No inbound voice on SIP!



  • All, we have our Panasonic IP-PBX box sitting on our LAN. PFsense has a virtual public IP setup and ports are being forwarded to PBX. Now, we purchased few SIP trunks, configured on the system and we can receive the calls but can't hear the voice. The caller can hear me.

    PFsense is 2.1.5 and I also tried manual outbound NAT with no luck. Our supplier did ask us about SIP ALG but I have no clue how to disable it. Can you please advise? Thanks



  • Post your firewall rules and your NAT rules. Sounds like a port-forwarding issue.



  • Here is the inbound NAT, outbound NAT and firewall rules

    ![SAIP NAT inbound.png](/public/imported_attachments/1/SAIP NAT inbound.png)
    ![SAIP NAT inbound.png_thumb](/public/imported_attachments/1/SAIP NAT inbound.png_thumb)
    ![SAIP NAT outbound.png](/public/imported_attachments/1/SAIP NAT outbound.png)
    ![SAIP NAT outbound.png_thumb](/public/imported_attachments/1/SAIP NAT outbound.png_thumb)
    ![SIP Firewall rules.png](/public/imported_attachments/1/SIP Firewall rules.png)
    ![SIP Firewall rules.png_thumb](/public/imported_attachments/1/SIP Firewall rules.png_thumb)



  • The problem is most likely that your PBX is using its LAN IP address when it makes the SIP connection to your VoIP provider. The provider needs your public IP address, not the LAN IP address of the PBX.

    There are two ways to fix this:
    1. Have your PBX use the public IP address of your internet connection when it connects to your VoIP provider.
    2. Tell your VoIP provider to ignore the IP address in the SIP connection and use the IP address it sees on the other side of the incoming connection instead.



  • You have two WAN rules both duplicating a forward to port 35060. From what I can see on your NAT rule table, one of these should be 5060. Your NAT rule is doing a port mapping from 5060 to 35060 internally, but your corresponding WAN firewall rule isn't specifying the correct target port.