We have been working to get our Lumen trunk configured with FreePBX but are running into an issue with a busy signal not letting calls go through. We had to make a lot of changes to even get the trunk to register and I am not sure what could need changed in relation to this. The REGISTER messages are being sent and received on Lumen’s end, but they are receiving the internal IP of the PBX rather than the WAN IP we are NATing. Lumen says both the Contact and VIA headers are showing this internal address, but when I check our firewall and PBX settings all are showing the Public IP. Below are some additional details if it helps. What settings in the PBX could be causing this?
We receive Registrations from public IP 199.117.66.215 to Lumens SBC 65.149.36.151, but in there registration it tells us to send traffic back to a private non internet routable IP 172.18.10.29.
The contact and via header IP should be the public 199.117.66.215.
REGISTER sip:voip.centurylink.com:5100 SIP/2.0
Via: SIP/2.0/UDP 172.18.10.29:5060;rport;branch=z9hG4bKPKJAXSF7SD-4791-8215-1e56f155c187 🡨-------- should be PUBLIC IP
From: sip:[email protected];tag=98679afc1-29c9-4351-u76b-eb114d1532016
Call-ID: 6b55fa3a-a4b1-4e6c-ba5b-e29208fabbc6
CSeq: 12863 REGISTER
Contact: sip:USERNAME@172.18.10.29:5060;line=wfiufny 🡨-------- should be PUBLIC IP
Expires: 3600
Allow: OPTIONS, INVITE, ACK, BYE, CANCEL, UPDATE, PRACK, REGISTER, SUBSCRIBE, NOTIFY, PUBLISH, INFO, MESSAGE, REFER
Max-Forwards: 70
User-Agent: PBXact-17.0.19.23(21.5.0)
Content-Length: 0