To change a Unified CM VM's vCPU, vRAM or vDisk, the Release 15 upgrade guide says to take a DRS backup, shut down the VM, then edit the settings in the vSphere Client, updating the reservation value to match the new release's specifications.

Checked 2026-09-25

Vendor
Cisco
Product
Unified Communications Manager
Subsystem
VM lifecycle
Deployment
on-premises
Region
not restricted
Release range
15 and SUs (VMware ESXi)
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). Unified CM virtualization and sizing: source note cucm-virtualization-sizing-resize-procedure-order. WarmTransfer. https://warmtransfer.net/knowledge/claims/cucm-virtualization-sizing-resize-procedure-order

BibTeX

@misc{warmtransfer-claim-cucm-virtualization-sizing-resize-procedure-order,
  title  = {Unified CM virtualization and sizing: source note cucm-virtualization-sizing-resize-procedure-order},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/cucm-virtualization-sizing-resize-procedure-order},
  note   = {Source note cucm-virtualization-sizing-resize-procedure-order, checked 2026-09-25}
}

Read in context