On Cisco IOS, a fax protocol t38 setting on a VoIP dial-peer takes precedence over the global voice service voip setting.

Checked 2026-10-02

Vendor
Cisco
Product
Cisco IOS
Subsystem
fax protocol t38
Deployment
on-premises
Region
not restricted
Release range
IOS command reference dated 2007
Checked
2026-10-02

Sources

Cite this note

APA

WarmTransfer. (2026, October 2). Troubleshooting fax over IP failures: source note fax-over-ip-troubleshooting-dial-peer-over-global. WarmTransfer. https://warmtransfer.net/knowledge/claims/fax-over-ip-troubleshooting-dial-peer-over-global

BibTeX

@misc{warmtransfer-claim-fax-over-ip-troubleshooting-dial-peer-over-global,
  title  = {Troubleshooting fax over IP failures: source note fax-over-ip-troubleshooting-dial-peer-over-global},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/fax-over-ip-troubleshooting-dial-peer-over-global},
  note   = {Source note fax-over-ip-troubleshooting-dial-peer-over-global, checked 2026-10-02}
}

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