8941 phones not registering

[richb1971]

We have 8941 SCCP phones that do not re-register if a PC/Laptop is connected to phone and we shut/no shut the Cisco switchport. The phone loses its default gateway and cant register.

Weird. Any one seen before?

Rich

[Manish Gogna]

Hi Rich,

Is the 'Auto Port negotiation" setting enabled on the phone on cucm admin page. If yes, try disabling it and check if the issue still persists.

HTH

Manish

[richb1971]

Hi Manish,

Already disabled :(

The phone re-registers if I clear DHCP binding! Far from ideal. Whats preventing it from re-registering?

Rich

[richb1971]

Bug!

Symptom:
From the phone go to Settings > Administrator Settings > Reset Settings > Network Settings > RESET > then the phone will release its IP Address, perform a DHCP Discover > receive and Offer > then do a DHCP Request > for which it receives a DHCP Ack but does not take the IP, it will just stay unregistered and trying to get an IP.

8945 dhcp renewal stalls due to buffer size limitation - CSCuh56919