Table Of Contents
Release Notes for Cisco MWR 1900 Mobile Wireless Edge Router for Cisco IOS Release 12.2(8)MC2b
October 10, 2002
Cisco IOS Release 12.2(8)MC2b
These release notes are for the Cisco MWR 1900 Mobile Wireless Edge Router for Cisco IOS Release 12.2(8)MC2b. These release notes are updated as needed to describe new features, memory requirements, hardware support, software platform deferrals, and changes to the microcode and related documents.
For a list of the software caveats that apply to Cisco IOS Release 12.2(8)MC2b, see the "Caveats in Cisco IOS Release 12.2(8)MC2b" section.
To review the release notes for Cisco IOS Release 12.2, go to www.cisco.com and click Technical Documents. Select Release 12.2 from the Cisco IOS Software drop-down menu. Then click Cisco IOS Release Notes > Cisco IOS Release 12.2.
This document contains the following sections:
The Cisco MWR 1900 Mobile Wireless Edge Router running Cisco IOS Release 12.2(8) MC2 or a later Cisco IOS Release 12.2 MC is a networking platform optimized for use in mobile wireless networks. It extends IP connectivity to the cell site and Base Transceiver Station (BTS), and through a Fast Ethernet interface to the BTS, provides bandwidth-efficient IP transport of voice and data bearer traffic, as well as maintenance, control, and signalling traffic, over the leased line backhaul network between the BTS and leased line termination and aggregation node via compression (cRTP/cUDP) and packet multiplexing (PPPMux and MLPPP). It supports a limited set of interfaces and protocols, but offers high performance at a low cost while meeting the critical requirements for deployment in cell sites, including small size, extended operating temperature range, high availability, and DC input power flexibility.
System Configuration Requirements
The Cisco MWR 1900 Mobile Wireless edge router requires the following system configuration:
•Cisco IOS 12.2(8) MC2 or a later Cisco IOS Release 12.2 MC Software be installed.
•Network Time Protocol (NTP)
Network Time Protocol must be configured. The Cisco MWR 1900 router uses NTP to maintain a clocking source for the proper time stamping of system messages and log files.
When not using the Cisco MWR 1900 router in a redundant configuration, the standalone option must be configured from redundancy mode.
When using the Cisco MWR 1900 router in a redundant configuration, the keepalives under the FE must be set to 1.
Table 1 Memory Recommendations for the Cisco MWR 1900 Mobile Wireless Edge Router
Platform Software Image Flash
Cisco MWR 1900 Mobile Wireless Edge Router
32 MB Flash
128 MB DRAM
Determining the Software Version
To determine the version of Cisco IOS software running on your Cisco MWR 1900 router, log in to the Cisco MWR 1900 and enter the show version EXEC command:router> show versionCisco Internetwork Operating System SoftwareIOS (tm) 1900 Software (MWR1900-I-MZ), Version 12.2(8)MC2, EARLY DEPLOYMENT RELEASESOFTWARE (fc1)
Upgrading to a New Software Release
For general information about upgrading to a new software release, refer to Software Installation and Upgrade Procedures located at the following URL:
Upgrading to a New ROM Monitor Version
The MWR 1900 ROM Monitor (ROMMON) consists of two modules:
•A resident module that is not changed during the upgrade procedure.
•An upgradable module that is updated during the upgrade procedure. This is the only module that you will download from Cisco.com.
Note Before performing this procedure, you must download the new ROMMON image from Cisco.com. The download procedure is the same as downloading Cisco IOS software images.
Note In the event of a power outage, the ROM monitor download will not be successful.
To upgrade the ROMMON version on your Cisco MWR 1900 router, complete these steps from EXEC mode:
Step 1 Copy the new ROMMON image from a TFTP server to slot0.
Step 2 Verify that the new image has been copied:Router#dir slot0:Directory of slot0:/3 -rw- 871 Mar 01 1993 00:05:02 MWR1900-3-default.cfg4 -rw- 610704 Mar 01 1993 00:10:30 MWR1900_RM2.srec
Step 3 Upgrade the current configuration by entering the upgrade rom-monitor command as shown in the following example:Router# upgrade rom-monitor file slot0:MWR1900_RM2.srecWilma-2#upgrade rom-monitor file slot0:MWR1900_RM2.srec.122-8r.MC3This command will reload the router. Continue? [yes/no]:y
Step 4 Press Enter to continue. The router begins downloading the ROMMON image. The router automatically reboots.ROMMON image upgrade in progressErasing boot flasheeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeProgramming boot flash ppppNow ReloadingSystem Bootstrap, Version 12.2(20010915:181836) DEVELOPMENT SOFTWARECopyright (c) 1994-2001 by cisco Systems, Inc.Running new upgrade for first timeSystem Bootstrap, Version 12.2(8r)MC3, RELEASE SOFTWARE (fc1)TAC Support:http://www.cisco.com/tacCopyright (c) 2002 by cisco Systems, Inc.mwr1900 processor with 131072 Kbytes of main memoryMain memory is configured to 64 bit mode with parity disabledUpgrade ROMMON initializedrommon 1 >
New Features in the Cisco MWR 1900 Router with Cisco Release 12.2 MC Software
The software running on the Cisco MWR 1900 router consists of two components: Cisco IOS software running on the MIPs-based route processor portion of the router hardware, and microcode running on the Cisco network processor, also known as Parallel eXpress Forwarding (PXF). Because the Cisco MWR 1900 router is designed specifically for use in an IP-RAN in the BTS, it is customized for performance, high-availability, quality of service, and link efficiency.
For detailed descriptions of each of these features, see the Cisco MWR 1900 Mobile Wireless Edge Router Software Configuration Guide.
•Cisco IOS Software Features
Cisco IOS software function added for the Cisco MWR 1900 router IP-RAN application include:
Standard Cisco IOS software features supported in this release include:
–MLP, PPP Control Path (IPCP, NCP, LCP, CLNS)
•Network Processor Software
The following features are supported in the network processor:
–MLP, PPP Data Path (MLP LFI is not supported)
•Cisco Hot Standby Router Protocol (HSRP) support
Limitations, Restrictions, and Important Notes
Caution The Cisco MWR 1900 router does not support online insertion and removal (OIR) of WAN interface cards. Any attempt to perform OIR on a card in a powered up router might cause damage to the card.
Caution Removing the compact flash from the Cisco MWR 1900 router during a read/write operation might corrupt the contents of the compact flash, rendering it useless. To recover from an accidental removal of or corruption to the compact flash, a maintenance spare with the appropriate bootable Cisco IOS software image might be needed.
Unsupported Cisco IOS Software Features
The Cisco MWR 1900 router requires a special version of Cisco IOS software. Not all Cisco IOS software features can be used with the Cisco MWR 1900 router as the core routing is handled by the network processor. The following standard Cisco IOS software features are not supported on the Cisco MWR 1900 router:
•Security Access Control Lists
•Frame Relay (FR)
Upgrading the VWIC-2MFT-T1-DIR Microcode
When upgrading the image on your Cisco MWR 1900 router, power cycle the router or perform a microcode reload on the VWIC-2MFT-T1-DIR to ensure that the firmware for the VWIC-2MFT-T1-DIR is updated during the upgrade.
Disabling PPP Multiplexing
To fully disable PPP multiplexing (PPPMux), issue the no ppp mux command on the T1 interfaces of the routers at both ends of the T1 link. If PPP multiplexing remains configured on one side of the link, that side will offer to receive PPP multiplexed packets.
MLP LFI Support
MLP LFI is not supported by the Cisco MWR 1900 router. Therefore, MLP LFI must be disabled on peer devices connecting to the Cisco MWR 1900 router T1 MLP connections.
Caveats in Cisco IOS Release 12.2(8)MC2b
The following sections list and describe the open, resolved, unreproduced, and closed caveats for the Cisco MWR 1900 router running Cisco IOS Release 12.2(8)MC2b. Only severity 1 through 3 caveats are included.
Caveats describe unexpected behavior in Cisco IOS software releases. Severity 1 caveats are the most serious caveats, severity 2 caveats are less serious, and severity 3 caveats are the least serious of these three severity levels.
Caveats in Cisco IOS Releases 12.2 and 12.2 T are also in Cisco IOS Release 12.2(8)MC2b. For information on caveats in Cisco IOS Release 12.2, see Caveats for Cisco IOS Release 12.2. For information on caveats in Cisco IOS Release 12.2 T, see Caveats for Cisco IOS Release 12.2 T. These two documents list severity 1 and 2 caveats and are located on CCO and the Documentation CD-ROM.
Note If you have an account with Cisco.com, you can use Bug Navigator II to find caveats of any severity for any release. To reach Bug Navigator II, Login to Cisco.com and click Software Center: Cisco IOS Software: Cisco Bugtool Navigator II. Another option is to go directly to http://www.cisco.com/support/bugtools.
The caveats listed in this section are open in Release 12.2(8)MC2b.
When using an extended ACL with the access-group command to define traffic using the class policy-map configuration command, the Cisco MWR 1900 router crashes to ROMmon. This condition happens because extended ACLs are currently not supported.
Workaround: The access-group command is not part of the IP-RAN configuration. However, if using the command, use only with standard ACLs.
When traffic shaping is applied to an MLP output interface, the shaped output rate might be slightly higher than that defined. This condition occurs because the data rate to that interface is greater than the shaping rate.
Workaround: There is currently no workaround.
When the class-default queue is used with other class-based queues, the class-default queue's committed information rate (CIR) and the excess information rate are not configured correctly.
Workaround: Manually configure the committed information rate using the shape class-map configuration command. The excess information rate cannot be manually configured, therefore, there is no workaround for it not configuring correctly.
QoS class-based WFQs configured with a low percentage of bandwidth are unable to use the unused bandwidth from queues assigned a high percentage of the bandwidth.
Workaround: Deconfigure QoS on the output interface.
The caveat listed in this section is closed in Release 12.2(8)MC2b.
When PPP multiplexing and RTP compression are enabled, some inbound cUDP packets might be dropped when there are only a small number of active cUDP flows and the per flow data rate is above 250 packets per second.
The caveat listed in this section has not been reproduced during testing. In the unlikely event you experience the problem described in this section, contact Cisco customer service.
An MLP bundle might occasionally have a few inactive links. This condition causes the bandwidth of the multilink bundle to be incorrect for the number of T1 interfaces configured. This condition occurs when one or more T1 links of an MLP bundle have their encapsulation changed to PPP (Encapsulation Type 5) instead of MLP (Encapsulation type 12).
This section lists the caveats resolved in Release 12.2(8)MC2b. It also lists those caveats that represent feature enhancements in Release 12.2(8)MC2b.
Following a switchover from standby mode to active mode, the traffic latency through the newly active router might be slower. Also, the statistics displayed when the show ppp multilink command is issued indicate lost fragments.
When the PXF attempts to restart after reloading microcode, the MWR 1900 might crash after a Toaster processor exception error occurs.
After a MWR 1900 reload, the router drops cUDP packets. Use the show ip rtp header-compression command to view the increasing packet loss on the MWR 1900 router.
When the MWR 1900 is reparenting from one multilink bundle to another, for example, multilink1 to multilink2, the reparenting process works without problem. However, when reparenting in the reverse order (from multilink2 to multilink1), when multilink1 becomes active, multilink2 hangs.
When a T1 failure occurs, traffic recovers over the MLP link within 6 seconds.
This caveat is a feature enhancement to the keepalive interface configuration command. With this enhancement, you can also configure a maximum number of retries before a link is declared down by issuing the command as follows:
keepalive [interval] [retries]
–interval is the keepalive interval (in seconds). Valid value is a number greater than 0. The default is 10.
–retries is the number of times a link will be tried again before being declared down. Valid value is a number between 1 and 255. The default is 5.
For implementation in an IP RAN solution, the recommended configuration is as follows:
On the MWR 1900:interface Serial0/0:0no ip addressencapsulation pppkeepalive 1 2no cdp enableppp multilinkmultilink-group 1end
On the MGX-RPM-1FE-CP back card;interface Virtual-Template2bandwidth 1536no ip addresskeepalive 1 2no peer default ip addressppp multilinkmultilink-group 101end.
Note In the MGX-RPM-1RE-CP backcard configuration example, only the keepalive interface command and configuration recommendation is specific to implementation in an IP RAN solution.
Collecting Data for Router Issues
To collect data for reporting router issues, issue the following command:
•show tech-support—Displays general information about the router when it reports a problem.
Collecting Data for Redundancy Issues
To collect data for redundancy-related issues, issue the following commands while in EXEC mode:
•show redundancy—Displays current or historical status and related information on redundant Dial Shelf Controllers (DSCs).
•show controllers—Displays information that is specific to the hardware.
•show standby—Displays Hot Standby Router Protocol (HSRP) information.
•show ip interface—Displays the usability status of interfaces configured for IP.
Collecting Data for ROMmon Issues
To collect data for ROMmon issues, issue the following command while in EXEC mode:
•showmon— Displays currently selected ROM monitor.
Collecting Data for Router Rebooting to ROMmon
If a router reboot to ROMmon occurs, issue the dir device ID command where device ID is slot0:, and look for the router processor or network processor exception file (crashinfo* or pxf_crashinfo* respectively). Once you have located one of these files, you can email the file along with a description of the problem to your Cisco representative.
This section contains information that was not included or was documented incorrectly in the Cisco MWR 1900 Software Configuration Guide. The heading in this section corresponds with the applicable section title in the documentation.
Configuring RTP/UDP Compression
The maximum number of RTP header compression connections per MLP bundle is documented as 600 when in fact, up to 1000 connections are supported on an interface. This amendment also applies to the ip rtp header-compression command description.
The show ip rtp header-compression Command
The detail keyword is not supported in the show ip rtp header-compression command. Therefore, output does not display for the detail keyword if specified in command.
The following sections describe the documentation available for the Cisco MWR 1900 Mobile Wireless Edge Router. These documents consist of hardware and software installation guides, Cisco IOS configuration guides and command references, system error messages, and other documents.
Documentation is available as printed manuals or electronic documents.
These documents are available for the Cisco MWR 1900 Mobile Wireless Edge Router on Cisco.com and the Documentation CD-ROM:
•Cisco MWR 1900 Mobile Wireless Edge Router
–Cisco MWR 1900 Hardware Installation Guide
–Cisco MWR 1900 Software Configuration Guide
–Cisco MWR 1900 Rack Mounting Instructions
–Cisco MWR 1900 Regulatory Compliance and Safety Information
•VWIC-2MFT-T1-DIR, VWIC-2MFT-E1-DIR Installation Instructions
•MGX-RPM-1FE-CP Back Card Installation and Configuration Note
On Cisco.com at:
Technical Documents: Cisco Product Documentation: Fixed and Mobile Wireless Solution: Cisco Mobile Wireless IP-RAN: Cisco Mobile Wireless IP-RAN Version 1.0
On the Documentation CD-ROM at:
Cisco Product Documentation: Fixed and Mobile Wireless Solution: Cisco Mobile Wireless IP-RAN: Cisco Mobile Wireless IP-RAN Version 1.0
Feature modules describe new features supported by Cisco IOS Release 12.2 MC and are updates to the Cisco IOS documentation set. A feature module consists of an overview of the feature, configuration tasks, and a command reference.
On Cisco.com at:
Technical Documents: Cisco IOS Software: Cisco IOS Release 12.2: New Feature Documentation: New Features in 12.2-Based Limited Lifetime Releases: New Features in Release 12.2 MC: New Features in Release 12.2 MC2
On the Documentation CD-ROM at:
Cisco Product Documentation: Cisco IOS Software Configuration: Cisco IOS Release 12.2: New Feature Documentation: New Features in 12.2-Based Limited Lifetime Releases: New Features in Release 12.2 MC: New Features in Release 12.2 MC2
These sections explain how to obtain documentation from Cisco Systems.
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Obtaining Technical Assistance
Cisco provides Cisco.com as a starting point for all technical assistance. Customers and partners can obtain online documentation, troubleshooting tips, and sample configurations from online tools by using the Cisco Technical Assistance Center (TAC) Web Site. Cisco.com registered users have complete access to the technical support resources on the Cisco TAC Web Site.
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Technical Assistance Center
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•Priority level 2 (P2)—Your production network is severely degraded, affecting significant aspects of business operations. No workaround is available.
•Priority level 1 (P1)—Your production network is down, and a critical impact to business operations will occur if service is not restored quickly. No workaround is available.
The Cisco TAC resource that you choose is based on the priority of the problem and the conditions of service contracts, when applicable.
Cisco TAC Web Site
You can use the Cisco TAC Web Site to resolve P3 and P4 issues yourself, saving both cost and time. The site provides around-the-clock access to online tools, knowledge bases, and software. To access the Cisco TAC Web Site, go to this URL:
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If you are a Cisco.com registered user, and you cannot resolve your technical issues by using the Cisco TAC Web Site, you can open a case online by using the TAC Case Open tool at this URL:
If you have Internet access, we recommend that you open P3 and P4 cases through the Cisco TAC Web Site.
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.
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