange (ATM-MIB) might not match sysUpTime.0 (MIB-2), although they should. This problem can occur: •After a second switchover •When the standby PRE is reset, followed by a switchover •When the standby PRE is inserted in the chassis later, after insertion of the primary PRE Workaround: None.
CSCdz26218	PXF diversion statistics do not clear when you issue the microcode reload all command, although they should. Workaround: Reload the Cisco IOS software.
CSCdz29077	After you issue the shutdown and no shutdown commands on a Cisco channelized OC-12 line card, the show controller t3 command incorrectly displays the T3 controller as Down. The controller is really Up. Workaround: Issue the shutdown command, wait several seconds, and then issue the no shutdown command on the SONET interface. This sets the T3 interface to Up in the show controller t3 command.
CSCdz32795	A routing policy does not count packets of 65 bytes or larger. The packets are transported, but not counted. Workaround: None.
CSCdz35018	A traceback message appears during testing of IP multicast. Workaround: None.
CSCdz54597	The Cisco 4-port channelized OC-3 line card experiences low throughput and packet loss when configured with 252 SONET interfaces (VT E1 unframed). Workaround: None.
CSCdz56101	On a Cisco channelized 4-port STM-1 line card with 756 interfaces, each at 512 Kbps with SDH framing and AU-4-TUG-3 controllers, the line protocol fails to initialize for several interfaces. Workaround: None.
CSCea66250	When an ICMP echo request (ping) packet is received on an interface that has access control list (ACL) logging enabled, the PXF can fail and a Local Bus Exception error message appears. Workaround: Disable ACL logging on the interface.
CSCea74742	When the traffic policing max burst size is set to a small value, the policing exceed function does not work correctly. Workaround: None.
eiBGP Multipath Load Sharing
CSCdy88837	If eiBGP multipath is configured in an MPLS network and one of the links is configured as eBGP, traffic may not be distributed through all links. This problem occurs when MAX Paths EIBGP is enabled under the address family. In this case, the IP BGP table indicates multiple routes to a destination network (eBGP and iBGP paths), but the IP Route VPN table only shows iBGP paths. Workaround: Disable eiBGP and use the weight command to forward traffic through eBGP or iBGP paths.
CSCdz10264	When the router is configured as a provider edge (PE) router with 100 VPNs, the number of packets reported at an ingress port might not reflect the actual number of packets forwarded by the router. This problem occurs on gigabit Ethernet (gigE) line cards when a gigE port is configured as a subinterface on a VLAN, and traffic is sent to each VLAN ID from another router. Workaround: None.
CSCdz26257	Traffic might not be load-balanced through iBGP paths when MPLS eiBGP or iBGP max-paths is configured. For example, two iBGP paths might exist to the next hop but the PXF only forwards traffic through one of them. This means one of the links is not being used. Workaround: If the router is forwarding traffic through the slower link, you can shut down the slower link to allow the faster link to forward traffic.
Link Fragmentation and Interleaving
CSCdy75500	The show frame-relay fragment command truncates the Frame Relay interface name for Cisco channelized 4-port STM-1 line cards. Workaround: None.
CSCdz27628	When class-based weighted fair queuing (CBWFQ) is used with LFI enabled and multiple queues are configured for a link, packets are dropped from underloaded queues rather than overloaded (congested) queues. This problem occurs when traffic with different packet sizes is sent to different queues, which causes fragmentation on some queues but not others. Workaround: Be sure to use a priority queue when you enable LFI.
CSCdz42829	When LFI is enabled, the show frame pvc command sometimes shows invalid counts for input and output packets and bytes. Workaround: None.
SNMP and MIBs (see also General)
CSCdz50531	The SONET-MIB does not update the intervals in the sonetVTIntervalTable or sonetVTFarEndIntervalTable for channelized STM and channelized OC-12 AU-3 TU controllers. Workaround: None.
CSCdz65705	When SNMP trap filtering is enabled (snmp ifmib trap throttle), SNMP does not generate a notification when a subinterface is shut down, although it should. Workaround: None.
CSCea08828	When SNMP trap filtering is enabled on a Cisco 1-port channelized OC-12 line card, the T3 layer generates a linkDown trap when the SONET layer is shut down, although it should not. Workaround: None.
Stateful Switchover
CSCdy66774	After a stateful switchover (SSO), the first packet sent through UDP is lost. Workaround: Configure the router to check that the first IP packet has an ARP entry defined for its destination (which must be connected through a fast Ethernet interface). To do this, issue the following CLI command (where A.B.C.D is the destination IP address and H.H.H is the 48-bit hardware address): `conf t` `arp A.B.C.D H.H.H`

Resolved Caveats—Cisco IOS Release 12.0(23)SX4

The following problems have been fixed in Cisco IOS Release 12.0(23)SX4. For information about problems fixed in other Cisco IOS releases, refer to the appropriate Release Notes document located at the following URL:

When you delete an interface with an ACL configured and then add a new interface and configure an ACL on it, the following error message no longer appears:

If you modify the ACL or the microcode reloads, the router now processes the ACL correctly.

Using the Link Fragmentation Interleaving (LFI) feature in Cisco IOS Release 12.2(15)T1 or Cisco IOS Release 12.3(1) with multilink PPP (MLPPP) no longer results in corrupted outgoing IPCP packets. This problem did not occur when using the LFI feature in Cisco IOS Release 12.2(11)T6.

The line protocol on low speed interfaces no longer goes down unexpectedly. The Cisco 10000 series router now properly dequeues the packet priority queue on DS0 links.

On a Cisco 10000 series router with primary and secondary performance routing engines (PREs) configured, when you enter the frame-relay fragment fragment_size command in map-class configuration mode, the following error message no longer appears:

After you configure the frame-relay fragment fragment_size command, the configuration remains in effect, even when a PRE switchover occurs or when the router reloads.

When you enter the show route-map [policy-name] PBR command, the Cisco 10000 series router now correctly displays the number of packets or bytes for all of the route-maps configured in each PBR policy.

Obtaining Documentation

Cisco provides several ways to obtain documentation, technical assistance, and other technical resources. These sections explain how to obtain technical information from Cisco Systems.

Cisco.com

You can access the most current Cisco documentation on the World Wide Web at this URL:

Documentation CD-ROM

Cisco documentation and additional literature are available in a Cisco Documentation CD-ROM package, which may have shipped with your product. The Documentation CD-ROM is updated monthly and may be more current than printed documentation. The CD-ROM package is available as a single unit or through an annual subscription.

Registered Cisco.com users can order a single Documentation CD-ROM (product number DOC-CONDOCCD=) through the Cisco Ordering tool:

All users can order monthly or quarterly subscriptions through the online Subscription Store:

Ordering Documentation

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Registered Cisco.com users (Cisco direct customers) can order Cisco product documentation from the Networking Products MarketPlace:

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Nonregistered Cisco.com users can order documentation through a local account representative by calling Cisco Systems Corporate Headquarters (California, U.S.A.) at 408 526-7208 or, elsewhere in North America, by calling 800 553-NETS (6387).

Documentation Feedback

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Cisco Systems
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Obtaining Technical Assistance

Cisco provides Cisco.com, which includes the Cisco Technical Assistance Center (TAC) Website, as a starting point for all technical assistance. Customers and partners can obtain online documentation, troubleshooting tips, and sample configurations from the Cisco TAC website. Cisco.com registered users have complete access to the technical support resources on the Cisco TAC website, including TAC tools and utilities.

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Technical Assistance Center

The Cisco TAC is available to all customers who need technical assistance with a Cisco product, technology, or solution. Two levels of support are available: the Cisco TAC website and the Cisco TAC Escalation Center. The avenue of support that you choose depends on the priority of the problem and the conditions stated in service contracts, when applicable.

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Priority level 4 (P4)—You need information or assistance concerning Cisco product capabilities, product installation, or basic product configuration. There is little or no impact to your business operations.

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Priority level 3 (P3)—Operational performance of the network is impaired, but most business operations remain functional. You and Cisco are willing to commit resources during normal business hours to restore service to satisfactory levels.

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Priority level 2 (P2)—Operation of an existing network is severely degraded, or significant aspects of your business operations are negatively impacted by inadequate performance of Cisco products. You and Cisco will commit full-time resources during normal business hours to resolve the situation.

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Priority level 1 (P1)—An existing network is "down," or there is a critical impact to your business operations. You and Cisco will commit all necessary resources around the clock to resolve the situation.

Cisco TAC Website

The Cisco TAC website provides online documents and tools to help troubleshoot and resolve technical issues with Cisco products and technologies. To access the Cisco TAC website, go to this URL:

All customers, partners, and resellers who have a valid Cisco service contract have complete access to the technical support resources on the Cisco TAC website. Some services on the Cisco TAC website require a Cisco.com login ID and password. If you have a valid service contract but do not have a login ID or password, go to this URL to register:

If you are a Cisco.com registered user, and you cannot resolve your technical issues by using the Cisco TAC website, you can open a case online at this URL:

If you have Internet access, we recommend that you open P3 and P4 cases through the Cisco TAC website so that you can describe the situation in your own words and attach any necessary files.

Cisco TAC Escalation Center

The Cisco TAC Escalation Center addresses priority level 1 or priority level 2 issues. These classifications are assigned when severe network degradation significantly impacts business operations. When you contact the TAC Escalation Center with a P1 or P2 problem, a Cisco TAC engineer automatically opens a case.

To obtain a directory of toll-free Cisco TAC telephone numbers for your country, go to this URL:

Before you call, check with your network operations center to determine the level of Cisco support services to which your company is entitled: for example, SMARTnet, SMARTnet Onsite, or Network Supported Accounts (NSA). When you call the center, have your service agreement number and your product serial number available.

Obtaining Additional Publications and Information

Information about Cisco products, technologies, and network solutions is available from various online and printed sources.

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The Cisco Product Catalog describes the networking products offered by Cisco Systems, as well as ordering and customer support services. Access the Cisco Product Catalog at this URL:

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Cisco Press publishes a wide range of networking publications. Cisco suggests these titles for new and experienced users: Internetworking Terms and Acronyms Dictionary, Internetworking Technology Handbook, Internetworking Troubleshooting Guide, and the Internetworking Design Guide. For current Cisco Press titles and other information, go to Cisco Press online at this URL:

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Table Of Contents

Release Notes for the Cisco 10000 Series Internet Router for Cisco IOS Release 12.0(23)SX4

Contents

Cisco Security Advisory

System Requirements

Memory Requirements

Upgrading to a New Software Release

Upgrading Software from Earlier Cisco IOS Releases

Upgrading Software on Redundant PREs

New Features—Cisco IOS Release 12.0(23)SX4

New Features—Cisco IOS Release 12.0(23)SX

Limitations and Restrictions

Important Notes

Open Caveats—Cisco IOS Release 12.0(23)SX4

Resolved Caveats—Cisco IOS Release 12.0(23)SX4

Obtaining Documentation

Cisco.com

Documentation CD-ROM

Ordering Documentation

Documentation Feedback

Obtaining Technical Assistance

Cisco.com

Technical Assistance Center

Cisco TAC Website

Cisco TAC Escalation Center

Obtaining Additional Publications and Information

All other trademarks mentioned in this document or Web site are the property of their respective owners. The use of the word partner does not imply a partnership relationship between Cisco and any other company. (0304R)

Copyright � 2003, Cisco Systems, Inc.
All rights reserved.

Table Of Contents

Release Notes for the Cisco 10000 Series Internet Router for Cisco IOS Release 12.0(23)SX4

Contents

Cisco Security Advisory

System Requirements

Memory Requirements

Upgrading to a New Software Release

Upgrading Software from Earlier Cisco IOS Releases

Upgrading Software on Redundant PREs

New Features—Cisco IOS Release 12.0(23)SX4

New Features—Cisco IOS Release 12.0(23)SX

Limitations and Restrictions

Important Notes

Open Caveats—Cisco IOS Release 12.0(23)SX4

Resolved Caveats—Cisco IOS Release 12.0(23)SX4

Obtaining Documentation

Cisco.com

Documentation CD-ROM

Ordering Documentation

Documentation Feedback

Obtaining Technical Assistance

Cisco.com

Technical Assistance Center

Cisco TAC Website

Cisco TAC Escalation Center

Obtaining Additional Publications and Information

All other trademarks mentioned in this document or Web site are the property of their respective owners. The use of the word partner does not imply a partnership relationship between Cisco and any other company. (0304R)

Copyright � 2003, Cisco Systems, Inc.All rights reserved.

Copyright � 2003, Cisco Systems, Inc.
All rights reserved.