Unexpected Voice VLAN Traffic

Unanswered Question
Apr 30th, 2009

I'm seeing some traffic from the voice VLAN when sniffing on one of my servers. Mostly broadcast, but occasionally unicast traffic between the CMs and some phones.

When I remove the "switchport voice vlan" command from the interface which is connected to the server the traffic goes away. The traffic is untagged and there isn't a phone between the server and the switch.

This is really unexpected since I didn't think the switch would send traffic from the voice VLAN only if it detected a phone via CDP and if it did send traffic I would expect it to be tagged traffic.

Any ideas on why I am seeing this traffic?

Thanks for any help,


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Dennis Mink Fri, 05/01/2009 - 04:33


since you are sniffing, what type of trafic is it? what TCP or UDP ports is it trying to connect to?


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