CUCM Virtual Core Reduction

[madhav.kumar.bhardwaj12]

We are currently using CUCM 9.1 template for 10,000 users which contain around 4 vCPU.But we have just deployed 3000 users. Can we reduced to 2 vCPU ? Both on PUB and SUB ?

[Chris Deren]

Downgrading VM is not officially supported, per:

• Removing virtual hardware resources (vCPU, vRAM, vDisk, etc.) is not supported (similar to moving from a more powerful server to a less powerful server, such as MCS 7845 ? MCS 7825). These migrations require backing up the application, reinstalling on a new OVA file, and and restoring the application.

http://www.cisco.com/c/dam/en/us/td/docs/voice_ip_comm/uc_system/virtualization/virtualization-software-requirements.html#resize_vm

So, only supported method would be to install new VM and restore from backup.