Zoom sends a call to a backup SBC when the primary is marked down by OPTIONS keepalive failure or answers Zoom's INVITE with 403, 408, 480, 488, 500, 502, 503, 504 or 606; when a route group is exhausted it moves to SBCs in the backup region or data centre.

Checked 2026-09-25

Vendor
Zoom
Product
Zoom Phone
Subsystem
Failover routing
Deployment
multi-tenant
Region
not restricted
Release range
current as of 2026-09-25
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). Moving from Unified CM to Zoom Phone: source note cucm-to-zoom-phone-failover-triggers. WarmTransfer. https://warmtransfer.net/knowledge/claims/cucm-to-zoom-phone-failover-triggers

BibTeX

@misc{warmtransfer-claim-cucm-to-zoom-phone-failover-triggers,
  title  = {Moving from Unified CM to Zoom Phone: source note cucm-to-zoom-phone-failover-triggers},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/cucm-to-zoom-phone-failover-triggers},
  note   = {Source note cucm-to-zoom-phone-failover-triggers, checked 2026-09-25}
}

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