Re: Strange CDP Observation

Yes you have a loop somewhere in your L2 network that you need to trace down. I have seen this before and it turned out to be a hub stuck somewhere in the middle of a loop.

Switch1--hub--Switch1
------Original Message------
From: Felix Nkansah
Sender: nobody_at_groupstudy.com
To: cisco-nsp_at_puck.nether.net
To: CCIE Groupstudy
ReplyTo: Felix Nkansah
Subject: Strange CDP Observation
Sent: Nov 28, 2009 5:42 PM

Hi Team,

One of my field engineers at a remote site has reported a problem to me, one
which I find rather strange but yet to confirm for myself.

A Catalyst 2960 switch at the remote site is linked to a switch at a Central
site via radio (bridged).

However, besides the fact that connectivity tests between the two sites are
failing, his observation is that when he issues the "SHOW CDP NEI" command
on the remote C2960 switch, he sees the switch itself appearing as its
neighbor rather than the other switch at the central location which is
typically the output he expected.

I have personally never seen a Cisco device showing itself as it's own
neighbor in a 'show cdp neighbor' output.

What do you know to be the cause of this problem?

Thanks.

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Received on Sat Nov 28 2009 - 23:37:48 ART