I had an issue with 6921 phones not staying in the correct VLAN.
Here's the sample config:
interface f0/1
switch access vlan 50
sw voice vlan 900
sw mode access
The configuration initially worked. I was resetting and rebooting the phones and switches several times. Then 80% of my phones would not re-register after a reset. It seems that the phones were getting an IP address in the access VLAN range. The only workaround was to remove the switch access vlan 50 configuration and let the phone register. After that the access VLAN 50 configuration was added, and the phones have always booted in the voice VLAN.
Has anybody else experience this issue? Has it been resolved?
