We are managing few FreePBXs and other brands sip PBXs, each located locally in different branches of our business. Each of these remote PBXs are connected through a centralized one, a FreePBX release 14. We called this one our “Main” PBX.
The “Main” FreePBX is used as a sort of gateway, a centralized point to reach public networks using different Sip providers.
If one remote user wants to pass an outside call, it’s local PBX will pass the call to the “Main” one, and then the “Main” one will pass that outbound call to one of our SipTrunk providers depending of the destination of that call.
Now, everything (well, almost everything) is working fine, except for a specific scenario.
Problem : Let’s take Brandon as an example. Brandon is working in one of our remote branches, and that branch have it own PBX. Brandon is being in remote working for quite a long time now, and it’s office extensions is being forwarded to it’s home land lines. Brandon have a basic land line, without a call waiting service (Brandon is an old school type of guy).
If Brandon is receiving a 2nd consecutive call on his business extension, the 2nd caller will hear “You’re call cannot be completed as dialled, please try your call later”.
Why ? Our “Main” FreePBX intercepts the 486 busy coming back from Brandon’s land line provider, and ultimately our Sip Trunk provider, and plays the congestion message, instead of relaying the 486 busy up to Brandon’s office PBX. If we change the action of the Optional Destination on Congestion setting (outbound route) to something else, the PBX will execute that action on a busy call just as expected.
Is there anyways for us to bypass that Optional Destination on Congestion setting and let the FreePBX relay the 486 busy back to the downstream PBXs ?
“Main” FreePBX - 22.214.171.124
PBX Firmware: 12.7.6-2002-2.sng7
PBX Service Pack:126.96.36.199