Before switching versions on IM and Presence Service nodes, the Unified CM nodes must be switched first: the publisher, then the subscribers.

Checked 2026-09-24

Before you switch versions on the IM and Presence Service nodes, you must first switch the Unified Communications Manager nodes, starting with the publisher node and then the subscriber nodes.
Vendor
Cisco
Product
Unified Communications Manager
Subsystem
cluster upgrade order
Deployment
on-premises
Region
not restricted
Release range
Release 15 guide
Checked
2026-09-24

Sources

Cite this note

APA

WarmTransfer. (2026, September 24). Unified CM backup and upgrade: source note cucm-backup-upgrade-imp-switch-after-ucm. WarmTransfer. https://warmtransfer.net/knowledge/claims/cucm-backup-upgrade-imp-switch-after-ucm

BibTeX

@misc{warmtransfer-claim-cucm-backup-upgrade-imp-switch-after-ucm,
  title  = {Unified CM backup and upgrade: source note cucm-backup-upgrade-imp-switch-after-ucm},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/cucm-backup-upgrade-imp-switch-after-ucm},
  note   = {Source note cucm-backup-upgrade-imp-switch-after-ucm, checked 2026-09-24}
}

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