Hello,

 

the tcp_reuse port setting is mainly using if Kamailio is acting as UAC, and needs an existing connection to be able to re-use something.

 

The RFC specify how its normally should done from a client :

 

18.1.1 Sending Requests
 
   [..]

   For reliable transports, the response is normally sent on the

   connection on which the request was received.  Therefore, the client

   transport MUST be prepared to receive the response on the same

   connection used to send the request.  Under error conditions, the

   server may attempt to open a new connection to send the response.  To

   handle this case, the transport layer MUST also be prepared to

   receive an incoming connection on the source IP address from which

   the request was sent and port number in the "sent-by" field.[..]

 

Not sure what the other side is, but maybe you can discuss that with them.

 

Cheers,

 

Henning

 

--

Henning Westerholt – https://skalatan.de/blog/

Kamailio services – https://gilawa.com

 

From: Maarten Ureel <maarten@youreal.eu>
Sent: Wednesday, August 3, 2022 2:09 PM
To: Henning Westerholt <hw@gilawa.com>; Kamailio (SER) - Users Mailing List <sr-users@lists.kamailio.org>
Subject: RE: set source port of TCP socket in Contact header

 

I tried the tcp_reuse_port but it doesn’t seem to change the source port. It’s always random indeed as you say.

See also screenshot from sngrep: https://i.imgur.com/gp7WQ1C.png

 

The problem is that, further down the call, the other party sends the BYE to the port that is specified in the Contact header, so e.g. in the screenshot I would like to put 48952 in the Contact header – or have it always be 5060 indeed.

 

 

Van: Henning Westerholt <hw@gilawa.com>
Verzonden: woensdag 3 augustus 2022 13:28
Aan: Kamailio (SER) - Users Mailing List <sr-users@lists.kamailio.org>
CC: Maarten Ureel <maarten@youreal.eu>
Onderwerp: RE: set source port of TCP socket in Contact header

 

Hello,

 

Not sure if I completely understand the issue.

Kamailio will either use a random source port, or the port 5060 if you specify the tcp_reuse_port core configuration.

 

Cheers,

 

Henning

 

--

Henning Westerholt – https://skalatan.de/blog/

Kamailio services – https://gilawa.com

 

From: sr-users <sr-users-bounces@lists.kamailio.org> On Behalf Of Maarten Ureel
Sent: Tuesday, August 2, 2022 4:53 PM
To: sr-users@lists.kamailio.org
Subject: [SR-Users] set source port of TCP socket in Contact header

 

Hello

 

I want to set the correct source port in an outgoing message over TCP. Is it possible? I can’t find a pseudo-variable for this.

Currently we have no port number in the contact header, and the other party is sending their BYE to port 5060 instead of to the source port from which the outgoing TCP connection was made.

 

 

 

Regards

Maarten