Sip Timer T1 and B?

So, I was searching for something else today and stumbled across this link, suggesting that admins of busy Asterisk systems consider tuning these two settings “

So, the questions are now “Where do I find these settings in FreePBX?” and “Is there a reason I should just leave well-enough alone?”

I didn’t find these settings in the Web interface, nor did I find them in /etc/asterisk anywhere, and before I go and start adding anything willy nilly (it is a busy system), I thought I would ask.


Are you having a specific issue that you need to adjust the timers?

You can access any channel variable in the SIP settings module. Are you using chan_sip or PJSIP?

No particular issue, but given the content of the article, I was considering experimenting on a test system. With ~60 concurrent incoming SIP channels and the corresponding PBX–>Device SIP channels, I figured it might be worth exploring.

Would I need to add a custom entry for the timers, or is there a pre-populated field somewhere that I missed?


No, you would have to use the “other sip settings field” to access these counters.

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This topic is a bit old, but I would like to jump in. Is it possible to edit the timer_t1 and timer_b asterisk settings for pjsip on freepbx? I attempted to edit the pjsip_custom.conf in the config editor, but the changes don’t show in the pjsip settings when I restart asterisk. The issue I have is related to extensions floating back and forth from reachable and unreachable. I think this issue is related to the t1 timer that is expecting a response within 500. I have some extensions that have a slow initial connection response.