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_lifetim...

-- 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@lists.kamailio.org https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users

Hello Alex and Daniel,

Thank you for your answers.

This happened when a client had some network problems and couldn't received my packets. The problem is that after some time and the transaction is dead,since Kamailio does a new dispatcher, my accounting system counts this as two calls and that's the behaviour i want to avoid. Since in this case the client has network issues and won't probably get the SIP replies, i don't think raising the timers will be very helpfull.

Also, i already use Dialog module for other functionalities so i don't think there's a need to go to hash tables.

Thanks for the help.

A terça, 12/05/2020, 17:15, Duarte Rocha duarterocha91@gmail.com escreveu:

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