my company Cisco IP Phones from time to time switch their state to registering to return after some minutes to full functionality.
As I've to investigate the matter, I'd like to know for sure what this state mean.
Is this a message generated ,as I guess, by the unavailability of the call manager? If so I could exclude problem in external (provider's) lines and concentrate on the LAN side.
Registering means that phone has unregistered and is re-registering. Unfortunately the new phones/callmanager versions, do not show exactly at what stage the phone is at during the registering phase. Old phones/callmanagers would show dhcp/tftp/updating firmware...., so there was more info on the phone display to assist in troubleshooting.
Do a show interface gx/x and verify there are not any errors/speed duplex mismatch.
I would also browse to the phone's ip address and click on consle logs. The log may provide some information to the reason for unregistering.
There are some bugs out there concerning intermittently unregistering and re-registering.
