CUCM Upgrade without upgrading IP Phones Firmware

[shacharalon7]

Hi Guys,

Is there a way to upgrade a CUCM Cluster (2 Nodes) without forcing the IP Phones to upgrade their firmware versions but keep the one installed pre upgrade ?

Thanks,

#cucm #upgrade #ip hones

[jason-mcgee]

Only if the older firmware will work on the new version of CUCM. If that is the case, and you should be able to find this out in the compatibility matrix, then you will need to install the publisher, copy the old version of the firmware and place it in the device defaults as well as make sure it is on the tftp server prior to pointing any phones to the new call manager. One other possibility is if the firmware is maxed out on upgrades for the particular model you are referring to and if the phone is not deprecated on the version you are moving to, if so you will already be at the latest version as no other revisions were made. An example of this is the 7975 and CUCM 11.x to 12.5. That one was revised as far as it will go on CUCM 11.x but it will run on 12.5 and will be deprecated on 14.x I personally didn't try to run the firmware for CUCM 10.5.2 on 11.5 though, but that may work as well. 

Which phone models are you looking to do this on and which version CUCM are you moving from and which version are you moving to?

[Chris Deren · Accepted solution]

Here is how handle this as many larger customers ask for this:

1. De-activate TFTP service on all TFTP nodes

2. Export device defaults from BAT

3. Upgrade CUCM Pub

4. Export device defaults after upgrade (this is just to give you snapshot of new default firmware)

5. Import exported device defaults from step 2, this will revert all of the firmwares back to what they were

6. upgrade remaining CUCM nodes

7. When TFTP nodes are activated and dbreplication is good between all nodes re-activate TFTP services

[shacharalon7]

Thank you!

[saravanan.psk]

Hello Chris,

Thanks for explaining.

When we need to switchover the CUCM version from inactive to active? After step 7.