For CUCM EndPointUnregistered alarms, Cisco advises matching the alarm's reason number, MAC address and timestamp, and looking up reason codes in the system error message reference.

Checked 2026-09-25

You must focus on the reason number of the error message, mac address and timestamp to match the alert.
Vendor
Cisco
Product
Unified Communications Manager
Subsystem
alarms
Deployment
on-premises
Region
not restricted
Release range
document dated 2023-07-28
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). SIP registration failures: source note sip-registration-failures-cucm-reason-number. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-registration-failures-cucm-reason-number

BibTeX

@misc{warmtransfer-claim-sip-registration-failures-cucm-reason-number,
  title  = {SIP registration failures: source note sip-registration-failures-cucm-reason-number},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sip-registration-failures-cucm-reason-number},
  note   = {Source note sip-registration-failures-cucm-reason-number, checked 2026-09-25}
}

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