A certificate-based trunk address must resolve from the public internet through a DNS A record or a DNS SRV record; an FQDN must resolve to an A record and not to a CNAME, an SRV service type must carry the prefix _sips._tcp, and Cisco prefers a time to live of 300 seconds or higher on all record types.

Checked 2026-09-15

Vendor
Cisco
Product
Webex Calling
Subsystem
Trunks
Deployment
not restricted
Region
not restricted
Release range
not restricted
Checked
2026-09-15

Sources

Cite this note

APA

WarmTransfer. (2026, September 15). Trunks route groups and dial plans in Control Hub: source note wxtrk-certificate-trunk-dns-record-rules. WarmTransfer. https://warmtransfer.net/knowledge/claims/wxtrk-certificate-trunk-dns-record-rules

BibTeX

@misc{warmtransfer-claim-wxtrk-certificate-trunk-dns-record-rules,
  title  = {Trunks route groups and dial plans in Control Hub: source note wxtrk-certificate-trunk-dns-record-rules},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/wxtrk-certificate-trunk-dns-record-rules},
  note   = {Source note wxtrk-certificate-trunk-dns-record-rules, checked 2026-09-15}
}

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