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Table Of Contents

Release Notes for Cisco IOS Release 12.2(10)DA1 for Cisco DSLAMs with NI-2

Contents

System Requirements

New and Changed Information

Cisco IOS Release 12.2(10)DA1

New Hardware Features in Release 12.2(10)DA

New Software Features in Release 12.2(10)DA

Installation Notes

Update the Image in Bootflash to the 12.2(10)DA1 dboot Image

Upgrade the Bootflash Image on the NI-2 Card to the 12.1(5)DA1 dboot Image

Limitations and Restrictions

Attainable Bit Rate Is Conservative on 4xflexi-DMT and 8xDMT

CPE Performance Issues with Overhead Framing Modes 0, 1 and 2

Trellis Coding Enable Default Recommendations

Restrictions on NI-2 IP Services

Frame Relay PVCs/Soft PVCs on an IDSL Interface

Use of a Ring Topology in a DSLAM Subtend Environment to Achieve ATM Trunk Redundancy

Cisco DSL Manager

Important Notes

Line Card Features

NI-2 IP Services

Soft PVC Address Changes upon Upgrade from Release 12.1(4)DA or Earlier

Configuring Cisco Routers for Use with IDSL

Assigning VPI Values to Shaped VP Tunnels

Installing Multiple Cisco 6160 Chassis in an Equipment Rack

Console Logging

Caveats

Resolved Caveats—Release 12.2(10)DA1

Open Caveats—Release 12.2(10)DA

Open Caveats—Release 12.2(7)DA

Open Caveats—Release 12.2(5)DA

Closed Caveats—Release 12.2(5)DA

Open Caveats—Release 12.2(1b)DA

Resolved Caveats—Release 12.2(10)DA

Resolved Caveats—Release 12.2(7)DA

Resolved Caveats—Release 12.2(5)DA

Resolved Caveats—Release 12.2(1b)DA

Related Documentation

Hardware Documentation

Software Documentation

Obtaining Documentation

World Wide Web

Documentation CD-ROM

Documentation Feedback

Obtaining Technical Assistance

Cisco.com

Technical Assistance Center


Release Notes for Cisco IOS Release 12.2(10)DA1 for Cisco DSLAMs with NI-2


November 3, 2006

These release notes describe features and caveats in Cisco IOS Release 12.2(10)DA1 for the Cisco 6015, Cisco 6160, and Cisco 6260 digital subscriber line access multiplexers (DSLAMs).


Note When you upgrade from Cisco IOS 12.1(5)DA1 or earlier images on the NI-2 card to Release 12.2(10)DA1, you must format the bootflash on the NI-2 card before loading the 12.2(10)DA1 dboot image. See the "Update the Image in Bootflash to the 12.2(10)DA1 dboot Image" section.


For pointers to more information about the Cisco 6015, Cisco 6160, Cisco 6260, and their software, refer to the "Related Documentation" section. To learn more about caveats, visit the Cisco web site—see the "Obtaining Documentation" section for details. Information about electronic documentation can be found in both the "Obtaining Documentation" section and the "Documentation CD-ROM" section.

Contents

This document contains the following topics:

System Requirements

New and Changed Information

Installation Notes

Limitations and Restrictions

Important Notes

Caveats

Related Documentation

Obtaining Documentation

Obtaining Technical Assistance

System Requirements

Cisco IOS Release 12.2(10)DA1 runs on these DSLAM systems:

Cisco 6015

Cisco 6160

Cisco 6260

New and Changed Information

The following sections provide new and changed information for Cisco IOS Release 12.2(10)DA1 and Release 12.2(10)DA.

Cisco IOS Release 12.2(10)DA1

Cisco IOS Release 12.2(10)DA1 is based on Cisco IOS Release 12.2(10)DA and includes all of the new features introduced in that release. In addition, this release fixes the bugs described in the"Resolved Caveats—Release 12.2(10)DA1" section.

New Hardware Features in Release 12.2(10)DA

No new hardware features were introduced in Cisco IOS Release 12.2(10)DA.

New Software Features in Release 12.2(10)DA

The following new software features were introduced in Cisco IOS Release 12.2(10)DA.

DMT Power-Management-Additional-Margin

The 8xDMT line card can run in power-management mode in the G.dmt or the T1.413 mode. The resulting power cutback produces a reduction in power dissipation and crosstalk. Only 8xDMT line cards support power management. All CPE may not support the DSL functionality for power management to function correctly. Check with a Cisco customer representative to verify CPE compatibility with the 8xDMT power management.

You control the Power Management feature by issuing a dmt power-management-additional-margin command inside a profile and assigning that profile to a line card interface. This IOS command allows you to set the additional margin for each channel from 0 dB (off) to 15 dB. This sets the additional margin that will be added to the target margin. If the sum of the target margin and additional margin exceeds 15dB, it is capped at 15dB. If the actual margin of the line is higher than the sum of the configured target and additional margin, and all the above conditions are met, then power management attempts to reduce the actual margin, and as a consequence the power level as well.

Not all CPE support power management. If you connect an unsupported CPE to a port on which power management is turned on, you will not see a reduction in the actual margin or power level. The operating modes supported by power management are T1.413and g-992-1 (G.DMT). Table 1 shows the CPE and specifies which operating mode supports them.

Table 1 CPEs and Power Management Support 

CPE
G.DMT
T1.413

Cisco 677

not supported

not supported

Cisco 678

not supported

supported

Cisco SOHO 77/Cisco 827

supported

supported

ADSL WAN Interface Card (WIC)

supported

supported

Alcatel chipset based modem

supported

supported


A reduction in the power level occurs if there is excess margin on the line. For the downstream direction, if there is excess margin, then IOS displays a reduction in margin for the modes listed above, and a reduction in transmit power for T1.413 mode. For the upstream direction, if there is excess margin, then IOS displays a reduction in the margin for g-992-1 mode only. IOS will not display a reduction in transmit power for the upstream direction.

ATM OAM Cells Supported in Fast Path Mode

The NI-2 now supports atm oam cells through fast path mode. Also, you can now use the ping atm utility command in fast path mode.

Enhanced ATM OAM Segment Cells Support

A new command, atm oam intercept segment, allows you to enable or disable receiving atm oam segment cells on valid connections. By default, the atm oam cells received on unconfigured or down connections are dropped. For more information, see the Command Reference for Cisco DSLAMs with NI-2.

MIB Object Changes

This release contains changes to the following Management Information Base (MIB) objects:

The power management feature is configurable via the CISCO-ADSL-DMT-LINE-MIB. The mib object cAdslAtucDmtConfPMAddSnrMgn configures the downstream component and the mib object cAdslAturDmtConfPMAddSnrMgn configures the upstream component on that particular dsl profile. Both objects default to 0 and can be configured from 0 to 150 tenths of dBs in increments of 10. Setting the objects to 0 explicitly via SNMP will disable the power management feature on the ports.

Installation Notes

Update the Image in Bootflash to the 12.2(10)DA1 dboot Image

When you upgrade from Cisco IOS Release 12.1(5)DA1 or earlier images on the NI-2 card to Release 12.2(10)DA1, you must reformat the bootflash on the NI-2 card.


Note If you are upgrading from Cisco IOS Release 12.1(6)DA, 12.1(6)DA2, 12.1(7)DA, 12.1(7)DA2, 12.1(7)DA3, 12.2(1b)DA, 12.2(1b)DA1, 12.2(5)DA, 12.2(5)DA1, 12.2(7)DA, or 12.2(10)DA you do not need to reformat the bootflash. You can skip this section and follow the DSLAM upgrade procedure at the following URL:
http://www.cisco.com/univercd/cc/td/doc/product/dsl_prod/ios_dsl/rel122/config/04conf09.htm.



Note We highly recommend that you have console access to the NI-2 card during the upgrade procedure. You can use the console connection to troubleshoot any unexpected events that occur during the upgrade.


To update the boot image, perform the following steps in privileged EXEC mode:

 
Command
Purpose

Step 1 

DSLAM# dir bootflash:

Verify that the bootflash image is ni2-dboot-mz.121-5.da1 or ni2-dboot-mz.121-4.da. If it is neither, go to the "Upgrade the Bootflash Image on the NI-2 Card to the 12.1(5)DA1 dboot Image" section and perform the instructions there, and then return to this step. This is required because of a problem (CSCdr89374) in old bootflash images.

Step 2 

DSLAM# dir flash:

Display the name of the Flash file that begins ni2- and use it as filename in Step 3.

Step 3 

DSLAM# delete flash:filename

Delete the Flash file name found in Step 2. Repeat Step 2 and Step 3 until all files in the Flash file have been deleted.

Step 4 

DSLAM# squeeze flash:

Recover available space in Flash memory.

Step 5 

DSLAM# copy tftp://tftpserver:TFTPBOOT/ni2 -dsl-mz.122-10.da1 flash:

Copy the Cisco IOS image from a TFTP server to Flash.

Step 6 

DSLAM# configure terminal

DSLAM (config)# no boot system

DSLAM (config)# boot system flash:ni2-dsl-mz.122-10.da1

DSLAM# end

Enter global configuration mode.

Disable the boot from system.

Specify the name of the system image to load at startup.

End global configuration mode.

Step 7 

DSLAM# copy running-config startup-config

Save your changes to the startup configuration.

Step 8 

DSLAM# reload

Reload the system to upgrade the image.

Step 9 

DSLAM# show version

Confirm that the running image is ni2-dsl-mz.122-10.da1. If it is not, go to Step 5.

Step 10 

DSLAM# format bootflash:

Erase all information in bootflash memory. Answer y to all confirm questions. When the DSLAM returns you to the EXEC prompt, bootflash memory is successfully formatted and ready for use.

Ensure that the bootflash is 3.8 MB total. If it is not, go to Step 5.

Step 11 

DSLAM# copy tftp://tftpserver:TFTPBOOT/ni2 -dboot-mz.122-10.da1 bootflash:

Copy the boot image from a TFTP server to the bootflash.

Step 12 

DSLAM# reload

Reload the system to upgrade the image.

Upgrade the Bootflash Image on the NI-2 Card to the 12.1(5)DA1 dboot Image

When you upgrade from Release 12.1(3)DA or earlier images on the NI-2 card to Release 12.1(5)DA1, we recommend that you upgrade the bootflash image on the NI-2 card to the 12.1(5)DA1 dboot image.

To upgrade the dboot image in bootflash, perform the following steps:

 
Command
Purpose

Step 1 

DSLAM> enable

Password: <password>

DSLAM#

Enter enable mode.

Enter the password.

You have entered enable mode when the prompt changes to DSLAM#.

Step 2 

DSLAM# delete bootflash:filename

Make room in the bootflash by deleting the name of the current boot image.

Step 3 

DSLAM# squeeze bootflash

Recover available space in bootflash using the squeeze bootflash command.

Step 4 

DSLAM# copy tftp://[server name] /[directory]/ni2-dboot-mz.121-5.da1 bootflash:

Copy the boot image to the bootflash.

Step 5 

DSLAM# show version

Record the current value of the config-register that appears on the last line of the show version display.

Step 6 

DSLAM# configure terminal

Enter global configuration mode. You have entered global configuration mode when the prompt changes to DSLAM(config)#.

Step 7 

DSLAM(config)# config-register 0

Set the config register to 0x0000 so that the NI-2 reboots in the ROM monitor.

Step 8 

DSLAM(config)# exit

Exit global configuration mode.

Step 9 

DSLAM# copy running-config startup-config

Save the running configuration.

Step 10 

DSLAM# reload

Reset the system.

Step 11 

rommon> set

If you see BOOTLDR after you enter this command, the image in bootflash is already being used as the bootstrap image; go to Step 15. Otherwise, go to Step 12 and enter the commands in Steps 12 through 14 to force the system to use ni2-dboot-mz.121-5.bin as the bootstrap image.

Step 12 

rommon> unset BOOTLDR

Unset BOOTLDR to remove the variable.

Step 13 

rommon> sync

Sync to save the state of rommon.

Step 14 

rommon> b

When the NI-2 boots, it uses ni2-dboot-mz.121-5da.bin as the bootstrap image.

Step 15 

DSLAM# configure terminal

Enter global configuration mode. You have entered global configuration mode when the prompt changes to DSLAM(config)#.

Step 16 

DSLAM(config)# config-register value

Set the config-register to the value you recorded in Step 5.

Step 17 

DSLAM(config)# exit

Return to enable mode.

Go to the "Update the Image in Bootflash to the 12.2(10)DA1 dboot Image" section.

Limitations and Restrictions

This section describes the limitations and restrictions for Cisco IOS DSLAM releases.

Attainable Bit Rate Is Conservative on 4xflexi-DMT and 8xDMT

The reported DMT aggregate bit rate is less than the true attainable bit rate.

Limitations

Due to line condition variations between trains, the effect of trellis coding, interleave delay, FEC check bytes, and so forth, the attainable bit rate estimate is not always 100 percent accurate. A conservative approach was taken in making the estimate; therefore, in general, you can get a higher rate than what the estimate suggests. For a fast-path scenario, the results should track fairly closely for the downstream rate and err on the conservative side for the upstream rate. For an interleave path scenario, the results are highly dependent on configurations.

At a higher reach or where line conditions are not optimal, the effect of having trellis coding, interleave delay, and FEC check bytes can provide a much higher rate than was estimated (greater than 128 kbps).

Workaround

There is no workaround. The aggregate bit rate calculation is an estimate, which does not accurately model all of the line conditions that affect the true attainable bit rate for a given profile. The calculations for aggregate bit rate are performed as follows:

The downstream capacity is obtained from the number of Reed-Solomon payload bytes per frame exchanged during line training, that is, the K value. The per-second estimate is then calculated from this K value. An extrapolated margin value is derived from the per-second estimate to make sure that if the line is trained at the estimated rate, it will still have an adequate margin.

For upstream, unlike downstream, the Reed-Solomon payload bytes per frame is not readily available. Furthermore, unlike downstream, which requires a CPE EOC response to know the downstream margin, the upstream margin is readily available at the CO (upstream margin is measured at the CO end). Using this upstream margin and the number of bins utilized for upstream, an estimate of upstream attainable bit rate is made. (The associated DDTS numbers are CSCdv05351 and CSCdv05322.)

CPE Performance Issues with Overhead Framing Modes 0, 1 and 2

The customer premises equipment (CPE) does not train or perform reliably when the Discrete Multitone (DMT) profile is set to use overhead framing mode 0, 1, or 2.

Overhead framing modes 0, 1, and 2 are not supported at this time.

Workaround

Overhead framing mode 3 is designed for use in Asynchronous Transfer Mode (ATM). While overhead framing mode 1, which is not currently supported, is designed for Synchronous Transport Module (STM) mode. Configure your profiles to use overhead framing mode 3. Overhead framing mode 3 uses only 32 bytes of administrative overhead. Compared with overhead framing mode 1, it allows more bandwidth to be allocated to user data.

Trellis Coding Enable Default Recommendations

Trellis coding is disabled by default on the NI-2 because it is not supported on the 4xDMT (ATUC-1-4DM) card. However, trellis coding is supported on the 4xFlexiDMT (ATUC-4FLEXIDMT) and 8xDMT (ATUC-1-DMT8) line cards. Additionally, trellis coding should be enabled for the 4xFlexiDMT and 8xDMT line cards.

For all 4xDMT (ATUC-1-4DMT) ports in the DSLAM, make sure that trellis coding is disabled in the dsl-profile for those ports. For all 4xFlexiDMT and 8xDMT ports in the DSLAM, make sure that trellis coding is enabled except with ADI chipset based CPE using ADI F/W prior to ADI 3.1. This includes all Cisco 677 and Cisco 627 CPEs.

See the documentation at the following location for details on the commands used to change trellis coding settings on the NI-2:

http://www.cisco.com/univercd/cc/td/doc/product/dsl_prod/ios_dsl/rel122/config/04conf04.htm#xtocid1734531

Restrictions on NI-2 IP Services

This section describes restrictions on Cisco NI-2 IP services.

Restricted Layer 3 Services

Cisco IOS Release 12.2(10)DA does not support the following Layer 3 services (or else these services are limited, as noted):

IP Quality of Service.

IP Queueing.

IP Multicast.

L2TP Tunnel Priority and Limit sessions.

L2TP Network Server (LNS).

The maximum number of MPLS/VPN for PPPoA terminations is 25 VPNs for PPPoA and 1 VPN for PPPoE.

We recommend use of a virtual template for PPPoX termination rather than a dialer interface.

MPLS LDP protocol is not supported in this release. Use TDP protocol.

Up to 32 subinterfaces can be used for IP termination under the trunk or subtend ports.

Each DSLAM can support up to 50 MPLS VPNs.

Integrated Routing and Bridging Not Supported

MPLS VPN mapping of RFC 1483 routed sessions must not be confused with Integrated Routing and Bridging (IRB). IRB is not supported by MPLS VPN mapping of RFC 1483 routed sessions.

VPN Interfaces Restricted to Trunk Interfaces

Do not configure subtended interfaces for MPLS VPN services. Only trunk interfaces support MPLS VPN mapping of RFC 1483 routed sessions.

MPLS ATM-Label Switch Router Functionality Not Supported

DSLAMs are not meant for use as MPLS ATM-Label Switch Routers (ATM-LSRs). When designing your network, keep in mind that DSLAMs act only as Label Edge Routers (LERs).

Performance Restrictions for MPLS VPN Traffic

MPLS VPN-enabled interfaces do not perform as well as switched VCs. Please take this into consideration when deploying MPLS VPNs in your networks.

Restricted MPLS Features

The following MPLS-related features are not part of MPLS VPN mapping of RFC 1483 routed sessions:

MPLS traffic engineering

MPLS multicast

DSL Interface Limitations

In DSLAMs, each DSL interface can support multiple permanent virtual circuits (PVCs), but we recommend that you use one routed MPLS VC if a dynamic routing protocol, such as RIP, is used between the CE and the PE.

MPLS VPN Mapping Not Supported on the Eight-Port IDSL ITU-C Line Card

Routed termination of IDSL connections is not supported since Cisco IOS Release 12.2(1b)DA.

Frame Relay PVCs/Soft PVCs on an IDSL Interface

The number of Frame Relay PVCs/Soft PVCs on an IDSL interface is restricted to 1 if you use the default row in a frame-relay connection traffic table (FR-CTT).

When upgrading to Release 12.2(10)DA1 from previous releases, you must first create a new row in the FR-CTT with the desired CIR value and use the resultant row number during PVC/Soft PVC creation. If you do not create a new row, the second FR PVC/Soft PVC command is not parsed and installed on the IDSL interface.

Use of a Ring Topology in a DSLAM Subtend Environment to Achieve ATM Trunk Redundancy

Ring topology is achieved when a node in the subtend tree is attached to the ATM access to provide a physically redundant loop. Thus, when the primary ATM access or one of the ATM trunks in the subtend tree fails, the soft permanent virtual circuits (SPVCs) can be dynamically rerouted through the use of Private Network-Network Interface (PNNI). See Figure 1.

Figure 1 SPVCs Prior to Failure

This redundancy requires the use of SPVCs. If you use permanent virtual circuits (PVCs) or permanent virtual paths (PVPs), redundancy cannot be provided. The use of the SPVCs allows traffic to be rerouted around the failed access point, because SPVCs leverage this feature of PNNI. When the failure occurs, the SPVCs are disconnected and dynamically reconnected across the new path. See Figure 2.

Figure 2 SPVCs Dynamically Rerouted

Requirements

If you implement ring topology in a DSLAM subtend to achieve ATM trunk redundancy, the following requirements apply:

You must use SPVCs, PNNI, ATM signaling, and Interim Local Management Interface (ILMI) to enable rerouting. PNNI, ATM signaling, and ILMI are enabled by default. Permanent connections such as PVCs and shaped virtual paths (VPs) do not benefit from the redundant link.

You must make the redundant link's PNNI administrative weight higher than the PNNI weight of the primary trunk. Once you change the weight of the redundant link, the subtend tree uses this link only if a failure occurs.

Limitations

When the redundant link is active, the following occurrences are problems:

Loss of subtending fairness.

Increase in latency as well as an increase in cell delay variation (CDV) between the cells. Delay-sensitive traffic, such as voice and video, or traffic that is susceptible to jitter, such as constant bit rate (CBR) voice, might be compromised. This technique is best realized for unspecified bit rate (UBR) traffic, such as consumer internet access, where no strict quality of service (QoS) objectives are required.

Once the redundant link is active, the following occurrences are potential problems:

Greater possibility of increased congestion in the DSLAM ATM switch fabric, which might cause loss of data.

When the main link is restored, there is downtime while the path is being rerouted. After the SPVCs are rerouted to the redundant ATM trunk and the original trunk is repaired or brought back into service, you must manually intervene. You must flap (shut/noshut) the subtend port. Because of retries on the current path, you must keep the trunk down until the maximum retry interval expires.

Cisco DSL Manager

If you are using versions of Cisco DSL Manager (CDM) before CDM Release 3.4—from CDM Release 1.0 to CDM Release 3.3(3)—do not upgrade the DSLAMs to this new Cisco IOS release.

If you use both the CDM network management application and the Cisco IOS command line interface to manage your Cisco DSLAMs, you should be aware of certain configuration and procedural implications. Please refer to the Release Notes for the Cisco DSL Manager, Release 3.4 for this information.

Important Notes

This section provides important information about Cisco IOS DSLAM releases.

Line Card Features

Table 2 shows which line card features are available on the 4xDMT, 4xFlexi, and 8xDMT line cards.

Table 2 Line Card Features

Feature
4xDMT
4xFlexi
8xDMT

Interleave

yes

yes

yes

Fastpath

no

yes

yes

Min rate blocking

alarm only

yes

yes

SNR margin

alarm only

alarm and retrain capable

alarm and retrain capable

Trellis encoding

no

yes

Disable on ADI based CPE.

yes

Ignores profile setting. The line card firmware automatically controls trellis encoding based on the CPE type.

Overhead framing

Mode 0,1,2,3 with ADI based CPE

Mode 3 is recommended with other CPE.

Mode 3 only

Mode 3 only

Power Management Additional Margin

no

no

T1.413
G.DMT

Operating mode

T1.413
G.DMT
G.Lite
Auto

T1.413
G.DMT
G.Lite
Auto

T1.413
G.DMT
G.Lite
Auto

Training mode

Quick recommended

No affect

No affect

677 CPE support

yes

yes

yes

678 CPE support

no

yes

yes

Alcatel-based CPE

limited performance

yes

yes

NI-2 IP Services

During system startup, the following protocol warning messages display. You can ignore these messages.

If RADIUS is configured:

%AAAA-4-SERVUNDEF: The server-group "radius" is not defined. Please define it.

If VPN is configured:

% Can't create VRF

Soft PVC Address Changes upon Upgrade from Release 12.1(4)DA or Earlier

When you upgrade from Cisco IOS Release 12.1(4)DA or earlier to Release 12.2(10)DA1, the default soft PVC addresses on all interfaces change. This occurs only when you upgrade to Release 12.2(10)DA1 from Release 12.1(4)DA or earlier.

Workarounds:

Reconfigure the soft PVCs associated with all interfaces.

Assign a (nondefault) address to the interfaces.

Configuring Cisco Routers for Use with IDSL

If you wish to use a Cisco router for an IDSL application and the router is running a Cisco IOS release prior to Release 12.1, you must configure the ISDN switch type. If you do not configure the ISDN switch type on the Cisco router, the router's BRI interface might not come back up after the IDSL line goes down and comes back up.

To prevent this problem from occurring, execute the isdn switch-type basic-ni command in global configuration mode on the router.

This problem does not occur if the Cisco router is running Cisco IOS Release 12.1 or later.

Assigning VPI Values to Shaped VP Tunnels

This release supports the full range of VPI values: 0 to 255. However, if you configure VP tunnels with traffic shaping, you can use only 32 VPIs out of that range. If you have not yet assigned any VPIs, all values from 0 to 255 are available. Once you start assigning VPIs, however, the assigned VPIs limit the VPIs that remain. (You assign VPIs using the atm pvp or atm pvc command.)

After a particular VPI value is assigned to a shaped VP tunnel, every 32nd VPI value above and below the first one is eliminated—that is, the original value modulo 32. For example, if you assign VPI 94 to a shaped VP tunnel, the following VPI values become unavailable for any purpose: 30, 62, 126, 158, 190, and 222.

To avoid problems, choose a block of 32 consecutive VPI values (for example, 0 to 31 or 101 to 132). The software rejects invalid VPI values.

Installing Multiple Cisco 6160 Chassis in an Equipment Rack

You can install multiple Cisco 6160 chassis in a telco equipment rack. A standard 7-foot equipment rack can house four Cisco 6160 chassis, stacked one on top of another. This configuration maximizes the DSL density within a 7-foot rack. However, if space is available or if you are interested in using multiservice capabilities that the chassis will support in the future, we recommend that you install no more than three Cisco 6160 chassis within a 7-foot rack. Leave a space of at least 2.5 rack units (4.375 inches, or 11.1 cm) beneath each chassis for future cable management use.

Console Logging

Turn console logging off if you plan to reboot the DSLAM. Turn console logging back on after the system comes up. (Console logging is turned on by default.) Use the global configuration commands no logging console (to turn the feature off) and logging console (to turn it on).

If console logging is on when the system reboots, the large volume of console messages consumes CPU time. As a result, the system comes back up more slowly and line cards might reload repeatedly, causing further delays.

Caveats

Caveats describe unexpected behavior in Cisco IOS software releases. Severity 1 caveats are the most serious caveats; severity 2 caveats are less serious. Severity 3 caveats are moderate caveats, and only select severity 3 caveats are included here.

This section contains only open, closed, and resolved caveats for the current Cisco IOS release.

Caveat numbers and brief descriptions are listed in Table 4, Table 5, Table 6, Table 7, Table 8, Table 9, Table 10, and Table 11. For details about a particular caveat and for information on caveats in previous Cisco IOS releases that also apply to this release, go to Bug Toolkit at:

http://www.cisco.com/cgi-bin/Support/Bugtool/launch_bugtool.pl

To access this location, you must have an account on Cisco.com. If you have forgotten or lost your account information, e-mail the Contact Database Administration group at cdbadmin@cisco.com. If you do not have an account on Cisco.com, go to http://www.cisco.com/register and follow the directions to set up an account.


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, go to Cisco.com and click Login. Then go to Software Center > Cisco IOS Software > Cisco Bugtool Navigator II. Alternatively, you can go to

http://www.cisco.com/cgi-bin/Support/Bugtool/launch_bugtool.pl


This software release is based on Cisco IOS Release 12.2. For information on caveats in Cisco IOS Release 12.2, see Caveats for Cisco IOS Release 12.2, which lists severity 1 and 2 caveats and select severity 3 caveats for Cisco IOS Release 12.2. It is located on Cisco.com and the Documentation CD-ROM.

Resolved Caveats—Release 12.2(10)DA1

Table 3 lists the caveats that have been resolved in Cisco IOS Release 12.2(12)DA1.

Table 3 Resolved Caveats in Cisco IOS Release 12.2(10)DA1 

Caveat Number
Description

CSCea38684

FTP fails with the traceback: SYS-2-LINEPROCDEAD: Killing process

CSCea50123

Ftp sessions on NI2 will abort the file transfers occasionally without any error messages or notifications to the user.


Open Caveats—Release 12.2(10)DA

All the caveats listed in Table 4 are open in Cisco IOS Release 12.2(10)DA. This table lists only severity 1 and 2 caveats and select severity 3 caveats.

Table 4 Open Caveats for Cisco IOS Release 12.2(10)DA

Caveat Number
Description

CSCdx53819

8xDMT cards with interleaving delay configurations of 2000us and below have problems holding train and/or having less than expected upstream train rates.

Workaround: Avoid interleaving delay values of 2000us and below with 8xDMT cards. Interleaving mode configurations should use 4000us delay or above. If lower delays are required, Fastpath mode can be used if supported by CPE being used.

CSCdx57259

The connection between the modem on a 4xDMT line card and the CPE is lost when an NI-2 redundancy switchover occurs.

Workaround: None.

CSCdx67720

When you copy a configuration file from a tftp server to the startup_config through snmp, ccCopyState (CISCO-CONFIG-COPY-MIB) will be in "running" state ever after. It will not change to "Failed" state.

The show startup command displays the following output:

%% Non-volatile configuration memory is being accessed, Try again

Workaround: Make sure that there is enough space available in the nvram before copying, using snmp or use cli.

CSCdx84898

Upgrades from Cisco IOS 12.1(7) DA to newer IOS images cause G.SHDSL ports to occasionally drop and retrain. The error is listed as LOSQ (Loss of Signal Quality) due to CRC errors detected or LOS when Loss of Frame Sync. is detected.

Workaround: Newer versions of G.SHDSL firmware have been adjusted to meet the ratified standards. This may require some fixed-rate loops to not hold train at the current configured rate used with Cisco IOS 12.1.(7)DA. Reducing the configured rate in some cases will resolve the issue. Random drops may still occur on some ports.

CSCea56851

3db downstream margin configured ports on 8xDMT do not achieve max configured downstream rate on loops that should achieve max configured downstream rate.

Workaround: Use of DSL's recommended 6db downstream margin will achieve max configured rate on loops expected to achieve max rate.


Open Caveats—Release 12.2(7)DA

All open caveats in Cisco IOS Release 12.2(7)DA have been resolved.

Open Caveats—Release 12.2(5)DA

All the caveats listed in Table 5 are open in Cisco IOS Release 12.2(5)DA. This table lists only severity 1 and 2 caveats and select severity 3 caveats.

Table 5 Open Caveats for Cisco IOS Release 12.2(5)DA 

Caveat Number
Description

CSCdv32720

The 8xDMT over ISDN line card does not recognize the dying gasp messages from any CPE. The Far End LPR Events counter in the show dsl interface atm x/y command does not increment when dying gasp messages are sent from a CPE.

Workaround: None


Closed Caveats—Release 12.2(5)DA

All the caveats listed in Table 6 are closed without resolution in Cisco IOS Release 12.2(5)DA. This table lists only severity 1 and 2 caveats and select severity 3 caveats.

Table 6 Closed Caveats for Cisco IOS Release 12.2(5)DA

Caveat Number
Description

CSCdt27044

Filesys space error is displayed when you perform the first write mem command following a reload.

CSCdt27246

CIB Save FAILED message is displayed during NI-2 boot.


Open Caveats—Release 12.2(1b)DA

All the caveats listed in Table 7 are open in Cisco IOS Release 12.2(1b)DA. This table lists only severity 1 and 2 caveats and select severity 3 caveats.

Table 7 Open Caveats for Cisco IOS Release 12.2(1b)DA 

Caveat Number
Description

CSCdt81452

PPP negotiation does not occur if the ppp encapsulation command references a nonexistent virtual template.

Workaround: Configure a complete virtual-template interface first, and then configure the PPP PVC.

CSCdu10692

If you configure no ip cef and ip cef in very quick succession, MPLS ceases operating and the show mpls forwarding command reports that tag switching is not operational. CEF or tag switching has not been enabled.

Workaround: Configure no ip cef, wait 2 seconds, and then configure ip cef.

CSCdu39970

A per-user route from a previous IPCP subnet negotiation might appear in the routing table after the PPP circuit has been added again with a no pvc X/Y command and then followed by the pvc X/Y command.

Workaround: Use the no ip route command to remove the stale per-user route.

CSCdu46804

IP address negotiation via IPCP to an external DHCP server across an ATM link fails.

Workaround: Use a local DHCP server connected on the Ethernet segment.

CSCdu74113

If you use NAS-PORT format D, the underscore delimiter is missing in the Acct-Session-Id attribute.

Workaround: None.

CSCdu78386

The static VRF route applied on the PE does not take effect. There is no connectivity if you use static routing over MPLS/VPN.

Workaround: Redistribute static or RIP route into BGP from the egress PE; the ingress PE will learn the egress PE VPN routes.

CSCdv05322

Attainable bit rate is conservative for 4xFLEXI-DMT.

Workaround: None. The aggregate bit rate calculation is an estimate, which does not accurately model all of the line conditions that affect the true attainable bit rate for a given profile.


Resolved Caveats—Release 12.2(10)DA

The problems listed in Table 8 are fixed in Cisco IOS Release 12.2(10)DA.

Table 8 Caveats Resolved in Cisco IOS Release 12.2(10)DA 

Caveat Number
Description

CSCdp00996

Periodically, the system generates a serial management bus cyclic redundancy check (SMBCRC) error message such as this:

%NI2-5-LC_NOTICE:Slot[15] SMBCRC (1 days, 3 hours, 37 minutes, 6 seconds)

These messages are informational only and do not affect performance.

CSCdu04045

The entry for the atmSoftPVccRetryThreshold feature has an incorrect default value of 0, rather than the default value of 1 that is shown in the ATM Soft PVC Management Information Base (MIB). A value of zero indicates that an infinite number of call attempts are required to increment the atmSoftPvcCallFailures object and thus disables alarms for the Soft PVCC.

CSCdu40049

Adding and deleting a profile from different sessions (for example, in two telnet sessions, one user is adding while at the same time another is deleting the same profile) has the potential of causing an unexpected system reload.

CSCdu42394

The ceAssetTag cannot be set for 8xDMT and SHDSL line cards.

CSCdv56813

Following a redundancy switchover, the standby card may reload twice before reaching the STANDBY-READY state. Once the standby is in the STANDBY-READY state it will not continue to reload.

CSCdv73591

Some VCs (PVCs/PVPs/Soft PVCs/Soft PVPs) are missing on reload even when they are stored in the startup configuration. This problem occurs if you create VC's by using internal CTT rows that do not appear in the show running-config command but do appear in the show atm connection-traffic-table command.

CSCdw53009

When you configure the ATUC-1-4DMT line card for loopback diagnostic, cells are dropped by the interface.

CSCdw67176

The commands no tag-switching ip and tag-switching ip from the global configuration mode remove the tag-switching atm vp-tunnel 13 vci-range 33-65535 line on the sub interfaces.

CSCdw73531

Not all IMA group/link alarms are shown in the event browser.

CSCdw87272

If you try to enable tag-switching ip, the following message is returned: %VP-tunnel vpi is not free for Tag-switching.

CSCdw91698

The NI-2 does not support OAM F5 seg-loopback cells, in the fast path.

CSCdx16449

PNNI fails to establish a connection. The show atm controller atm 0/0 command displays a status of C.

CSCdx19656

Unable to train with 3Com OCR-810. With the 4xDMT line card, the CPE had a number of line errors or fails to train with 12.2(7)DA. Trellis coding is enabled in the DSL profile.

CSCdx34262

When you change the operation of the linecard from ATUC-1-DMT8 to STUC-8-TCPAM, the indexes appear in the incorrect order.

CSCdx43027

System hangs indefinitely after provisioning/unprovisioning slots.

CSCdx64312

In Cisco IOS images 12.2(7)DA, the value of the "Microseconds handling network interrupts" is not saved correctly to the NVRAM when configured via the scheduler allocate exec command.

CSCdx65171

The NI-2 unexpectedly reloads when you try to clear a card mismatch from CLI using the command no slot x, where x is the slot number.

CSCdy02467

Adtran CPE do not train with the Cisco 6260 running Cisco IOS 12.2(7)DA.


Resolved Caveats—Release 12.2(7)DA

The problems listed in Table 9 are fixed in Cisco IOS Release 12.2(7)DA.

Table 9 Caveats Resolved in Cisco IOS Release 12.2(7)DA 

Caveat Number
Description

CSCdp68075

The input queue field in the output of the show interface atm slot/port occasionally shows a negative number.

CSCds48063

The cAdslAtuc/AturCapCurrRxGain in the CISCO-ADSL-CAP-LINE-MIB returns an incorrect value for short loops ( less than 2000 feet).

CSCds51529

For the STUC G.SHDSL line card, all far end (STUR) statistics that display through the CLI or SNMP are reported as zero.

CSCdt87954

The G.SHDSL line card does not support rate adaption.

CSCdu00802

The ifSpeed object from the ifTable returns an incorrect speed at the ATM layer for a 4xFlexi DMT line card.

CSCdu35160

Packet loss occurs when you police with abr for MCR values greater than 18.

CSCdu48003

The Init event counter toggles between 0 and 4294967295 several times in a minute for a 4xFlexi DMT line card.

CSCdu81936

An ARP packet received by the router that has the router's own interface address but with a different MAC address can overwrite the router's own MAC address in the ARP table, causing that interface to stop sending and receiving traffic. This attack is successful only against interfaces on the Ethernet segment that is local to the attacking host.

CSCdv12425

The error message ERROR: Irrecoverable IDT 252 RCQ last Cell problem detected! appears and is repeated several times. ATM oam cells are not handled correctly and these error messages finally lead to system reload.

CSCdv30504

Far End LPR Events are not incrementing on the ATUC-4FLEXI-DMT line card when the power is removed from a CPE that supports the dying gasp feature of the DMT standard.

CSCdv38294

VPI/VCI values for provisioned PVC do not match the provisioned values when you select a VCI value of 0 for any non-terminating PVC (that is, a PVC not terminating at atm0/0).

CSCdv80202

The shdsl profile has a different format between Cisco IOS Release 12.1(7)DA and Cisco IOS Release 12.2(5).

CSCdv86663

When you configure an interface bandwidth statement on a Cisco 6260 ATM interface, the default bandwidth value for the interface as seen in the show interface atm command may appear in the show running-config output.

CSCdw03128

Cisco 6260 SNMP agent returns wrong ifType for SHDSL interfaces.

CSCdw25440

Using the command show atm vc interface atm slot/port vpi vci where vpi and vci are the vpi and vci numbers in a SVC configuration can cause the DSLAM to reload. This usually happens when the CPE is connected but the SVC is not yet established.

CSCdw34798

Invalid cells are passed to network port on a valid VC. The 4xDMT line card does not discard cells with HEC errors and stamps each cell going to the DSLAM with a valid HEC. The switch can then pass these corrupt cells out the WAN interface if they appear to have a valid and provisioned VPI and VCI.

CSCdw41743

After 54 days of uptime, the system experienced an unexpected reload immediately preceded by the messages: System reloads with message SYS-2-WATCHDOG process=IMA CORE.

CSCdw47576

An NI-2 DSLAM reloads after a few ALIGN-1-FATAL error messages.

CSCdw65903

An error can occur with management protocol processing. Please use the following URL for further information:

http://www.cisco.com/cgi-bin/bugtool/onebug.pl?bugid=CSCdw65903


Resolved Caveats—Release 12.2(5)DA

The problems listed in Table 10 are fixed in Cisco IOS Release 12.2(5)DA.

Table 10 Caveats Resolved in Cisco IOS Release 12.2(5)DA 

Caveat Number
Description

CSCdt89256

Cisco 6160 DSLAM does not recognize the debug atm oam command.

CSCdt91908

When an IMA group and some of the links in the group are administratively shutdown, the IMA group cannot recover.

CSCdu06659

GETNEXT fails for all entries in cAdslAtucDmtChanTable.

CSCdu06678

GETNEXT fails for all entries in cAdslAturDmtChanTable.

CSCdu15630

Auto-sync of startup-config does not always work.

CSCdu17222

The port state that the show aps command displays for the subtend port on the standby card is not valid until the peer state indicated by the command show redundancy states is "STANDBY READY".

CSCdu18944

When both NI-2s in a redundant configuration reboot simultaneously, the standby card may reboot more than once if the configuration file is very large.

CSCdu24772

System shows secondary running config failed during RF progression.

CSCdu35414

Auto-sync of running config can cause write command to fail.

CSCdu44723

The show facility-alarm status command displays incorrect message.

CSCdu75769

When you issue an atm oam intercept end-to-end command, an error message appears.

CSCdu76334

SNMP query for the MIB objects adsl[Atuc/Atur]ChanCurrTxRate (ADSL-LINE-MIB) returned swapped values for CAP line card.

CSCdu80361

Failed to set overhead framing structure to structure0 in DMT.

CSCdu83833

CLI command snmp get/set is seen via CLI help.

CSCdv15430

Stur objects are not supported on SHDSL.

CSCdv23151

A DMT interface configured to use fast channel returns values on this interface's adslAtucChanIntervalTable and adslAturChanIntervalTable.

CSCdv32861

The mib object atmInterfaceMyNeighborIpAddress in the ATM mib can contain incorrect address.

CSCdv38540

Ping not responding but Telnet works.

CSCdv39307

Some ports of flexiCAP lock up as trained even when CPE is untrained.

CSCdv52839

When more than 150 PVPs are configured, the Cisco 6260 DSLAM cannot be booted after a power cycle or a reload.

Workaround: Power-off the DSLAM, "break" into rommon, boot the DSLAM without parsing the configuration, and copy the startup to running-config.

CSCdv62132

Cisco 677 retrains on Cisco 6260 DSLAM with 8xDMT line cards.

CSCdv61164

cAdslAtucCapCurrRxSnr is reporting in dB, where as the MIB definition states that it should be reported in 1/10th dB.


Resolved Caveats—Release 12.2(1b)DA

The problems listed in Table 11 are fixed in Cisco IOS Release 12.2(1b)DA.

Table 11 Caveats Resolved in Cisco IOS Release 12.2(1b)DA 

Caveat Number
Description

CSCdr38060

Add attainable bit rate on 4xflexi DMT.

CSCdr96185

When you are executing a show version command, SHDSL ports are shown as SDSL ports.

CSCds14884

No log event link-status command has no effect.

CSCds15469

IP MTU or Physical MTU setting has no effect on fragmentation.

CSCds80863

MIB adslAtucCurrStatus returns incorrect value for CAP and DMT.

CSCds81122

MIB adslAturCurrStatus returns incorrect value for DMT.

CSCdt11375

Performance interval counters are not correct for G.SHDSL.

CSCdt34090

Profile created from altered default has different parameters.

CSCdt71353

Minimum DMT bitrate setting is lost after upgrade.

CSCdt73955

The delay does not change when oamLoopbackPingDelay is changed.

CSCdt75675

Link down traps are not reliably sent for IDSL.

CSCdt76848

SDSL profile lists rates of 1552, 2064, and 2320 and allows their use.

CSCdt79352

MIB adslAturChanTransmittedBlks has a MIB value of 0 but CLI has non-0.

CSCdt79387

adslAturVendorID will return 0 from MIB, CLI has 57 (Globespan).

CSCdt79394

MIB adslAtucChanCrcBlockLength always has a value of 0.

CSCdt79405

MIB adslAturChanCrcBlockLength always has a value of 0.

CSCdt79412

MIB cIdslItucInvSerialNumber returns garbage instead of empty string.

CSCdt81887

IMA group collapses when differential delay changed on one line.

CSCdt88209

Some DSL statistics missing in Cisco IOS 12.1(5)DA for DMT cards.

CSCdt94063

OAM ping of IMA group depends on state of CPE connection.

CSCdu05779

MIB imaGroupLeastDelayLink is not supported in MIB.

CSCdu06348

SDSL attempts to report LOS events instead of LOSQ in the show dsl interface display.

CSCdu07798

PEM alarm does not clear after hot swap replacement.

CSCdu11030

MIB imaGroupTestProStatus does not match CLI.

CSCdu11335

MIB: All Prev1Day performance counters are always zero.

CSCdu11634

Line ports reset when CPU usage is high.

CSCdu12291

Issuing show run on the NI-2 results in SNMP query timeout.

CSCdu17619

Attainable aggregate bitrates do not apply to 8xDMT.

CSCdu20810

CPU utilization is degrading.

CSCdu26649

MIB SONET physical layer does not match logical layer.

CSCdu35353

Limitation to 32 VPI values even if the VP tunnels are not shaped.

CSCdu44511

8xDMT is unable to train at 1024 kbps upstream with Cisco 678.

CSCdu45628

IOS reloads with update_the_1day_counts on top of stack.

CSCdu47978

Init Event counters toggle between 0 and max int in 8xDMT cards.

CSCdu48059

Inconsistent counter operations exist for Atuc/Atur IntervalEntry fields.

CSCdu57284

ItucIntervalNumber is more than 96 while querying ItucIntervalTable.

CSCdu64006

Soft PVC address on the Cisco 6260 DSLAM is changed after upgrade.

CSCdu71803

When an F4 OAM atm seg cell, with a PT field set for end-to-end type, is received on nonprovisioned VP, the system reloads.


Related Documentation

The software described in these release notes runs on several Cisco NI-2 DSLAM platforms, including the Cisco 6015 DSLAM, Cisco 6160 DSLAM, and Cisco 6260 DSLAM. The sections below list related documentation.

Hardware Documentation

A complete list of all DSL hardware product related documentation is available on the World Wide Web at

http://www.cisco.com/univercd/cc/td/doc/product/dsl_prod/index.htm.

Software Documentation

A complete list of all DSL Cisco IOS product related documentation is available on the World Wide Web at

http://www.cisco.com/univercd/cc/td/doc/product/dsl_prod/ios_dsl/index.htm.

In the Cisco ATM software manuals, look for information pertaining to the LightStream 1010, which uses the same software base as the NI-2 DSLAMs. ATM manuals are on the World Wide Web at

http://www.cisco.com/univercd/cc/td/doc/product/atm/index.htm.

Obtaining Documentation

The following sections provide sources for obtaining documentation from Cisco Systems.

World Wide Web

You can access the most current Cisco documentation on the World Wide Web at the following sites:

http://www.cisco.com

http://www-china.cisco.com

http://www-europe.cisco.com

Documentation CD-ROM

Cisco documentation and additional literature are available in a CD-ROM package that ships with your product. The Documentation CD-ROM is updated monthly and is available as a single unit or through an annual subscription.

Registered Cisco.com users can order the Documentation CD-ROM through the online Subscription Store:

http://www.cisco.com/go/subscription

Nonregistered Cisco.com users can order the Documentation CD-ROM through a local account representative by calling Cisco corporate headquarters (California, USA) at 408 526-7208 or, in North America, by calling 800 553-NETS(6387).

For assistance with ordering, contact your distributor or see the Cisco Technical Assistance Center website at:

http://www.cisco.com/tac

Documentation Feedback

If you are a registered Cisco.com user, you can submit technical comments electronically.

To report problems, click Feedback in the toolbar at the top of any document web page and select Report a Problem. Under Problem Type, select CD/Online Documentation. After you complete the form, click Submit to send it to Cisco.

You can also e-mail your comments to bug-doc@cisco.com.

To send your opinion of the DSL documentation, go to the following URL:

http://www.cisco.com/univercd/cc/td/doc/product/dsl_prod/

and click here at the top of the page in the sentence "Is this Cisco documentation helpful? Click here to give us your feedback." This produces a Documentation Survey that you can complete and send to Cisco electronically.

To submit your comments by mail, write to the following address:

Cisco Systems
Attn: Document Resource Connection
170 West Tasman Drive
San Jose, CA 95134-9883

We appreciate your comments.

Obtaining Technical Assistance

Cisco provides Cisco.com as a starting point for all technical assistance. Customers and partners can obtain documentation, troubleshooting tips, and sample configurations from online tools. For Cisco.com registered users, additional troubleshooting tools are available from the TAC website.

Cisco.com

Cisco.com is the foundation of a suite of interactive, networked services that provides immediate, open access to Cisco information and resources at anytime, from anywhere in the world. This highly integrated Internet application is a powerful, easy-to-use tool for doing business with Cisco.

Cisco.com provides a broad range of features and services to help customers and partners streamline business processes and improve productivity. Through Cisco.com, you can find information about Cisco and our networking solutions, services, and programs. In addition, you can resolve technical issues with online technical support, download and test software packages, and order Cisco learning materials and merchandise. Valuable online skill assessment, training, and certification programs are also available.

Customers and partners can self-register on Cisco.com to obtain additional personalized information and services. Registered users can order products, check on the status of an order, access technical support, and view benefits specific to their relationships with Cisco.

To access Cisco.com, go to the following website:

http://www.cisco.com

Technical Assistance Center

The Cisco TAC website is available to all customers who need technical assistance with a Cisco product or technology that is under warranty or covered by a maintenance contract.

Contacting TAC by Using the Cisco TAC Website

If you have a priority level 3 (P3) or priority level 4 (P4) problem, contact TAC by going to the TAC website:

http://www.cisco.com/tac

P3 and P4 level problems are defined as follows:

P3—Your network performance is degraded. Network functionality is noticeably impaired, but most business operations continue.

P4—You need information or assistance on Cisco product capabilities, product installation, or basic product configuration.

In each of the above cases, use the Cisco TAC website to quickly find answers to your questions.

To register for Cisco.com, go to the following website:

http://www.cisco.com/register/

If you cannot resolve your technical issue by using the TAC online resources, Cisco.com registered users can open a case online by using the TAC Case Open tool at the following website:

http://www.cisco.com/tac/caseopen

Contacting TAC by Telephone

If you have a priority level 1(P1) or priority level 2 (P2) problem, contact TAC by telephone and immediately open a case. To obtain a directory of toll-free numbers for your country, go to the following website:

http://www.cisco.com/warp/public/687/Directory/DirTAC.shtml

P1 and P2 level problems are defined as follows:

P1—Your production network is down, causing a critical impact to business operations if service is not restored quickly. No workaround is available.

P2—Your production network is severely degraded, affecting significant aspects of your business operations. No workaround is available.


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Posted: Fri Nov 3 16:58:12 PST 2006
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