[asterisk-dev] Chan_pjsip keep_alive_interval

[Joshua Colp]

On Wed, Nov 9, 2016, at 01:25 PM, Ross Beer wrote:
> Hi,
> 
> 
> I'm investigating an issue where TLS connections close with a 'RST' after
> a random period of time.
> 
> 
> I can see that PJSIP sets 'PJSIP_TRANSPORT_IDLE_TIME=600', with the
> option in pjsip.conf 'keep_alive_internal' set, does this set both
> 'PJSIP_TCP_KEEP_ALIVE_INTERVAL' and 'PJSIP_TLS_KEEP_ALIVE_INTERVAL'?

The keep_alive_interval option doesn't set those in PJSIP. It controls
the interval at which code in Asterisk (not PJSIP) will send a
keepalive. There is no expectation that a response is received, as it
does not generate a SIP request itself. It allows runtime control
instead of compile time control.

> 
> 
> Does a keep-alive packet actually reset 'PJSIP_TRANSPORT_IDLE_TIME' if a
> response is received? If no response received, how many attempts are made
> before asterisk disconnects the session?

It does not reset the timer locally. Its purpose is to ensure the remote
side does not disconnect us for being idle. If we received a message
then our local idle timer would be reset.

-- 
Joshua Colp
Digium, Inc. | Senior Software Developer
445 Jan Davis Drive NW - Huntsville, AL 35806 - US
Check us out at: www.digium.com & www.asterisk.org