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New Member

Debug question

We're having problems with our new 2960G stack with port flapping.  I'm sure, at this point, the problem is cabling ( its old cat5 ), but I'd like to run some debugging on this stack for a little while to see what the switch has to say.

What debug command can I use to watch a port and see what messages it is generating while it is flapping?

I have looked though the extensive list of debug items, but am unsure which to use.  I've also got 600 things that need doing and don't have the time to properly research this.

Thank you in advance for any advice ; )

  • LAN Switching and Routing
Cisco Employee

Re: Debug question

You may try these debugs, however output might not be user friendly, as it's platform specific:

debug interface
debug condition interface
debug platform phy link-status

Do ensure, to disable/tweak console and monitor logging, so it does not kill the CPU.

- logging console 6

- logging monitor 6


- no logging console

- no logging monitor

Buffer logging might be increased, and enabled for debugging (which is by default)

- logging buffer 7

- logging buffer 56000





Re: Debug question

Also note that debug logs will only appear where you configure debugging severity (which is 7). If you want to see the debugs on a telnet/ssh session, enable monitor logging 7 and don't forget to issue the 'terminal monitor' (term mon) command to see the debug messages.

New Member

Re: Debug question

Thank you for the pointers here folks, I appreciate your time.

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