Hi,

It is not very clear to me how to handle serial forking scenarios with rtpengine where there are multiple RTP listeners attached to multiple network interfaces.

That is to say, given:

rtpengine ... -i net1/xxx.xxx.xxx.xxx -i net2/yyy.yyy.yyy.yyy

1. I attempt to reach SIP gateway 1 via net1, calling rtpengine_manage() in the process:

rtpengine_manage("replace-origin replace-session-connection ICE=remove direction=$avp(rtp_src) direction=$avp(rtp_dest)");

2. The call to gateway 1 fails, and I roll over to gateway 2, reached via net2, with dispatcher.

I have some logic that checks how $rd has changed and sets $avp(rtp_dest) accordingly in the dispatcher failure_route[].

3. In that failure_route[], I call:

rtpengine_manage("replace-origin replace-session-connection ICE=remove direction=$avp(rtp_src) direction=$avp(rtp_dest)");

4. When looking at the SDP for the INVITE on branch #2 going out to gateway 2, it does not appear to utilise media endpoint yyy.yyy.yyy.yyy, but rather continues to represent itself outwardly as xxx.xxx.xxx.xxx, even to gateway #2.

I can't figure out what I'm doing wrong here, and the 'rtpengine' documentation only has one mention of serial forking, in the context of the discussion of the 'via-branch' parameter. As far as I can tell, this is not relevant to my use-case; I am not concerned about deleting the whole call from rtpengine, but rather about updating the SDP offer consonantly with serial forking to gateway #2.

Any help would be deeply appreciated!

Thanks,

-- Alex