Source note · Expressway business-to-business calling
Cisco's example DNS-zone search rule uses a negative-lookahead regex so calls to the organisation's own domain are never looked up on public DNS, while calls to other domains are.
Checked 2026-09-25
- Vendor
- Cisco
- Product
- Cisco Expressway
- Subsystem
- search rules
- Deployment
- on-premises
- Region
- not restricted
- Release range
- X14.0 guide
- Checked
- 2026-09-25
Sources
- Cisco Expressway-E and Expressway-C Basic Configuration Deployment Guide (X14.0) - Routing Configuration — Cisco Systems · tier 2 current vendor documentation · Routing Configuration: DNS zone search rule (priority 150, pattern excluding @example.com)
Cite this note
APA
WarmTransfer. (2026, September 25). Expressway business-to-business calling: source note expressway-b2b-calling-dns-rule-excludes-own-domain. WarmTransfer. https://warmtransfer.net/knowledge/claims/expressway-b2b-calling-dns-rule-excludes-own-domain
BibTeX
@misc{warmtransfer-claim-expressway-b2b-calling-dns-rule-excludes-own-domain,
title = {Expressway business-to-business calling: source note expressway-b2b-calling-dns-rule-excludes-own-domain},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/expressway-b2b-calling-dns-rule-excludes-own-domain},
note = {Source note expressway-b2b-calling-dns-rule-excludes-own-domain, checked 2026-09-25}
}