I have 800 number redirected from inbound route to misc extension which is a cell phone number. When I call out the 800 my cell rings but when I pick it up - nothing happens, the phone still rings. I dont see anything wrong in the call path. I think the FreePBX is not correctly bridging RTP.
I think the call needs to be answer first by PBX and PBX needs to initiate the call to the outside number.
I thought it should be easy, but is there any way to work that out?
In your router/firewall, forward the port range used for RTP to the PBX. Default is UDP ports 10000-20000.
Alternatively, play e.g. an announcement to the caller. The outbound media will then cause the firewall to pass audio from the incoming trunk, because it will appear as replies to what was sent out.
For example, Inbound Route -> Announcement -> Misc Destination. The Announcement could be a dummy such as 1/2 second of silence, or something like “please wait while your party is located”.
Thank You Stuart, looks like announcement works fine. So do you think I still have to open RTP ports to the firewall? I think I have them opened to 192.168.168.200 and my phones are in another subnet 192.168.180.0
Is there anything I need to add to the freepbx configuration?
Yup - progressinband=yes and make sure you are actually answering the call before you are routing it right back out - instead of a miscellaneous destination, send it to a Virtual Extension with Follow-Me to the outside number - I have seen the exact problem MANY times - it can’t see the far side answer, so it never completes the bridge - Virtual with Follow-Me works.
These solutions have different subtle characteristics. Port forwarding is required for remote extensions (other than via VPN) and for trunking providers that don’t proxy media. In this situation with forwarding, the caller will hear the same early media as if you called from a local extension. Usually, that’s good, but a ‘number has been changed’ announcement or an error message in a foreign language may be confusing.
With the announcement, the call is immediately answered, which could result in unwanted charges for the caller or interfere with operation of an automated system.
With progressinband, the caller hears fake ringback tone instead of any early media, which may cause him to miss a busy signal or relevant error message.
With follow me, you have the flexibility to select what the caller hears while the called party is being rung.
I have tested 800 with inbound route to the announcement and works great, my only concern is fallow me on the extension - same thing happening - cell is ringing, picking up the call and nothing …
I will be playing with advised progressinband=yes and making sure I have RTP ports open to FreePBX
Announcement forces the call to be answered - you could have an announcement with a ½ second of silence followed by the misc destination - or the follow me - either way, you have to answer the call and the announce does it - ring group would too.