Hello,

 

I’m using Kamailio as SIP proxy to receive INVITE packets, randomize A-number and then relay it to a certain gateway.

 

I noticed that a Via header is added to the INVITE sent by Kamailio to the gateway with 0.0.0.0 as address as shown below:

Via: SIP/2.0/UDP 0.0.0.0;branch=z9hG4bK2d97.61de75dd58fa7ca7450cc8b9b01db62f.0

 

As far as I know, the IP that should be used in the new added VIA header must be Kamailio IP, but it’s not the case here, knowing that Kamailio is not behind NAT.

I guess that you have listen global parameter with 0.0.0.0, you have to listen on the IP you want in Via or add advertise to listen with that IP.

Cheers,
Daniel

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Daniel-Constantin Mierla (@ asipto.com)
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