Hi,
We’re running into a critical issue with BIB-based recording in CUCM 12.5.
We use a SIP-integrated recording application. On some calls, only one leg is recorded properly. The other results in a 0KB file.
After reviewing the RTMT and SIP handler logs, the issue seems to be with how CUCM handles SDP negotiation for the two media streams it forks to the recording server.
Here’s what the logs show:
The call signaling looks fine. SIP setup via our trunk (SGS-Middleware-Trunk) works as expected.
CUCM activates the BIB forking mechanism as it should. This should send two RTP streams, one for each party in the call, to our recorder.
The recording server is at 10.10.200.90. This IP appears correctly in the logs for the working stream.
The problem starts with the second recording leg. CUCM sends the SDP for this leg with the wrong destination.
Instead of targeting 10.10.200.90, CUCM sets c=IN IP4 10.10.200.48—which is the IP address of the Cisco IP Phone involved in the call which is a 8841 IP Phone.
This causes CUCM to send that RTP stream to the phone, not the recording server. Which is the reason whey we are getting an empty recording file for that leg.
The issue isn’t with our application failing to receive the stream. It’s that CUCM is directing one of the media streams to the wrong IP in its SDP offer.
The recording profile is for sure configured to use the correct recording server IP. SIP Profiles and Region settings are all configured on default for lab testing. But the logs clearly point to CUCM mishandling the media path setup during the recording process.
I’ve attached the app log files as well as the RTMT trace. Any guidance on what might cause CUCM to insert the phone’s IP instead of the recorder’s in one of the BIB streams would be very helpful.
Thanks
