Hi all!
I plan to execute an upgrade of CUCM of a cluster from version 7.1.5 (three MCS7835 servers) on version 9.1 (on two UCS C260 TRC servers).
On the basis of documentation and requirements of the Customer to breaks in telephony service I prepared the plan of carrying out procedure of an upgrade:
1. Refresh upgrade Publisher MCS-server from 7.1.5 to 9.1 (unsupported for 9.1) and switch to 9.1.
2. Perform DRS-backup from Publisher-server
3. Switch to inactive Partition (return Publisher to 7.1.5)
3. Install the new Cisco Unified Communications Manager version on your new supported first node in isolated LAN with same ip-addresses as old CUCM)
4. Install license to new Cisco Unified Communications Manager
5. Restore first node of new Cisco Unified Communications Manager from DRS-backup
6. Install two new subscribers on isolated LAN and add additional subscribers to cluster
7. Check all services at new CUCM cluster.
8. Disconnect old CUCM cluster and simultaneously connect new cluster to LAN
The main idea of such plan of updating - to keep telephony service on an old cluster of CUCM until readiness of a new cluster and to check a new cluster before introduction in operation.
I will be grateful if someone finds a little time to check mistakes in my plan.
