I have installed new switch but Phones are not registering . New switch voice subnet is deferent from CUCM severs subnet. I can see the phone is getting an IP from DHCP pool. and TFTP configuration in the DHCP pool is correct and I can ping to the CUCM from new switch. When I connect the phone to the other previously installed switches (Not by me) phone is registering. We use CUCM 7.0 and The phone type is 7911. any suggestions ?