Dynamic inbound-to-outbound routing to a different SIP trunk (V20)

[aman-pandey]

Hi team,

I'm using Telnyx's API to originate calls into our 3CX (V20, self-hosted). I need these inbound calls to route back out through a different SIP trunk to a phone number that's different each time — not a fixed number.

I've tried using %DialedNum% and %CalledNum% in an Inbound Rule and in a trunk's Default Route ("Forward to Outside Number"), but both get treated as literal text instead of the actual dialed number, and the call fails. Is there a supported way to do this, or do I need to use DISA or a Call Processing Script instead?

 

[KyriacosS_3CX]

Can you explain what the aim is in a bit more detail? Are the Outgoing numbers matched 1-to-1 with the Incoming (per-extension forwarding), or do they change over time (CFD or some other automation)?