[SR-Users] issue with tm callbacks / premature cancel

[Andrew Pogrebennyk]

I've got stuck today trying to implement some sequential forking 
scenario. When the call comes destined to the local user, I'm trying to 
reach it sequentially through two alternative extensions. For each 
extension, I'm calling t_set_fr with a timeout of 15sec. They reply only 
180 and do not pick up the phone. After that the call should go to the 
"last resort" PSTN number. I'm calling then t_set_fr with a timeout of 
30sec. But immediately after sending INVITE to PSTN gw Kamailio 
generates cancel and sends 408 Request Timeout to the initial INVITE.

In the debug log I'm seeing this:

Aug  1 17:34:43 localhost /usr/local/sbin/kamailio[28488]: DEBUG: tm 
[t_hooks.c:288]: DBG: trans=0xb60f543c, callback type 1048576, id 0 entered
Aug  1 17:34:43 localhost /usr/local/sbin/kamailio[28488]: DEBUG: tm 
[t_reply.c:1634]: DEBUG: relay_reply: branch=1, save=1, relay=-1
Aug  1 17:34:43 localhost /usr/local/sbin/kamailio[28488]: DEBUG: tm 
[t_cancel.c:328]: DEBUG: cancel_branch: sending cancel...

Does it look like something familiar to you?

Kamailio version: 3.1.4
Config of tm module:
modparam("tm", "fr_timer", 20000)
modparam("tm", "fr_inv_timer", 120000)
modparam("tm", "restart_fr_on_each_reply", 1)

The rest of config is really simple, I can upload it somewhere if it's 
necessary.

-- 
Sincerely,
Andrew Pogrebennyk