[SR-Users] Problem with Record-Route in Public to Private Network

[Carlos Escalona]

Hello! I wish everyone who reads this message a good day.

I would appreciate some guidance with the configuration of my Kamailio.

Initially, I have the following architecture:

Endpoints <----Public IP----> Kamailio (listen PrivateIP advertise
PublicIP) <----Private IP----> Asterisk

CONFIG:
https://gist.github.com/Carlos-Escalona94/3a289af05b05c69ae563ab29c9ec4710

In general, calls initiated from outside the system work perfectly, but I
have a problem with calls initiated from Asterisk.

According to what I was able to investigate and understand, the problem
arises from the fact that Kamailio uses the public IP for the entire
routing system that involves the Record-Route and Route Headers. This in
turn causes Asterisk to get lost trying to send messages outside of the
INITIAL INVITE transaction, for example, the ACK response to the 200 Ok
received from the Endpoint since it tries to use Kamailio's public IP to
which Asterisk doesn't have access.

I tried to force Asterisk to send all messages to Kamailio's private IP
regardless of their nature, but it doesn't seem like an appropriate
solution.

On the other hand, I tried to modify the architecture a bit so that it was
something similar to this:

Endpoints <---- Public IP----> Kamailio (listen PrivateIP:P1 advertise
PublicIP) <---- PrivateIP-----> Kamailio (listen PrivateIP:P2) <----
PrivateIP ----> Asterisk

CONFIG:
https://gist.github.com/Carlos-Escalona94/4d681bb189c6190941d291965e123889

It seems to me that this would solve the problem, but I have two doubts
about this architecture, the first is that I would like to know if there is
an easier way to solve the problem that I am not considering, and on the
other hand, I have not found a way to identify from which interface is
receiving the message to perform the routing properly.


Thanks for the attention.

-- 
*Esta mensagem pode conter informação confidencial ou privilegiada, sendo 
seu sigilo protegido por lei. Se você não for o destinatário ou a pessoa 
autorizada a receber esta mensagem, não pode usar, copiar ou divulgar as 
informações nela contidas ou tomar qualquer ação baseada nessas 
informações. Se você recebeu esta mensagem por engano, por favor, avise 
imediatamente ao remetente, respondendo o e-mail e em seguida apague-a. 
Agradecemos sua cooperação.
**
*
*This message may contain confidential or 
privileged information and its confidentiality is protected by law. If you 
are not the addressed or authorized person to receive this message, you 
must not use, copy, disclose or take any action based on it or any 
information herein. If you have received this message by mistake, please 
advise the sender immediately by replying the e-mail and then deleting it. 
Thank you for your cooperation.
*


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.kamailio.org/pipermail/sr-users/attachments/20220429/b5afbffe/attachment.htm>