Upgrade IM & P to 12.5 keeping CUCM in 11.5

[SMK91]

Hi Guys,

We have already installed both CUCM and IM & P version 11.5. But IM & P still not in a production environment.  In meantime, we have decided to upgrade both CUCM and IM &  P to version 12.5.

My question is can we upgrade IM & P first to version 12.5 while keeping CUCM 11.5? Is there any compatibility issue?

[Jaime Valencia · Accepted solution]

https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/compat/12_x/cucm_b_compatibility-matrix-cucm-imp-125x.html#reference_DADD7740A3A71B4C89EFB65C8154B9BA

[Roger Kallberg · Accepted solution]

No you cannot. In versions prior to 12 the version numbers for CM and IM&P have to match the five first digits, from version 12 this changes to the first three digits.