The Call Worked Until BYE: Debugging Dialog Routing in OpenSIPS and Drachtio
A call can establish, carry clean audio, and still fail at BYE when the dialog route set, backend affinity, or media cleanup path is wrong.
Record-Route
Record-Route Explained Why My BYE Took a Different Path
Initial SIP routing and in-dialog routing are different problems. Record-Route was the mechanism that made the proxy stay on the path after the call was established.