[SR-Users] Solution for Invite retransmission

[Alex Balashov]

I would look to learn more about the ultimate cause of retransmissions
arriving beyond the life cycle of the transaction in Kamailio, as it
seems to possibly portend of a bigger problem.

However, if the issue is one of retransmissions arriving just beyond the
expiration of Kamailio's transaction lifetime holddown timers, you can
tweak those:

https://kamailio.org/docs/modules/5.3.x/modules/tm.html#tm.p.wt_timer

https://kamailio.org/docs/modules/5.3.x/modules/tm.html#tm.p.max_inv_lifetime

-- Alex

On Tue, May 12, 2020 at 05:15:15PM +0100, Duarte Rocha wrote:

> Greetings,
> 
> I have an issue where a client doesn't get the responses to the INVITE sent
> and as such keeps sending me retransmissions of the INVITE.
> 
> While the transaction is still up, Kamailio does its job. However, when the
> transaction is closed Kamailio processes the request again as a first
> request (Doing Routing and Dispatcher operations again).
> 
> In order to avoid the issue i've made the following code :
> 
>     // If it's the first INVITE
>  if( is_method("INVITE") && !has_totag() )
>  {
>   if(t_check_trans()) {
>             xnotice("TRANS - INVITE Retransmission");
>         }
>         else if ( is_known_dlg()) {
>             xerr("KamTAG: INVITE in dialog without To Tag ");
>             exit;
>         }
>     }
> 
> Is this a good solution and still compliant with the SIP rules?
> 
> Best Regards

> _______________________________________________
> Kamailio (SER) - Users Mailing List
> sr-users at lists.kamailio.org
> https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users


-- 
Alex Balashov | Principal | Evariste Systems LLC

Tel: +1-706-510-6800 / +1-800-250-5920 (toll-free) 
Web: http://www.evaristesys.com/, http://www.csrpswitch.com/