Problem with NAT

Hello i´m using FreePBX and today i upgraded because i thought it could solve my problem.

I have 15 chan_sip extensions (all outside). They register well, can make and receive calls but when they make a call it hanges up in a few seconds.

This is the log for that call

[2016-04-25 12:49:45] WARNING[2457] chan_sip.c: Retransmission timeout reached on transmission a5c42c9c0c73df0d for seqno 1731670581 (Critical Response) – See …
Packet timed out after 6400ms with no response
[2016-04-25 12:49:45] WARNING[2457] chan_sip.c: Hanging up call a5c42c9c0c73df0d - no reply to our critical packet (see …).

In the same place i have another PBX (Yeastar) and when i call from this one to FreePBX everything is OK.


I think this is a network issue from your endpoints. They are soft phones? Do you have any firewall or protection on computers?

I have both softphones and ATA gateways

Did you look at the “See …” links the error messages gave you?

Hey @radzero

Check the Astersik Sip settings tab and Check the NAT settings.
Also chek things in CHAN sip.

Sounds like the RTP stuff is not flowing thru.
Could also be firewall issues.