Release Notes for Cisco 7000 Family for Cisco IOS Release 11.2 P

January 12, 1998

This release note describes the features and caveats for the Cisco 7000 family of routers that support Cisco IOS Release 11.2 P, up to and including Release 11.2(11)P. For detailed software configuration information on the new features and Cisco IOS commands supported by Release 11.2 P, refer to the Feature Guide for Cisco IOS Release 11.2 P.

Prior to Cisco IOS Release 11.2, maintenance releases of major Cisco IOS software releases were used to deliver additional new features. Beginning with Cisco IOS Release 11.2, Cisco Systems provides several software release "trains" based on a single version of Cisco IOS software. Maintenance releases of the Major train software deliver fixes to software defects only, thus providing the most stable software for your network, for the features you need.

In addition to the Major train, there might be Early Deployment (ED) trains. One ED train--Release 11.2 P--delivers both fixes to software defects and support for new Cisco platforms and features.

This release note describes Release 11.2 P only and does not describe features that are available in Release 11.2 or other ED trains. For information about features in Release 11.2, refer to the Release Notes for Cisco IOS Release 11.2. For information about features in other ED trains, refer to the release notes for the specific ED train.

As of Release 11.2(8)P, release notes are product specific. That is, there are separate release notes for each product line. Therefore, this release note only contains information for the Cisco 7000 family of routers. For information about other Cisco products, refer to the specific product's release notes. For information on products supported in Cisco IOS Release 11.2 P prior to 11.2(8)P, refer to the Release Notes for Cisco IOS Release 11.2 P. For additional information on features supported in Cisco IOS Release 11.2 P, refer to the Cisco IOS Software Release 11.2 P Content and Platform Support Product Bulletin #553.

Use these release notes in conjunction with the Release Notes for Cisco IOS Release 11.2. The software caveats that apply to Release 11.2 also apply to Release 11.2 P.

This release note discusses the following topics:

• Documentation, page 2

• Platform Support for Release 11.2 P, page 3

• New Features in Release 11.2(11)P, page 5

• New Features in Release 11.2(10)P, page 6

• New Features in Release 11.2(9)P, page 7

• New Features in Release 11.2(8)P, page 7

• New Features in Release 11.2(7)P, page 7

• New Features in Release 11.2(6)P, page 11

• New Features in Release 11.2(5)P, page 11

• New Features in Release 11.2(4)P, page 13

• New Features in Release 11.2(3)P, page 13

• New Features in Release 11.2(2)P, page 13

• Cisco IOS Feature Sets, page 13

• Upgrading to a New Software Release, page 22

• Memory Requirements, page 22

• Important Notes, page 23

• Release 11.2 P Caveats, page 24

• Release 11.2(11)P Caveats, page 24

• Release 11.2(10)P Caveats/11.2(11)P Modifications, page 26

• Release 11.2(9)P Caveats/11.2(10)P Modifications, page 27

• Release 11.2(8)P Caveats/11.2(9)P Modifications, page 29

• Release 11.2(7)P Caveats/11.2(8)P Modifications, page 30

• Release 11.2(6)P Caveats/11.2(7)P Modifications, page 31

• Release 11.2(5)P Caveats/11.2(6)P Modifications, page 33

• Release 11.2(4)P Caveats/11.2(5)P Modifications, page 34

• Release 11.2(3)P Caveats/11.2(4)P Modifications, page 34

• Release 11.2(1)P Caveats/11.2(3)P Modifications, page 34

• Cisco Connection Online, page 35

• Documentation CD-ROM, page 36

Documentation

Refer to the Feature Guide for Cisco IOS Release 11.2 P for new or changed Cisco IOS software documentation specific to new features described in this release note. In this feature guide, new features are documented in their own sections, which include configuration tasks and also new and changed command reference pages. This feature guide supplements the Cisco IOS Release 11.2 configuration guide and command reference publications and provides feature documentation for all 11.2 P releases up to and including 11.2(11)P.

The printed version of the Feature Guide for Cisco IOS Release 11.2 P contains features up to Release 11.2(7)P. All features added after Release 11.2(7)P are available in the electronic (online) version of the feature guide only.

Cisco IOS Release 11.2 P documentation can be found on the Documentation CD-ROM. On the Documentation CD, the path is as follows:

Cisco Product Documentation: Cisco IOS Software Configuration: Cisco IOS Release 11.2:

• Feature Guide for Cisco IOS Release 11.2P

• Product-Specific Release Notes

• Cisco IOS Software Release 11.2 and 11.2P Caveats

On Cisco Connection Online (CCO), http://www.cisco.com/, the path is as follows:

Cisco Connection Online: Products and Ordering: Documentation: Cisco Documentation: Cisco Product Documentation: Cisco IOS Software Configuration: Cisco IOS Release 11.2:

• Feature Guide for Cisco IOS Release 11.2P

• Product-Specific Release Notes

• Cisco IOS Software Release 11.2 and 11.2P Caveats

For electronic documentation of Cisco IOS Release 11.2 features available on the Documentation CD-ROM, refer to the Cisco IOS Release 11.2 configuration guides and command references, which are located in the Cisco IOS Release 11.2 database. For more information, refer to the "Documentation CD-ROM" section later in this document.

You can also access Cisco technical documentation on the Web at http://www.cisco.com. For more information, refer to the "Cisco Connection Online" section later in this document.

Platform Support for Release 11.2 P

Cisco IOS Release 11.2 P supports the following Cisco 7000 family of routers:

• Cisco 7200 series (including the Cisco 7204 and Cisco 7206)

• Cisco 7500 series (including the Cisco 7505, Cisco 7507, and Cisco 7513)

• Cisco 7000 series routers (including the Cisco 7000 and Cisco 7010) upgraded with the 7000 Series Route Switch Processor (RSP7000) and 7000 Series Chassis Interface (RSP7000CI)

Table 1 summarizes the LAN interfaces supported on the Cisco 7000 family of routers.

Table 2 summarizes the WAN data rates and interfaces supported on the Cisco 7000 family of routers.

"Yes" means that a particular data rate or interface is supported. "No" means that it is not.

New Features in Release 11.2(11)P

The following new features are supported by the Cisco 7000 family of routers in Cisco IOS Release 11.2(11)P.

NPE-200 Network Processing Engine

The NPE-200 for Cisco 7200 series routers is now available. The network processing engine maintains and executes the system management functions for Cisco 7200 series routers. The network processing engine also shares the system memory and environmental monitoring function with the I/O controller. The NPE-200 has an R5000 microprocessor that operates at an internal clock speed of 200 megahertz (MHz), 4 MB of SRAM, and erasable programmable read-only memory (EPROM) for storing sufficient code for booting the Cisco IOS software.

RJ-45 Interface Support

Cisco 7200 series routers support a new I/O controller with an RJ-45 interface. An optional Fast Ethernet port is configurable for use at 100 megabits per second (Mbps) full-duplex or half-duplex (half duplex is the default). The Fast Ethernet port is equipped with either a single MII receptacle or an RJ-45 receptacle.

To support this new feature, the media-type interface command has been modified. The media-type interface command now supports two options:

New Features in Release 11.2(10)P

The following new features are supported by the Cisco 7000 family of routers in Cisco IOS Release 11.2(10)P.

PA-12E/2FE Ethernet Switch 10BASE-T and 100BASE-TX Port Adapters

The PA-12E/2FE Ethernet switch 10BASE-T and 100BASE-TX port adapters are available on Cisco 7200 series routers. The PA-12E/2FE port adapter provides up to twelve 10-Mbps and two 10/100-Mbps switched Ethernet (10BASE-T) and Fast Ethernet (100BASE-TX) interfaces for an aggregate bandwidth of 435 Mbps, full-duplex. For more information on the PA-12E/2EF port adapter, refer to the publication PA-12E/2EF Ethernet Switch 10BASE-T and 100BASE-TX Port Adapter Installation and Configuration that accompanies the hardware and the feature module in the Feature Guide for Cisco IOS Release 11.2.

Encryption over Frame Relay on VIP

You can use any type of encapsulation with IP encryption, except as follows: If you have a second-generation Versatile Interface Processor (VIP2) with a serial interface, encryption will not work for traffic on the serial interface unless you use the Point-to-Point Protocol (PPP), High-Level Data Link Control (HDLC) protocol, or Frame Relay protocol. For example, you cannot use encryption if you have X.25 or SMDS configured for the serial interface of a VIP2.

This feature was introduced in Cisco Release 11.2(7)P. Encryption over Frame Relay on a VIP2 is available in Cisco IOS Release 11.2(7)P or later.

POS Command Enhancements

• The pos internal-clock interface command has been replaced by the clock source interface configuration command.

• The new interface command pos scramble-atm enables SONET payload scrambling on a POS interface. SONET payload scrambling applies a self-synchronous scrambler (x^43+1) to the Synchronous Payload Envelope (SPE) of the interface to ensure sufficient bit transition density.

Web Cache Control Protocol

The Web Cache Control Protocol (WCCP) feature allows you to use a Cisco Cache Engine to handle web traffic, thus reducing transmission costs and downloading time. This traffic includes user requests to view pages and graphics on World Wide Web servers, whether internal or external to your network, and the replies to those requests.

When a user (client) requests a page from a web server, the router sends the request to a Cisco Cache Engine. If the cache engine has a copy of the requested page in storage, the engine sends the user that page. Otherwise, the engine gets the requested page and the objects on that page from the web server, stores a copy of the page and its objects (caches them), and forwards the page and objects to the user.

WCCP transparently redirects HTTP requests from the intended server to a Cisco Cache Engine. End users do not know that the page came from the cache engine rather than the originally requested web server.

The publication Using the Cisco Cache Engine contains detailed information about the Cisco Cache Engine and discusses alternative network configurations. For more information on WCCP, refer to the feature module in the Feature Guide for Cisco IOS Release 11.2.

New Features in Release 11.2(9)P

There are no new features supported by the Cisco 7000 family of routers in Cisco IOS Release 11.2(9)P.

New Features in Release 11.2(8)P

The following new feature is supported by the Cisco 7000 family of routers in Cisco IOS Release 11.2(8)P.

ATM Cable Interface Processor on Cisco 7500 Series Routers

The Asynchronous Transfer Mode (ATM) Cable Interface Processor (ACIP) is available on Cisco 7500 series routers. The ACIP provides a single, full-duplex ATM network interface for connection to a TeraLink 1000 cable headend, or through a Cisco Lightstream 1010 ATM switch or other external ATM network equipment at data rates up to 155 Mbps bidirectionally. The ACIP has one multimode duplex SC-type connector or two single SC-type connectors that support Synchronous Optical Network/Synchronous Digital Hierarchy (SONET/SDH) multimode fiber optic cable (STS-3C or STM-1).

The ACIP supports the following features:

• Internet Protocol (IP).

• Multiple rate queues.

• Reassembly of up to 512 buffers simultaneously (each buffer represents a packet).

• Up to 2,048 virtual circuits (VCs).

• Transfer rates per virtual path identifier (VPI) limited to fixed values provided by the cable headend.

• Exception queue used for event reporting such as CRC errors.

• Raw queue used for all raw traffic over the ATM network (raw traffic includes Operation, Administration, and Maintenance [OAM] cells and Interim Local Management Interface [ILMI] cells). ATM signaling cells are not considered raw traffic.

New Features in Release 11.2(7)P

The following new features are supported by the Cisco 7000 family of routers in Cisco IOS Release 11.2(7)P.

PA-8B-ST and PA-4B-U Basic Rate Interface Port Adapters

Basic Rate Interface (BRI) Integrated Services Digital Network (ISDN) port adapters (PA-8B-ST and PA-4B-U) are available on Cisco 7200 series routers.

The PA-8B-ST port adapter provides up to eight S/T-type BRI interfaces used to connect to an ISDN wide-area network through an external network terminator 1 (NT1) device. The PA-4B-U provides up to four BRI interfaces used to connect to an ISDN wide-area network through its internal NT1 device. Each PA-8B-ST and PA-4B-U interface consists of two bearer (B) channels that can transmit and receive data at the rate of 64 kbps, full-duplex, and one data (D) channel that can transmit and receive data at the rate of 16 kbps, full-duplex. The interfaces use an RJ-45 receptacle and standard straight-through twisted pair cable.

The B channels are used for transmitting user data. The D channel is used for call setup control and network connection teardown, and provides the communication from the router to the ISDN switch. The B and D channels are presented to the system as serial interfaces that support High-Level Data Link Control (HDLC) and Point-to-Point Protocol (PPP) encapsulation. The PA-8B-ST and PA-4B-U port adapters also support dial-on-demand routing (DDR).

Half-Duplex and Bisync for Synchronous Serial Port Adapters on Cisco 7200 Series Routers

The synchronous serial port adapters (PA-8T-V35, PA-8T-X21, PA-8T-232, and PA-4T+) on Cisco 7200 series routers support half-duplex and binary synchronous communications (Bisync). Bisync is a character-oriented data link layer protocol for half-duplex applications. In half-duplex mode, data is sent one direction at a time. Direction is controlled by handshaking the Request To Send (RTS) and Clear To Send (CTS) control lines.

Particle-Based Transparent Bridging on Cisco 7200 Series Routers

Particle-based transparent bridging (TRB) adds scatter-gather capability to transparent bridging by default to improve performance on Cisco 7200 series routers.

Particles represent a communications data packet as a collection of noncontiguous buffers. The traditional Cisco IOS packet has a packet type control structure and a single, contiguous data buffer. A particle packet has the same packet-type control structure, but also maintains a queue of particle-type structures, each of which manages its own block.

This scatter-gather architecture provides the following advantages:

• Allows drivers to use memory more efficiently (especially when using media that has a large maximum transmission unit [MTU]). For example, Token Ring buffers could be 512 bytes rather than 16 KB.

• Allows concurrent use of the same region of memory. For example, on IP multicast a single packet is received and sent out on multiple interfaces simultaneously.

• Allows insertion or deletion of memory at any location in a packet (not just at the beginning or end).

Fast-Switched Fragmented IP Packets on Cisco 7200 Series Routers

Fragmented IP packets are now fast switched rather than process switched by default to improve performance on Cisco 7200 series routers.

Fast-Switched SMRP Packets on Cisco 7200 Series Routers

Simple Multicast Routing Protocol (SMRP) packets are now fast switched rather than process switched by default to improve performance on Cisco 7200 series routers.

Turbo Flooding of UDP Datagrams on Cisco 7200 Series Routers

Turbo flooding is now supported on Cisco 7200 series routers. Turbo flooding speeds up flooding of User Datagram Protocol (UDP) datagrams using the spanning-tree algorithm. This feature is useful for quickly downloading periodic updates from a server to multiple clients in an environment where updates are frequent and speed and latency are primary considerations.

Next-Generation Route Switch Processor (RSP4) on Cisco 7500 Series Routers

The next-generation Route Switch Processor (RSP4) provides improved performance on Cisco 7500 series routers. The RSP4 uses a 200-MHz R5000 processor with twice the primary cache and a 512-KB secondary cache to greatly improve performance. The biggest increases in performance are in process-level switching and other process-level tasks (for example, route calculations) where the RSP4 is between two and four times faster than an RSP2. Fast-switching performance is also improved. The RSP4 supports the high system availability (HSA) feature and can be used in combination with an RSP2 or another RSP4.

Packet OC-3 Interface Processor

The Packet OC-3 Interface Processor (POSIP) is available on Cisco 7500 series routers and on Cisco 7000 series routers with the 7000 Series Route Switch Processor (RSP7000) and 7000 Series Chassis Interface (RSP7000CI).

The POSIP is a fixed-configuration interface processor that uses second-generation Versatile Interface Processor (VIP2) technology. The POSIP provides a single 155.520-Mbps, OC-3 physical layer interface for packet-based traffic. This OC-3 interface is fully compatible with SONET and SDH network facilities and is compliant with RFC 1619, "PPP over SONET/SDH," and RFC 1662, "PPP in HDLC-like Framing." The Packet-Over-SONET specification is primarily concerned with the use of the PPP encapsulation over SONET/SDH links.

Channelized T3 Interface Processor Feature Enhancements

You can now perform the following new tasks on the Channelized T3 Interface Processor (CT3IP) available on Cisco 7500 series routers and on Cisco 7000 series routers with the 7000 Series Route Switch Processor (RSP7000) and 7000 Series Chassis Interface (RSP7000CI):

• Configure Maintenance Data Link (MDL) messages

• Enable performance monitoring via Facility Data Link (FDL) per ANSI T1.403

• Generate bit error rate testing (BERT) test patterns

• Enable remote FDL loopbacks

• Support SNMP MIB per RFC 1406 and RFC 1407

100VG-AnyLAN Port Adapter

The 100VG-AnyLAN port adapter (PA-100VG) is available on Cisco 7500 series routers, Cisco 7200 series routers, and on Cisco 7000 series routers with the 7000 Series Route Switch Processor (RSP7000) and 7000 Series Chassis Interface (RSP7000CI).

The PA-100VG provides a single interface compatible with and specified by IEEE 802.12 to support 100 Mbps over Category 3 or Category 5 unshielded twisted-pair (UTP) cable with RJ-45 terminators. The PA-100VG supports 802.3 Ethernet packets and can be monitored with the IEEE 802.12 Interface MIB.

PA-4R-FDX Token Ring Full-Duplex Port Adapter

The Token Ring full-duplex port adapter (PA-4R-FDX) is available on Cisco 7500 series routers, Cisco 7200 series routers, and Cisco 7000 series routers with the 7000 Series Route Switch Processor (RSP7000) and 7000 Series Chassis Interface (RSP7000CI).

The PA-4R-FDX provides up to four IBM Token Ring or IEEE 802.5 Token Ring interfaces that can be set for 4- or 16-Mbps half-duplex or full-duplex operation and early token release. The default for all interfaces is half-duplex 4-Mbps operation with early token release disabled. The PA-4R-FDX connects over Type 1 lobe or Type 3 lobe cables and provides a DB-9 (PC-type) receptacle.

PA-A1-OC3MM and PA-A1-OC3SM ATM Port Adapters

Asynchronous Transfer Mode (ATM) port adapters (PA-A1-OC3MM and PA-A1-OC3SM) are available on Cisco 7500 series routers, Cisco 7200 series routers, and on Cisco 7000 series routers with the 7000 Series Route Switch Processor (RSP7000) and 7000 Series Chassis Interface (RSP7000CI).

The ATM port adapter provides a single SONET/SDH OC-3 full-duplex interface (either multimode or single-mode intermediate reach) and supports data rates of up to 155 Mbps bidirectionally. The ATM port adapter connects to a SONET/SDH multimode or SONET/STC-3C single-mode optical fiber cable (STS-3C or STM-1 physical layer) to connect the router to an external DSU (an ATM network). The ATM port adapter supports the following features:

• Segmentation and reassembly (SAR) of up to 512 buffers simultaneously, where each buffer represents a packet

• Up to 256 transmit buffers for simultaneous fragmentation

• Up to 2,048 SAR virtual circuits (VCs)

• ATM adaptation layer (AAL) 5

• Operation, Administration, and Maintenance (OAM) cells

PA-2CE1/PRI-75, PA-2CE1/PRI-120, and PA-2CT1/PRI Channelized E1 and T1 Port Adapters

Channelized E1 and T1 Primary Rate Interface (PRI) Integrated Services Digital Network (ISDN) port adapters (PA-2CE1/PRI-75, PA-2CE1/PRI-120, and PA-2CT1/PRI) are available on Cisco 7500 series routers, Cisco 7200 series routers, and on Cisco 7000 series routers with the 7000 Series Route Switch Processor (RSP7000) and 7000 Series Chassis Interface (RSP7000CI).

The PA-2CE1/PRI-120 (balanced 120 ohm) and PA-2E1/PRI-75 (unbalanced 75 ohm) provide up to two channelized E1 interfaces to connect to channel service units (CSUs), and can transmit and receive data bidirectionally at the E1 rate of 2.048 Mbps. The PA-2CT1/PRI provides up to two channelized T1 interfaces to connect to CSUs, and can transmit and receive data bidirectionally at the T1 rate of 1.544 Mbps. The interfaces use a 15-pin, D-shell receptacle. The PA-2CE1/PRI-75 and PA-2E1/PRI-120 use G.703 serial interface cables, and the PA-2CT1/PRI uses standard serial cables (null-modem and straight-through).

Data Encryption Service Adapter

The data encryption service adapter (ESA) is available on Cisco 7500 series routers, Cisco 7200 series routers, and on the Cisco 7000 series routers with the 7000 Series Route Switch Processor (RSP7000) and 7000 Series Chassis Interface (RSP7000CI). (ESAs require VIP2 model VIP2-40.)

The ESA provides encryption processing to offload some of the encryption processing from the router's main processor and to improve performance. Encryption and authentication are provided by a software service called a crypto engine. The ESA provides the encryption mechanisms required to perform data encryption using a 40-bit or 56-bit Data Encryption Standard (DES) configured through the crypto engine. The ESA uses Public Key (PK) technology based on the concept of the Protected Entity (PE) and employs the DES and the Digital Signature Standard (DSS) to ensure that secure data and information can be transferred between similarly equipped hosts on your network.

For detailed information on encryption, refer to the "Configuring Network Data Encryption with Router Authentication" chapter in the Security Configuration Guide.

Clock Rate Command Enhancements

The clock rate interface command has been enhanced for the synchronous serial port adapters (PA-8T-V35, PA-8T-X21, PA-8T-232, and PA-4T+) on Cisco 7500 series routers, on Cisco 7200 series routers, and on Cisco 7000 series routers with the 7000 Series Route Switch Processor (RSP7000) and 7000 Series Chassis Interface (RSP7000CI). For these port adapters, a nonstandard clock rate can be used. The clock rate you enter is rounded (if needed) to the nearest value that your hardware can support.

New Features in Release 11.2(6)P

There are no new features supported by the Cisco 7000 family of routers in Cisco IOS Release 11.2(6)P.

New Features in Release 11.2(5)P

The following new features are supported by the Cisco 7000 family of routers in Cisco IOS Release 11.2(5)P.

SA-Comp/1 and SA-Comp/4 Data Compression Service Adapters

The SA-Comp/1 and SA-Comp/4 data compression service adapters (CSAs) are available on Cisco 7500 series routers, on Cisco 7200 series routers, and on Cisco 7000 series routers with the 7000 Series Route Switch Processor (RSP7000) and 7000 Series Chassis Interface (RSP7000CI). (CSAs require VIP2 model VIP2-40.)

These service adapters provide high-performance, hardware-based data compression capabilities via simultaneous Stacker compression data compression algorithms with independent full-duplex compression and decompression capabilities on Point-to-Point Protocol (PPP) encapsulated packets.

Channelized T3 Interface Processor

The Channelized T3 Interface Processor (CT3IP) is available on Cisco 7500 series routers and Cisco 7000 series routers with the 7000 Series Route Switch Processor (RSP7000) and 7000 Series Chassis Interface (RSP7000CI).

The CT3IP is a fixed-configuration interface processor based on the second-generation Versatile Interface Processor (VIP2). The CT3IP has four T1 connections via DB-15 connectors and one DS3 connection via BNC connectors. Each DS3 interface can provide up to 28 T1 channels (a single T3 group). Each channel is presented to the system as a serial interface that can be configured individually. The CT3IP can transmit and receive data bidirectionally at the T1 rate of 1.536 Mbps. The four T1 connections use 100-ohm, twisted-pair serial cables to external channel service units (CSUs) or to a MultiChannel Interface Processor (MIP) on the same router or on another router. For wide-area networking, the CT3IP can function as a concentrator for a remote site.

FDDI Full-Duplex Single-Mode and Multimode Port Adapters

Fiber Distributed Data Interface (FDDI) full-duplex single-mode and multimode port adapters (PA-F/FD-SM and PA-F/FD-MM) are available on Cisco 7500 series routers, on Cisco 7200 series routers, and on Cisco 7000 series routers with the 7000 Series Route Switch Processor (RSP7000) and 7000 Series Chassis Interface (RSP7000CI).

These port adapters provide an interface for both single-mode and multimode fiber-optic cable. Two physical ports are available with either single-mode SC-type or multimode MIC receptacles. Each port adapter's FDDI connection allows a maximum aggregate bandwidth of 200 Mbps per the FDDI standard.

High-Speed Serial Interface Port Adapters

The High-Speed Serial Interface (HSSI) port adapter (PA-H Rev. B) is available on Cisco 7500 series routers, on Cisco 7200 series routers, and on Cisco 7000 series routers with the 7000 Series Route Switch Processor (RSP7000) and 7000 Series Chassis Interface (RSP7000CI). The PA-H provides one high-speed synchronous serial interface.

Although the PA-H was introduced in Cisco Release 11.2(5)P, the minimum Cisco IOS Release required by the PA-H is Release 11.2(7)P and Release 11.1(12)CA.

For additional information on the PA-H and PA-2H (the PA-2H provides two high-speed synchronous serial interfaces) port adapters, refer to the Field Notice: HSSI Port Adapters publication on CCO at the following location:

http://www.cisco.com/warp/customer/770/

Synchronous Serial Port Adapters

The synchronous serial port adapters (PA-8T-V35, PA-8T-X21, PA-8T-232, and PA-4T+) are available on Cisco 7500 series routers, on Cisco 7200 series routers, and on Cisco 7000 series routers with the 7000 Series Route Switch Processor (RSP7000) and 7000 Series Chassis Interface (RSP7000CI).

The PA-8T-V35, PA-8T-X21, PA-8T-232 port adapters provide up to eight synchronous serial interfaces, and the PA-4T+ provides up to four synchronous serial interfaces. Each port on the PA-4T+ supports any of the available interface types: Electronics Industries Association/Telecommunications Industries Association (EIA/TIA)-232, EIA/TIA-449, V.35, X.21, and EIA-530.

RSP Fragmented IP Packets Optimum or Flow Switched

To improve performance, fragmented IP packets are now optimum or flow switched (depending on which switching method is enabled) rather than being process switched on Cisco 7500 series routers and on Cisco 7000 series routers with the 7000 Series Route Switch Processor (RSP7000) and 7000 Series Chassis Interface (RSP7000CI).

Selective Packet Discard

When in severe overload conditions, routers that cannot keep up with the incoming packet stream must drop packets. If no intelligence is applied to choosing which ones to discard, this will impact the stability of routing protocols. This feature applies some simple choices to selectively discard packets likely to be unimportant for routing and interface stability. Selective Packet Discard (SPD) is enabled by default; there are no commands or configuration tasks required.

New Features in Release 11.2(4)P

There are no new features supported by the Cisco 7000 family of routers in Cisco IOS Release 11.2(4)P.

New Features in Release 11.2(3)P

There are no new features supported by the Cisco 7000 family of routers in Cisco IOS Release 11.2(3)P.

New Features in Release 11.2(2)P

There are no new features supported by the Cisco 7000 family of routers in Cisco IOS Release 11.2(4)P.

Cisco IOS Feature Sets

This section lists Cisco IOS software feature sets available for the Cisco 7000 family of routers in Cisco IOS Release 11.2 P.

For a complete list of Release 11.2 features that apply to platforms not mentioned in this release note, refer to the specific product's release notes and the Release Notes for Cisco IOS Release 11.2.

Release 11.2 P supports the same feature sets as Release 11.2, but it might also have new features supported by the Cisco 7000 family of routers.

Table 4 uses the feature set matrix symbols in Table 3 to identify features:

Cisco IOS images with 40-bit Data Encryption Standard (DES) support may legally be distributed to any party eligible to receive Cisco IOS software; 40-bit DES is not a cryptographically strong solution and should not be used to protect sensitive data.

Cisco IOS images with 56-bit DES are subject to International Traffic in Arms Regulations (ITAR) controls and have a limited distribution. Images to be installed outside the U.S. require an export license. Customer orders may be denied or subject to delay because of U.S. government regulations. Contact your sales representative or distributor for more information, or send e-mail to export@cisco.com.

Table 4 lists the standard feature sets supported in Release 11.2 P by the Cisco 7000 family of routers.

Feature Set Tables

Cisco IOS software is available in different feature sets depending on the platform. Table 5 lists the feature sets for Cisco 7200 series routers. Table 6 lists the feature sets for Cisco 7500 series routers and Cisco 7000 series with RSP7000 and RSP7000CI. Table 7 lists optional feature set licenses for the Cisco 7000 family of routers.

Upgrading to a New Software Release

For information on upgrading to a new software release, refer to the Cisco IOS Software Release Upgrade Paths and Packaging Simplification product bulletin #703.

You can also access this product bulletin on the Web at http://www.cisco.com. For more information, refer to the "Cisco Connection Online" section later in this document.

Memory Requirements

Table 8 describe the memory requirements for the feature sets on for the Cisco 7000 family of routers supported by Cisco IOS Release 11.2 P.

Cisco 7200 series routers are shipped with an 8-, 16-, or 20-MB Flash memory card. Cisco 7500 series routers and Cisco 7000 series routers with the RSP7000 and RSP7000CI are shipped with a 16- or 20-MB Flash memory card.

All feature sets for Cisco 7500 series and Cisco 7000 series routers with RSP7000 and RSP7000CI include VIP support.

Important Notes

This section contains important information about the Cisco IOS Release 11.2 P software. The following information describes the changes in release number for Release 11.2 P:

• Release 11.2(7a)P is an early deployment release of software to support Cisco 7200 series routers. Release 11.2(7a)P is the same as Release 11.2(7)P except the following defects have been resolved in Release 11.2(7a)P--CSCdj24132 and CSCdj19118.

• Release 11.2(6)P2 is an early deployment release of software to support Cisco 7200 series routers, Cisco 7500 series routers, and Cisco 7000 series routers with the RSP7000 and RSP7000CI. Release 11.2(6)P2 is the same as Release 11.2(6)P except the following defects have been resolved in Release 11.2(6)P2--CSCdj060068, CSCdj10028, CSCdj19231, and CSCdi67315. Release 11.2(6)P and Release 11.2(6)P1 software images were not released.

If you have an account on Cisco Connection Online (CCO), you can view the caveats mentioned above by using the bug search tools in the Bug Toolkit, such as the Bug Navigator.

Release 11.2 P Caveats

Refer to the Release Notes for Cisco IOS Release 11.2 publication for a list of the caveats that apply to Release 11.2. The caveats that apply to Cisco IOS Release 11.1 apply to Release 11.2 P.

The complete caveats against Release 11.2 are also available in the Cisco Documentation CD-ROM package. In the CD-ROM package, access the Cisco IOS 11.2 caveats in the Cisco IOS Release 11.2 database.

If you have an account on Cisco Connection Online (CCO), you can view additional caveats using the bug search tools in the Bug Toolkit, such as the Bug Navigator.

The following sections list caveats for Release 11.2 P that apply to the Cisco 7000 family of routers. For Release 11.2 P caveats for other Cisco products, refer to the specific product's release notes.

Release 11.2(11)P Caveats

This section describes possibly unexpected behavior by Release 11.2(11)P. Unless otherwise noted, these caveats apply to all 11.2 P releases up to and including 11.2(11)P.

Basic System Services

• We need better crash information to debug data/stack corruption crashes. The solution is to write crash information to default to bootflash:crashinfo in RSP and flash:crashinfo in RP. A series of test crash command selections are used to control and change the crashinfo collection mechanism. The crash information:

  • contains up to 32 KB in RSP and up to 20 KB in RP of errmsg log plus command history including config commands that user enters or "copy"

  • contains up to 32 KB on RSP and 20 KB on RP for all the following information:

  • crash stack trace

  • crash context

  • stack dump at crash

  • dump memory for each register containing "valid" RAM address

  • add errmsg display on invalid length of bcopy

  • add two commands to "test crash"

  • the sh stack command displays ("cat" as in UNIX) the bootflash:crashinfo file if there was a crash. User can also use the command copy flash tftp to dump the ASCII file bootflash/flash:crashinfo to a server.

  • the size is 16 KB of errmsg/command plus up to 16 KB of memory dump and other crash information. There is one 16 KB DRAM declared for this crash information collection mechanism.

Only Cisco 7000 series routers and RSP are activated with new crashinfo mechanism and the 16 KB. Cisco 4500 and others will see no difference. [CSCdj12951]

• Packets might not be forwarded correctly and can cause problems if fancy queueing (such as fair-queue) is enabled along with a compress service adaptor (CSA). [CSCdj64898]

Interfaces and Bridging

• After unplugging and plugging in the cable, the ATM interface ignores packets at a low packet rate. The workaround is to use the commands shut and no shut to reinitialize the interface. [CSCdj29724]

• When using E1 or T1 port adapters in channelized mode, the open timeslots should be assigned to an interface while the interface is shut down. If not, the router might affect other used timeslots and degrade their performance. [CSCdj48322]

• With serial links on VIP port adapters, users experience incrementing interface resets and serial line flaps under heavy load. The workaround is to turn off fair queueing. [CSCdj60813]

• A router crashes with a bus error when configuring source-route translational bridging. [CSCdj64480]

• The PA-8T port adapters on VIP2-40 interfaces flap intermittently when you enable hardware compression. This problem does not occur when compression is disabled. Note that hardware compression does not work with HDLC encapsulation in Cisco IOS Release 11.2(9)P, so PPP encapsulation is used in this case.

The 8-port mueslix-based serial port adapter can have intermittently flapping interfaces when used with a hardware compression port adapter. A possible workaround is to set the serial restart-delay to the maximum value, for example: interface serial 5/0/0 serial restart-delay 900 [CSCdj54162]

Novell IPX, XNS, and Apollo Domain

• Some service access points may be corrupted in the internal server list of the router when using Novell and the integrated routing and bridging feature. There is no workaround. [CSCdj70845]

Wide-Area Networking

• Because of a VIP2 problem, the ESA service adapter must be installed in port adapter slot 1 rather than slot 0 to function properly. Use the show diag command to indicate which slot the ESA is occupying in the VIP. [CSCdj06072]

• You may experience issues with the PRI hanging or busy when all channels are not in use. This is usually accompanied by the following console messages:

ISDN Se9/0/1:23: Error: CCB run away: 0x61D97560:
ISDN Se9/0/1:23: Error: CCB run away: 0x61C494F8:
ISDN Se9/0/1:23: Error: CCB run away: 0x61C494F8:

A CCB (Call Control Block) is an internal structure. You should only have one per call and B channel. For an example, interface Serial 9/0/1 has 60 CCBs.

The only workaround is to reset the controller manually. This can be done using the commands shut and no shut for the interface Serial0:XX or by reloading the router. [CSCdj48055]

• When configuring IRB to bridge over a serial interface with HDLC or Frame Relay encapsulation, AppleTalk does not work properly. Apple pings will fail, and zone information will not be transferred. [CSCdj67875]

• A Cisco 7200 series router can crash at the atmSig_input routine under normal operations. There is no known workaround. [CSCdj67880]

Release 11.2(10)P Caveats/11.2(11)P Modifications

This section describes possibly unexpected behavior by Release 11.2(10)P. Unless otherwise noted, these caveats apply to all 11.2 P releases up to and including 11.2(10)P. For additional caveats applicable to Release 11.2(10)P, see the caveats sections for newer 11.2 P releases. The caveats for newer releases precede this section.

All the caveats listed in this section are resolved in Release 11.2(11)P.

Basic System Services

• The input counters from the show frame-relay pvc command are not correctly updated if using optimum or Netflow switching. [CSCdj25759] [CSCdj26122]

IBM Connectivity

• A problem occurs when configuring source-route bridging on an FDDI interface on a Cisco 7200 series router. Using Cisco IOS 11.2 IP routing protocols on the same FDDI may not work properly. [CSCdj48508]

Interfaces and Bridging

• A problem has been identified in the code where a buffer size of 256K is used by the VIP if the VIP is a VIP2-20 and the port adapter is a PA-4R-FDX. The correct buffer size should be 512K, which is what the PA-4R-FDX driver is using. The difference in buffer size between the VIP and the PA-4R-FDX driver causes memory to be overwritten in the port adapter's transmit descriptor ring, then the transmit channel hangs, and the interface resets. [CSCdj49030]

IP Routing Protocols

• If your system reboots and displays output such as the following, upgrade to a Cisco IOS software release that contains the fix for this caveat. There is no known workaround.

Router# show version 
Cisco Internetwork Operating System Software
IOS (tm) 5200 Software (C5200-IS-L), Version 11.2(6)P, SHARED PLATFORM, RELEASE SOFTWARE (fc1)
Copyright (c) 1986-1997 by cisco Systems, Inc.
Compiled Mon 12-May-97 15:06 by tej 
Image text-base: 0x2202F744, data-base: 0x00005000
ROM: System Bootstrap, Version 11.1(474) [tamb 474], RELEASE SOFTWARE (fc1) 
ROM: 5200 Software (AS5200-BOOT-L), Version 11.1(474), RELEASE SOFTWARE (fc1) 
uptime is 5 minutes 
System restarted by bus error at PC 0x221AC3C0, address 0xFD0110EB 
cisco AS5200 (68030) processor (revision A) with 8192K/4096K bytes of memory. 
Processor board ID 03572663 
Bridging software. 
X.25 software, Version 2.0, NET2, BFE and GOSIP compliant. 
Primary Rate ISDN software, Version 1.0. 
Mother board without terminator card. 
1 Ethernet/IEEE 802.3 interface(s) 
50 Serial network interface(s) 
48 terminal line(s) 
2 Channelized T1/PRI port(s) 
128K bytes of non-volatile configuration memory. 
8192K bytes of processor board System flash (Read ONLY) 
4096K bytes of processor board Boot flash (Read/Write) 
Configuration register is 0x2102 

Router# show stack 
Minimum process stacks: 
Free/Size Name 
1820/2000 Reset ipc queue 
2648/4000 Init 
1648/2000 MAI Action Process 
1344/2000 Modem Autoconfigure 
2608/4000 Exec 
Interrupt level stacks: 
Level Called Unused/Size Name 
1 7105 1596/2000 CL-CD2430 transmit interrupts 
2 7223 1540/2000 CL-CD2430 receive interrupts 
3 24 1968/2000 Serial interface state change interrupt 
4 5698 1540/2000 Network interfaces 
5 10971 1896/2000 Console Uart 
6 2 1884/2000 DSX1 interface 
System was restarted by bus error at PC 0x221AC3C0, address 0xFD0110EB 5200 Software (C5200-IS-L), Version 11.2(6)P, SHARED PLATFORM, RELEASE SOFTWARE (fc1) 
Compiled Mon 12-May-97 15:06 by tej (current version) 
Image text-base: 0x2202F744, data-base: 0x00005000 
Stack trace from system failure: 
FP: 0x49EB48, RA: 0x221ACF1A 
FP: 0x49EB84, RA: 0x22195E4A 
FP: 0x49EC10, RA: 0x22199C64 
FP: 0x49ECFC, RA: 0x220ECF90 
FP: 0x49ED1C, RA: 0x220ED26E 
FP: 0x49ED48, RA: 0x22109BA0 
FP: 0x49ED70, RA: 0x222A7798 
FP: 0x49ED98, RA: 0x22109BA0 

[CSCdj36356]

• Entering the command no ipx routing then enabling eigrp with the command router eigrp can crash the router. This is a regression of CSCdj54141. [CSCdj53541]

Release 11.2(9)P Caveats/11.2(10)P Modifications

This section describes possibly unexpected behavior by Release 11.2(9)P. Unless otherwise noted, these caveats apply to all 11.2 P releases up to and including 11.2(9)P. For additional caveats applicable to Release 11.2(9)P, see the caveats sections for newer 11.2 P releases. The caveats for newer releases precede this section.

All the caveats listed in this section are resolved in Release 11.2(10)P.

Basic System Services

• On a Cisco 7000 with the RSP7000 or on a Cisco 7500 series router, optimum switching appears to negatively interfere with Frame Relay switching. An IP route cache is created and the switching is affected where connectivity between sites is lost. The behavior appears to be sporadic. [CSCdj26122]

• Certain commands are not present. The commands are:

  • copy bootflash {rcp | tftp}

  • copy flash {rcp | tftp}

A workaround for copying from flash memory to TFTP or RCP is to use

copy flash {rcp | tftp | file-id}

instead of the flash keyword. However, this does not work with the boot flash command. [CSCdj38964]

IBM Connectivity

• When enabling source-route translational bridging on a Cisco 7200 series router with Cisco IOS Release 11.2(8.3)P, the router runs out of I/O memory because of a buffer leak in small and middle buffers.

The workaround is to disable source-route translational bridging. [CSCdj40130]

• When enabling the source-route translational bridging feature, the router runs out of I/O memory because of a buffer leak in small and middle buffers.

The workaround is to disable source-route translational bridging. [CSCdj49533]

Interfaces and Bridging

• The internal clock on the ATM port adapter is not initialized properly. This causes a loopback ping to fail because neither end is providing the clock. [CSCdj24890]

• In a Cisco 7505 with RSP4, E1 port adapter, Release 11.1.14CA, custom queueing does not seem to work. [CSCdj47294]

• The ATM port adapter on a VIP2 platform does not function. The symptom is that the interface output gets stuck and the interface keeps resetting. [CSCdj51923]

IP Routing Protocols

• A routing node is removed from the IP cache Radix tree and then the buffer is freed, but somehow the node can still be traversed from the treetop and cause a crash (access after free). [CSCdj17314]

Wide-Area Networking

• The router configured with "isdn incoming-voice data 56" might wrongfully treat an incoming voice call as 64K. [CSCdj43717]

• A problem behaves in such a way that sometimes packets that are to be handled at the process level will end up in wrong queues. For instance, a routing packet could end up in a SSCOP queue, or a LANE queue, causing the SSCOP or LANE to operate abnormally and sometimes resulting in the interface flapping.

The problem occurs when an ATM port adapter is the third of the three fast Ethernet port adapters on a NPE-150, and its rx pool is forced to operate out of DRAM, or when an ATM port adapter is running in a NPE-100, where it is designed to operate out of DRAM. [CSCdj46634]

• An ATM port adapter connected to a Newbridge causes the laser to shut down after 8 seconds for 2 seconds. When you replace the ATM port adapter with an AIP, the laser works. [CSCdj46914]

Release 11.2(8)P Caveats/11.2(9)P Modifications

This section describes possibly unexpected behavior by Release 11.2(8)P. Unless otherwise noted, these caveats apply to all 11.2 P releases up to and including 11.2(8)P. For additional caveats applicable to Release 11.2(8)P, see the caveats sections for newer 11.2 P releases. The caveats for newer releases precede this section.

All the caveats listed in this section are resolved in Release 11.2(9)P.

Basic System Services

• Currently, Cisco 7200 series routers do not produce a core dump for the I/O memory region in any Cisco IOS release. Sometimes it is necessary to get this information if memory corruption is suspected. [CSCdj25189]

• When using distributed compression (VIP software compression), if input congestion occurs where an input buffer cannot be allocated, an illegal packet can be sent to the host causing unpredictable results including "output stuck" messages that result in a CBUS reset. This has been found on a VIP with four PRI interfaces doing distributed compression. The workaround is to turn off distributed compression. [CSCdj27067]

IBM Connectivity

• A rare condition happens when the underlying TCP layer sends an invalid frame. As such it does not add any instability to the release. [CSCdj27157]

• The SR/TLB feature does not function correctly; sessions through SR/TLB cannot be established. [CSCdj33360]

Interfaces and Bridging

• Call setup failures display the messages AIPREJCMD and AIP-3-FAILCREATEVC on an ATM port adapter (VIP). The problem is currently being investigated and a resolution will be available in the near future. [CSCdj25270]

• When more than 10 consecutive P-bit Severely Errored Seconds (PSESs) are received on the DS3, the CT3IP does not properly enter an unavailable state as defined in RFC 1407. When the PSESs desist, the counters are left in undefined states. [CSCdj26801]

• Cisco 7200 series routers do not support both IRB and multicast enabled. The following error messages might be generated if configured. [CSCdj28940]

%SYS-2-BADBUFFER: Attempt to use scattered buffer as contiguous src, ptr= 60C0C3BC, pool= 60C0AC28 
%ALIGN-3-CORRECT: Alignment correction made at 0x6026ADB0 reading 0x1AA0056 
%ALIGN-3-CORRECT: Alignment correction made at 0x6026B078 reading 0x1AA0046 

• The external/test port status display, shown in the output from the command show cont t3 is not reliable. Regardless of the port's real state, it may show

Ext1: OK, Ext2: OK, Ext3: OK, Test: OK 

If the state of any port changes sometime after booting, then all four ports will display their actual state. But if no such change happens, the display will continue to show OK, OK, OK, OK, regardless of the actual state. [CSCdj29082]

• The router will not respond to ARPs correctly when bridging IP on a channelized T1 interface. Therefore, Telnet sessions to and from the router will fail. [CSCdj31285]

• The ATM port adapter's PCI bus latency timer value is too small, which can cause some inefficiency on the PCI bus utilization on a VIP2. [CSCdj32880]

• Under certain circumstances, the Fast Ethernet interface could stop passing traffic. The reason for this behavior is being investigated. Resetting the interface in this condition with the shut/no shut command could result in the router reloading. Since the hanging problem doesn't occur any more, this DDTS only resolves the crash problem due to bus error when the shut/no shut command is issued while there is traffic on the Fast Ethernet interface. [CSCdj33727]

• When a virtual circuit creation fails because the maximum number of virtual paths are used up, it wastes the VCD being used and does not recycle it. That VCD remains unusable afterwards. [CSCdj34424]

IP Routing Protocols

• After the ip default-network command is issued, the default network route does not get sent to other routers in the network. There is no known workaround for this problem at this time. [CSCdj28362]

TN3270

• International (8-bit) characters will not echo when using TN3270. [CSCdj22231]

Release 11.2(7)P Caveats/11.2(8)P Modifications

This section describes possibly unexpected behavior by Release 11.2(7)P. Unless otherwise noted, these caveats apply to all 11.2 P releases up to and including 11.2(7)P. For additional caveats applicable to Release 11.2(7)P, see the caveats sections for newer 11.2 P releases. The caveats for newer releases precede this section.

All the caveats listed in this section are resolved in Release 11.2(8)P.

Interfaces and Bridging

• When you shutdown an ATM port adapter interface while it is transmitting large packets (512 bytes) at a high rate, there is a chance that it will cause the router to reload. Similarly, when you perform a shutdown while the interface is receiving traffic, there is a chance it will lose some buffers. [CSCdj09796]

• The 8T and 4T+ port adapter on the VIP could not send out a dial string. The fix was committed and it should be available at 11.1(13)CA and 11.2(8)P. Without the fix, the above synchronous interface (on VIP) can not support the Dial on Demand feature. [CSCdj12144]

• The VIP crashes due to a NULL pointer (in v0). [CSCdj20028]

• On the MultiChannel Interface Processor (MIP), when controller T1 X/X is configured for a PRI test on a Cisco 7000 series router instead of the serial X/X:23 interface getting configured, the Ethernet X/X:23 interface gets configured. After this point, any attempt to configure the interface causes the router to reload. This problem does not occur on Cisco 7500 series routers. [CSCdj20356]

• Compression with stac and HDLC had performance impact and encapsulation PPP didn't do any compression. [CSCdj23273]

• This update provides information on bug fixes for the CT3IP available in the Cisco IOS Release 11.1(12)CA1. Because of these fixes, Release 11.1(12)CA1 will be the minimum software release for new CT3IP orders. PROBLEMS: 1. Problems with packet error accounting. Ignores on the CT3IP were regularly being counted as overruns. Incorrect error accounting can lead to erroneous information on network status being provided to network operations personnel. 2. Packet handling errors: In lab tests Cisco engineers discovered a latent bug in the CT3IP that can result in abnormal packet handling under unusually severe operating conditions. While we are taking preemptive action to correct this bug, we do not expect this bug to manifest itself in operational networks. SOLUTION: We suggest that customers who are sensitive to error accounting accuracy or regularly run the CT3IP above 80 Kpps on average per direction, upgrade to Release 11.1(12)CA1, which is available on CCO. [CSCdj23299]

Wide-Area Networking

• It was found that the DRQ was becoming corrupted as a result of recursive invocation of drq_io (IPC packet passed to IPC code via dtq_consumer could result in a packet being returned via drq). drq_io was made safe for recursion. [CSCdj17845]

• With changes made for CSCdj17845 (recursive drq_io allowed), it became possible for QE to start work on a DRQ transfer entry, only to have the kernel code later change that entry. The solution is to write transfer the entry after all other data entries. [CSCdj24827]

Release 11.2(6)P Caveats/11.2(7)P Modifications

This section describes possibly unexpected behavior by Release 11.2(6)P. Unless otherwise noted, these caveats apply to all 11.2 P releases up to and including 11.2(6)P. For additional caveats applicable to Release 11.2(6)P, see the caveats sections for newer 11.2 P releases. The caveats for newer releases precede this section.

All the caveats listed in this section are resolved in Release 11.2(7)P.

Basic System Services

• Symptom--Under extremely heavy CPU interrupt states, a router with an FSIP, CT3, or any serial interface might experience the following "output stuck" error message:

%RSP-3-RESTART: interface Serial12/0/0:28, output stuck %RSP-3-RESTART: interface Serial12/0/0:6, output stuck %RSP-3-RESTART: interface Serial12/0/0:12, output stuck %RSP-3-RESTART: interface Serial12/0/0:2, output stuck

This is a result of a internal timer utility that can incorrectly return a false value under extreme interrupt situations, which causes the transmit buffers backing-store mechanism to falsely declare serial interface "output stuck."

Conditions--The symptom occurs on Cisco 7000 family routers using the CT3, 4- or 8-port FSIP cards, or any serial interface under Cisco IOS Release 11.1(10)CA, 11.1(11), and 11.2. It is only observed under oversubscribed traffic load conditions.

Workaround--Configure the interface to FIFO queueing using the no fair-queue command.

The command transmit-buffers backing-store is ON by default when an interface is configured for weighted fair-queueing. If the interface command no fair-queue is used, which changes the queueing strategy to FIFO, the transmit buffers backing-store is OFF by default. [CSCdj12815]

• A problem has been found in RSP code in Cisco IOS Release 11.2 P images. A failure condition can occur when backing-store or fair queuing are enabled. The conditions that could cause one of the above behaviors to occur are expected to be extremely rare.

For those customers running Release 11.2 P, we highly recommend upgrading all RSP-based systems to Cisco IOS Release 11.2(6)P or later. For those systems that cannot upgrade, this problem can be avoided by disabling both backing-store and fair queuing. See the instructions for this at the end of this message.

When packet load on RSP-equipped systems causes datagrams to be forwarded from SRAM to DRAM (a function of backing-store), 32 bytes of data may be randomly written into DRAM. This could result in several anomalous system behaviors including software-induced system crashes, dropped datagrams, and other anomalous errors.

Solution: For customers with Cisco IOS Release 11.2 P

Option 1: We highly recommend the installation of Release 11.2(6)P or later for 11.2(x)P images. This problem was fixed as bug CSCdi71609 in images 10.3 through 11.2. Unfortunately it was reintroduced as a result of merged code in Release 11.2 P only.

Option 2: Following are options to work around this bug. Disable backing-store and fair queuing on each interface with the following IOS commands:

no transmit-buffers backing-store
no fair-queue

Also disable udp-turbo flooding if the image is Release 11.0 or later. The Cisco IOS command to disable UDP turbo flooding is no ip forward-protocol turbo-flood, which is OFF by default in all releases.

However, it is important to look at the current configuration. An image configured before backing-store defaulted to OFF may have it ON for router interfaces. [CSCdj19231]

• This bug causes the connection setup to fail. If you enable crypto debug you will see the message cannot allocate blk. This problem happens after a connection has been renegotiate or reestablish about 50 or more times. [CSCdj20354]

Interfaces and Bridging

• An encapsulation change on a POS interface can result in a PCI timeout VIP reload. This is due to the POS interface accessing onboard registers before the onboard PLX chips are programmed. [CSCdj08510]

• The POS interface specific configuration commands pos specify-s1s0 and pos specify-c2 do not work correctly. [CSCdj09646]

• When there is another port adapter (for example, another FDDI FDX port adapter) in addition to the FDDI FDX port adapter in the same VIP2, the port adapter could (1) take a long time or forever to go into FDX operation, (2) after it goes into FDX operation, fall out of FDX mode for no good reason, or (3) see a lot of claims at the interface.

The workaround is to have the FDDI FDX port adapter only in one VIP2 and leave the other slot empty. [CSCdj11249]

• On a Cisco 7206 running Cisco IOS Release 11.1.10.4 CA1 when ipx route-cache is enabled on an interface, clients are unable to connect to Novell servers through the router. When ipx route-cach is disabled, they are able to connect. [CSCdj11354]

• The full-duplex command for the FDDI FDX port adapter is not recognized. The workaround is to use the old fddi full-duplex command instead. [CSCdj11501]

• In Cisco IOS Release 11.1(8)CA images and later, when transparent bridging is configured on a Cisco 7200 series router, a system reload can happen under heavy loads. The error message issued by the router indicates a bus error due to an illegal access to a low address. [CSCdj14850]

• Selecting line (recovered) clocking on the CT3's T1 channel 23 does not work. There is no known workaround, other then to not do it (that is, always use internal clocking on T1 channel 23). Depending on what equipment is at the remote end, this workaround might cause the remote end to slip.

This is fixed in CT3 firmware version 2.2.0. To determine your current CT3 firmware version, use the show cont t3 EXEC command:

CT3 H/W Version: 5, CT3 ROM Version: 1.2, CT3 F/W Version: 2.2.0 ^^^^^ 

You must have version 2.2.0 or greater to use line clocking on T1 channel 23. Other T1s are not affected. [CSCdj18588]

Release 11.2(5)P Caveats/11.2(6)P Modifications

This section describes possibly unexpected behavior by Release 11.2(5)P. Unless otherwise noted, these caveats apply to all 11.2 P releases up to and including 11.2(5)P. For additional caveats applicable to Release 11.2(5)P, see the caveats sections for newer 11.2 P releases. The caveats for newer releases precede this section.

All the caveats listed in this section are resolved in Release 11.2(6)P.

IP Routing Protocols

• On a Cisco 7500 RSP system, access list processing does not work with optimum switching. Packets that should be dropped are forwarded, and packets that should be forwarded are switched via the slower fast switching. The workaround is not to use optimum switching if access lists are defined. [CSCdj04279]

Novell IPX, XNS, and Apollo Domain

• IPX packets are getting corrupted with MIP and CT3 hardware with fast switching. The workaround is to disable ipx fastswitching on these interfaces. [CSCdj06068]

Wide-Area Networking

• In the presence of traffic on the ATM side (LANE configuration), if you reset the ATM module, then wait for the module to come on line and for the first spanning-tree ports (forwarding mode) to show up under the ATM port, then reset the ATM module, it fails to come on line and displays the following error message:

CDL-3W-1 (debug-eng) reset 4 Resetting module 4... CDL-3W-1 (debug-eng) Syndiags failed on Module Number 4 CDL-3W-1 (debug-eng) Wed Apr 2 1997, 16:37:48 Module 4 failed to come online.

At this point, the only workaround is to remove and install the ATM module.

The traffic pattern that caused this had to be "incrementing Destination Address" generated by an Ethernet sniffer.

This has been seen with NMP 2.1(705), ATM 3.2(3), and 3.2(2). This will be fixed in ATM 3.2(4). [CSCdj07474]

Release 11.2(4)P Caveats/11.2(5)P Modifications

This section describes possibly unexpected behavior by Release 11.2(4)P. Unless otherwise noted, these caveats apply to all 11.2 P releases up to and including 11.2(4)P. For additional caveats applicable to Release 11.2(4)P, see the caveats sections for newer 11.2 P releases. The caveats for newer releases precede this section.

All the caveats listed in this section are resolved in Release 11.2(5)P.

EXEC and Configuration Parser

• When you change the encapsulation on an interface from one that supports weighted fair queueing to one that does not and you make the change from the console or auxiliary port, there may be a memory loss of 8 KB each time you change the encapsulation. You can identify this problem by examining the output of the show memory allocating-process command, which shows that the number of memory blocks allocated by the EXEC software increases each time you change the encapsulation. If you do not change the encapsulation on an interface often, this problem should not have a significant impact on system performance. [CSCdi89723]

Release 11.2(3)P Caveats/11.2(4)P Modifications

This section describes possibly unexpected behavior by Release 11.2(3)P. Unless otherwise noted, these caveats apply to all 11.2 P releases up to and including 11.2(3)P. For additional caveats applicable to Release 11.2(3)P, see the caveats sections for newer 11.2 P releases. The caveats for newer releases precede this section.

All the caveats listed in this section are resolved in Release 11.2(4)P.

Interfaces and Bridging

• When pinging over synchronous DDR with HDLC Stacker compression, the router will unexpectedly reset. [CSCdi79832]

Release 11.2(1)P Caveats/11.2(3)P Modifications

This section describes possibly unexpected behavior by Release 11.2(1)P. Unless otherwise noted, these caveats apply to all 11.2 P releases up to and including 11.2(1)P. For additional caveats applicable to Release 11.2(1)P, see the caveats sections for newer 11.2 P releases. The caveats for newer releases precede this section.

All the caveats listed in this section are resolved in Release 11.2(3)P.

IBM Connectivity

• A hang of APPN's APPC stack (used to send locates and TDUs) can occur in rare situations when an outbound locate or TDU is in the process of being transmitted on a CP-CP session at the exact time that session is terminated (due to link failure or other reason). The APPC component does not handle this situation properly, and after the condition occurs, APPC and all locates and TDU processing becomes stuck. [CSCdi73085]

Cisco Connection Online

Cisco Connection Online (CCO) is Cisco Systems' primary, real-time support channel. Maintenance customers and partners can self-register on CCO to obtain additional information and services.

Available 24 hours a day, 7 days a week, CCO provides a wealth of standard and value-added services to Cisco's customers and business partners. CCO services include product information, product documentation, software updates, release notes, technical tips, the Bug Navigator, configuration notes, brochures, descriptions of service offerings, and download access to public and authorized files.

CCO serves a wide variety of users through two interfaces that are updated and enhanced simultaneously: a character-based version and a multimedia version that resides on the World Wide Web (WWW). The character-based CCO supports Zmodem, Kermit, Xmodem, FTP, and Internet e-mail, and it is excellent for quick access to information over lower bandwidths. The WWW version of CCO provides richly formatted documents with photographs, figures, graphics, and video, as well as hyperlinks to related information.

You can access CCO in the following ways:

• WWW:  http://www.cisco.com

• WWW:  http://www-europe.cisco.com

• WWW:  http://www-china.cisco.com

• Telnet:  cco.cisco.com

• Modem:  From North America, 408 526-8070; from Europe, 33 1 64 46 40 82. Use the following terminal settings: VT100 emulation; databits: 8; parity: none; stop bits: 1; and connection rates up to 28.8 kbps.

For a copy of CCO's Frequently Asked Questions (FAQ), contact cco-help@cisco.com. For additional information, contact cco-team@cisco.com.

Documentation CD-ROM

Cisco documentation and additional literature are available in a CD-ROM package, which ships with your product. The Documentation CD-ROM, a member of the Cisco Connection Family, is updated monthly. Therefore, it might be more up to date than printed documentation. To order additional copies of the Documentation CD-ROM, contact your local sales representative or call customer service. The CD-ROM package is available as a single package or as an annual subscription. You can also access Cisco documentation on the World Wide Web at http://www.cisco.com, http://www-china.cisco.com, or http://www-europe.cisco.com.

If you are reading Cisco product documentation on the World Wide Web, you can submit comments electronically. Click Feedback in the toolbar, select Documentation, and click Enter the feedback form. After you complete the form, click Submit to send it to Cisco. We appreciate your comments.