Cisco's IOS SIP MWI guide uses debug ccsip messages to observe the SUBSCRIBE/NOTIFY exchange and debug vpm all to observe visual MWI state changes on analog voice ports.

Checked 2026-09-25

Vendor
Cisco
Product
Cisco IOS voice gateways
Subsystem
SIP MWI debugging
Deployment
on-premises
Region
not restricted
Release range
Cisco IOS Release 15M&T
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). Message waiting indicator troubleshooting: source note mwi-troubleshooting-ios-debug. WarmTransfer. https://warmtransfer.net/knowledge/claims/mwi-troubleshooting-ios-debug

BibTeX

@misc{warmtransfer-claim-mwi-troubleshooting-ios-debug,
  title  = {Message waiting indicator troubleshooting: source note mwi-troubleshooting-ios-debug},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/mwi-troubleshooting-ios-debug},
  note   = {Source note mwi-troubleshooting-ios-debug, checked 2026-09-25}
}

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