Troubleshoot Call Failures on TC Endpoints Registered to Cisco CallManager

Publisher

Cisco

URL

https://www.cisco.com/c/en/us/support/docs/collaboration-endpoints/telepresence-codec-c40/119207-ts-failures-end-ccm-00.html

Published

2015-07-23

Updated

unknown

Accessed

2026-09-25

HTTP status

200

License

Cisco website terms of use; no-redistribution; short excerpts and locators only

Source notes citing this source

• Cisco gives a common cause of SIP calls dropping at 15 minutes: the TCP timeout on firewalls or routers is shorter than the SIP session expires timer. It also says network devices that intercept refresh messages can cause the failure. in context
• To prove a session-refresh drop, Cisco says to collect SIP logs from both sides and check four things: the refresher role in the initial INVITE, that a re-INVITE or UPDATE goes out before half the interval, that Unified CM relays it to the far side, and that responses come back. in context
• The 2015 Cisco technote gives the CallManager (Unified CM) default SIP Session Expires Timer as 1800 seconds, which puts refreshes at about 900 seconds (15 minutes). in context

Cite this source record

APA

WarmTransfer. (2015, July 23). Troubleshoot Call Failures on TC Endpoints Registered to Cisco CallManager. WarmTransfer. https://warmtransfer.net/knowledge/sources/cisco-technote-119207-tc-ucm-call-failures

BibTeX

@misc{warmtransfer-cisco-technote-119207-tc-ucm-call-failures,
  title  = {Troubleshoot Call Failures on TC Endpoints Registered to Cisco CallManager},
  author = {{WarmTransfer}},
  year   = {2015},
  url    = {https://warmtransfer.net/knowledge/sources/cisco-technote-119207-tc-ucm-call-failures},
  note   = {Cisco, accessed 2026-09-25}
}