[c-nsp] Same MAC on different VLAN

[Dale Shaw]

Hi Leslie,

On Sat, Mar 5, 2011 at 10:15 AM, Keegan Holley
<keegan.holley at sungard.com> wrote:
> Your phone is trunking and it is in both vlans at the same time.  Any device capable of dot1q tagging packets can appear in multiple vlans.  When that happens it doesn't change it's mac and this is the result.

I agree with Keegan.

If the MAC entry in the native VLAN (VLAN 26) stays there (doesn't age
out), it's probably because the phone is sending untagged CDP frames.
The switch must be receiving some untagged frames from the phone's
MAC, anyway.

Of course, the tagged voice (signalling and media) frames received
ensures the MAC entry in VLAN 172 stays put.

Cheers,
Dale