When a device's IP address matches more than one Device Mobility Info subnet, Unified CM picks the subnet with the most bits in its mask (longest match rule); for example 9.9.8.2 matches 9.9.8.0/24 rather than 9.9.0.0/16.

Checked 2026-09-25

Vendor
Cisco
Product
Unified Communications Manager
Subsystem
device-mobility-info
Deployment
on-premises
Region
not restricted
Release range
15 and SUs
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). Unified CM Device Mobility: source note cucm-device-mobility-longest-match. WarmTransfer. https://warmtransfer.net/knowledge/claims/cucm-device-mobility-longest-match

BibTeX

@misc{warmtransfer-claim-cucm-device-mobility-longest-match,
  title  = {Unified CM Device Mobility: source note cucm-device-mobility-longest-match},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/cucm-device-mobility-longest-match},
  note   = {Source note cucm-device-mobility-longest-match, checked 2026-09-25}
}

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