Hi, 

Here's an example kamailio.cfg that uses record_route so in-dialog requests will go through the Kamailio proxy:
https://github.com/kamailio/kamailio/blob/master/etc/kamailio.cfg
There are many other example cfg files:
https://github.com/kamailio/kamailio/tree/master/misc/examples

Any server that wants to see the in-dialog messages needs to add itself to the record route list when receiving the initial INVITE for example. If a server is not in the list of record routes, then in-dialog requests will not be sent to the server. Headers that are most important in terms of routing are R-URI, Route, Record-Route, Contact, Via.

Via header is for routing responses, while Record-Route is for in-dialog requests.

I've put a few tips and some resources here about starting with Kamailio, which hopefully may help you a bit:
http://tao-communications-ltd.simplesite.com/447576389

Cheers,
Yufei

> Message: 7
> Date: Thu, 5 Nov 2020 12:26:16 +0200
> From: "Adrian Tabacioiu" <Adi.Tabacioiu at c-s.ro>
> To: sr-users at lists.kamailio.org
> Subject: [SR-Users] Proxy configuration that exit dialog afer INVITE
>         -> OK
> Message-ID: <7449102a9f3dbe38b6dba753d1cffcd8.squirrel at mail.c-s.ro>
> Content-Type: text/plain;charset=iso-8859-1
>
>
> Hello all,
>
> Am I new in the usage of kamailio, sorry if I ask somehow something simple
> or terribly wrong .
>
> I need to test a configuration of Kamailio which exit the dialog between
> UA after the first OK (that means it will not receive the following ACK,
> BYE).
>
> I understand that in theory this is possible in two configuration types:
> - no Record Route header
> - or stateless proxy
>
> First question:
> Am I correct with the choices above?
> Can I find example configuration for this two modes ?
>
> Question 2:
> two or more proxy should be inter-connected, removing the Record Route
> header would interfere with proxy routing ? (should not the "Via"
> information be sufficient?)
>
> Thank you in advance for help.
>
> Best regards,
> Adrian Tabacioiu
>