topic Re: Webex Calling - Flapping Trunk. in Webex Calling

Webex Calling - Flapping Trunk.

wvanderperre — Wed, 01 Oct 2025 12:47:33 GMT

We have identified an issue where the configuration for Registration-based trunks on the LGW is inadvertently triggering registration attempts based on number patterns in POTS dial-peers. This is causing trunk status flapping on the WxC side and impacting inbound/outbound calling.

This issue can lead to the establishment of two TCP-TLS sessions due to the registration attempts from POTS dial-peers. These attempts time out on the WxC side, resulting in the trunk status flapping. This problem was raised with Cisco TAC and appears to be a known issue. The solution was to apply the "no sip-register" command to all POTS dial-peers.

Requesting to update the relevant article to include information on the "no sip-register" command for POTS dial-peers.
https://help.webex.com/en-us/article/jr1i3r/Configure-Local-Gateway-on-Cisco-IOS-XE-for-Webex-Calling

Re: Webex Calling - Flapping Trunk.

Jonathan Schulenberg — Wed, 01 Oct 2025 20:38:54 GMT

Thanks for sharing but this is peer support; we can’t update the article either. The best approach is insisting that your TAC engineer open a documentation defect to get it fixed. The other option is providing feedback directly at the bottom of the help article.

Re: Webex Calling - Flapping Trunk.

wvanderperre — Fri, 03 Oct 2025 06:41:50 GMT

Hi Jonathan

Thanks for your feedback, I have provided feedback directly to the article as suggested.

It was actually TAC who instructed me to post this in the Community Support forum, but indeed I was also puzzled how a Community Support forum could update Cisco/Webex documentation.

To request an article update from Cisco, post your specific issue, the context of using the no sip-register command for POTS dial-peers, and the relevant Cisco IOS command reference link on the Community Support forums.
https://community.cisco.com

An expert will review and respond to your question, usually within one business day.