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CDP Issue - phone being assigned to wrong vlan

on a 6500 with Polycom stations connected to a PoE switch module:

The polycom ip 430 phones support CDP and the switch is normally able to assign them to the voice vlan without any problems. however, we just encountered an issue today where the phone is not being placed into the voice vlan - instead it is being placed into the access vlan. this is happening on 2 of my 3 switch modules.

however, if I move the phone to a port on the 3rd switch module, cdp is recognized just fine and the phone is placed into the correct voice vlan.

I have enabled 'debug cdp packets' but nothing special in the output when i remove/reconnect the phone to the ports..

Update: The affected ports seem to be within the first 8 of each of the two switch modules. f1/2, 1/4, 2/7, 2/3, etc. If I move the phone to a port somewhere down the card, it works properly. Could it be that the asic assigned to those first set of 8 ports is having a problem? FYI: the switch modules are WS-X6148A-45AF (48 port 10/100, PoE)

Another update: It seems that all ports on switch ports 1/1 - 1/8 and 2/1 - 2/8 are affected.. and it's more than just phones... all traffic is broken. This is really looking like an asic problem, however, it's hard to believe that 2 asics on 2 different switch modules could go bad at the same time.



Re: CDP Issue - phone being assigned to wrong vlan

have you tried reseating the modules? powering them down then up again?

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