I have been tasked to migrate one of my customer's IP telephony network from 192.168.11.0/24 IP addressing scheme to 172.27.72.0/23. My customer has deployed Cisco Call Manager and Cisco Unity Express. I just want to know what all things I should take care of, so this transition happens smoothly? I do not have much experience in handling such migrations, any help is highly appreciated.
One thing that I have learnt the hard way is migrating CUCM and UNITY. Make sure you change the ip address on the web interface by going to
SYSYTEM > SERVER
and changing the ip address to the new one (eg.172.27.72.1)
Then you need console access to them. If they are running virtually then this is a benefit. Login to each server an issue these commands:
set network gateway *<gateway>*
set network ip eth0 *<ip>* *<subnet mask>*
The server will then reboot and have the new IP you set. But make sure you change in on the WEB gui first to avoid being locked out!
I do not know about the SIP trunks that you have setup and how they have been configured.