Alcatel Carrier Internetworking Solutions 8800 User Manual

Writing a PR for Spanning Tree

Troubleshooting Spanning Tree

page 4-26

OmniSwitch Troubleshooting Guide

The following subsections describe some guidelines to follow when writing a PR that addresses Spanning 
Tree. Please note that the following subsections use Dshell commands, not CLI commands.

Note. Dshell commands should only be used by Alcatel personnel or under the direction of Alcatel. 
Misuse or failure to follow procedures that use Dshell commands in this guide correctly can cause lengthy 
network down time and/or permanent damage to hardware.

When there is an exception in a task, the task is suspended by the Operating system. This could happen 
when the application tries to access to an un-aligned memory area, release of buffer that is already release, 
etc. If the Spanning Tree does not respond, ask for the task information (i Dshell command). If the task is 
suspended do the following:

1 Get the task registers with the ti task_id command.

2 Get the task stack with the tt task_id command.

3 Disassemble the code around the faulty PC (exception program counter).

Note. Perform the step above between address - 0x20 and address+0x100.

If the show spanning tree command indicates that the port is forwarding, but no traffic is seen through that 
port do the following:

1 Perform the following steps on the NI:

a  Select the suspected NI (changeSlot).

b Dump the event trace (stpni_traceprint).

c Dump the port trace (stpni_debugport).

2 Perform the following steps on the CMM.

a  Dump the event trace.

b Dump the Spanning Tree memory for the VLAN (0x6608000+(vlan_id*4))