Cisco WAN Switching Modules

August 24, 1999

Products Affected

Problem Description

Automatic Protection Switching (APS) fails to operate properly resulting in trunk or port outages.

Problem Symptoms

The main symptom that the user will observe is the BXM card with the lower hardware will show "Mismatch" and the dspcd slot_number screen will show that APS(1+1) is not supported.

Background

APS is used to provide additional redundancy robustness over the legacy Y-redundancy capability. This feature allows either front card to operate with either backcard in the APS pair. Both 1:1 and 1+1 redundancy modes are supported.

In order to support the APS feature, a new, two-slot "mini-backplane" was implented that draws power from the BXM card. The new hardware requires a higher output power on the BXM. The higher power supplies were implemented in BXM hardware revision E for the BXM-622 cards and BXM hardware revision C for the remaining BXM models.

This hardware dependency does not exist with Enhanced BXM cards.

Workaround/Solution

Workaround: Use Y-redunancy instead of APS.

Solution: RMA BXM cards. The BXM hardware revisions that support APS are as follows:

• Rev E BPX-BXM-622-2

• Rev E BPX-BXM-622

• Rev C BPX-BXM-155-8

• Rev C BPX-BXM-155-4

• Rev C BPX-BXM-T3-12

• Rev C BPX-BXM-T3-8

• Rev C BPX-BXM-E3-12

• Rev C BPX-BXM-E3-8

Hardware revisions later than the above revisions also support APS. It is important to note that the hardware revisions that support APS have been in production since December 1997.

RCN

How To Identify Hardware Levels

Use the dspcd slot_number command.

BPX1           TN    StrataCom       BPX 8600  9.1.1X    Aug. 5 1999  11:48 PST
                                   
Detailed Card Display for BXM-155 in slot 10
Status:          Active
Revision:        CDA    <-- Middle letter is the hardware revision.
Serial Number:   770061
Fab Number:      28-2158-02
Queue Size:      228300
Support:   FST, 8 Pts,OC3,VcShpng
Chnls:16320,PG[1]:7048,PG[2]:7048
PG[1]:1,2,3,4,
PG[2]:5,6,7,8,
Backcard Installed
Type:          LM-BXM
Revision:      P05
Serial Number: 474877
Supports: 8 Pts, OC3, SMF Md

Last Command: dspcd 10
                                   
Next Command:

For More Information

If you require further assistance, or if you have any further questions regarding this field notice, please contact the Cisco Systems Technical Assistance Center (TAC) by one of the following methods:

• Open a service request on Cisco.com
• By email
• By telephone

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