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PCM cannot discover edge swich links


PCM cannot discover edge swich links

I am having a problem at one site I am monitoring, PCM2.1 will map out all the switches in all of my sites except one. At this site, I have a 4000m as the core and 4 stacks of 2524's PCM will map out the core switch and correctly put in the commander 2524 for the stacks, but even though I have all the child swiches in the stacks configured with IP's it will not map them. I even tried breaking the stack on one area, and just using the stacking modules as uplinks. Still unable to discover the link to the rest of the switches.
Any ideas???
Matt Hobbs
Honored Contributor

Re: PCM cannot discover edge swich links

Hi Rob,

I have a theory, I don't know how accurate it is though..

With the latest F.05.xx firmware on the 2500 it introduced limited LLDP support and removed CDP.

What I'm guessing is happening is the 4000M is still happily sending it's CDP packets which the first 2500 in the stack is accepting.

The 2500's themselves though are only sending LLDP packets, they do not read them. This is why the other 2500's are not showing up in the topology map.

To confirm this theory, you could roll back to a pre F.05.50 version and see if that helps.


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