Help!!!! Service Critical/CM List error

[Planetmaker]

We have one site that has a its own device pool locations etc - 65% of the phones are (all of a sudden) not registrering. They seem stuck on "Configuring CM lIst"
Can some one explain why this may be?
I have deleted one that is n't working add manully added it again but still no joy I have even deleted its ip address but doesn't seem to want to pick up a new one.
Seems strage that some are ok others not and its not a connection issue.
I added some phone via the BAT tool yesterday and they will not register either (different location)
However they come back up if weplug them in on our subnet
Please Help this is Service Critical

 

[pndscm]

Sounds like a DHCP or a VLAN problem to me. You said you deleted the IP address and it didn't pick up a new one. Try statically defining an address on the phone. Check your DHCP server.
Look in the phone and see if it has a Voice VLAN. It gets this information from the Cisco switch it's plugged into via CDP. If it doesn't have one, check the switch configuration.

 

[Planetmaker]

there are both ok phones and downed phones on the same switchrebooting a switch does not resolve the problem

IP phone ip address can be pinged internally but not over the WAN hence the
cm list screen which indicates that there is a problem connecting to the call manager
which in this sites case is set to sub1>sub2 (cm2 + 3)
We are a local authority and a BT Routing Change done over the weekend could be affecting the traffic of the IP phones
that are down but why only some phones and why not any pc's?
All pc's ok. Whole site on one subnet no vlans
The BT change added virtual tables but didnt include any of the authorities sites and was done to create new secure routing group mainly for the authority's schools

 

[pndscm]

Look over the IP addressing on the phones. Is it possible the routing changes are only routing half the subnet, as in your subnet is a /23 but the routes are set for a /24? That would explain why you can ping internally but not across the WAN and why some devices are affected and some aren't.

 

[Planetmaker]

Checked that all address' appear very random...

 

[pndscm]

Not sure where to go from here. Back to BT I guess and see if they can help. Do you have SRST implimented and possibly that's why some phones are working and some aren't? The phones that are working, can they dial across the WAN?

 

[Planetmaker]

BT changed their routing tables back and now evrything is back to normal! WHich is good enough for me! Don't know yet know what is was that pronpted the bizarre atributes of the fault.
Thanks for the correspondance!

 

[pndscm]

Very weird but as long as it's working.

Good Luck