We have 3 call manager clusters all currently on CM 3.3(3) and use Intercluster Trunking to connect each for 4 digit dialing to the other locations. I would really like to upgrade the clusters to 4.1(3) but timing will not allow me to hit them all at once. My question is, if one or two clusters are upgraded will all work the same as when they were all on 3.3(3)? Has anyone done this?
Also, it could be an extended period of time (maybe 6 months) where 1 of the 3 clusters remains on 3.3(3)
Thank you very much.
There will be no issues. I have 3 clusters, 2 of which are 4.1(3) and one is 3.3(3) integrated via ICTs. Initially 2 of the clusters were on 3.3, then one was upgraded to 4.1, and recently a new one was added. I have not seen any issues.