Cisco – Spanning-Tree debug logs C7600

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I am trying to debug STP on a C7613 but I have logging issues.
IOS version 15.2(4)S2
The Route Switch Processor is RSP720-3CXL-GE

I'm running every debug commands for Spanning-Tree but nothing gets shown either on the console or in the logs.

Here are my debug commands : 

debug spanning-tree events
debug spanning-tree bpdu receive

I know that RSTP is running on my switch, as well as my ports are receiving BPDUs all the time. I should see traffic with this debug.

Here is the logging config : 

logging buffered 10000000000
logging monitor debugging
logging alarm informational
logging trap debugging
logging facility local2
logging host 10.162.33.69
logging console

Why is it that I cannot see anything in the logs from this debug ?
Also, I tried with a CDP debug and all the debug logs were seen in the logs buffer. This seems like a STP issue.

Thanks for the help

Best Answer

The RSP720 in the router has two processing engines. The route processor (RP) and the switch processor (SP).

When you log-in to the console/telnet/ssh on a 7600 that's running IOS on both the RP and the SP (Native mode), you log-in to the RP by default. The spanning-tree function is however performed by the SP.

After logging into the box try:

term mon
remote command switch debug spanning-tree bpdu receive

You should see some output. The debug must also be turned off using the remote command switch command.

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