We are in the process of setting up lync voice and are experiencing an issue when users use the call back feature when trying to join audio of a conference. We have a pool of three front end servers, and a standalone mediation server. External
access with edge servers is also set up and working with a TMG reverse proxy.
If a user dials out from the lync client to an external PSTN number it works fine, no issue. But if the user is invited to a conference and then tries to have the conference call then back at that exact same number, when the user answers the phone,
the call immediately drops. Same goes if the call back number is internal as well, it rings and then the user picks and up and the call drops immediately. Every so often the call will stay connected, but it is very rare.
I've looked at logs on the mediation server but cannot see anything that sticks out, its sending the call to the pstn gateway like it should so it seems the problem lies with the front end servers and the conferenceing service. I've look at the s4,
sip and meetingmcu logs, this is what I see:
ms-diagnostics: 22;source="HHVAPPLYNCP03.domain.com";reason="Call failed to establish due to a media connectivity failure when both endpoints are internal";component="Audio Video Conferencing Server";CallerMediaDebugaudio="audio:ICEWarn=0x0,LocalSite=10.110.50.217:54566,LocalMR=206.83.12.34:59650,RemoteSite=10.110.50.147:51073,RemoteMR=206.83.12.34:58875,PortRange=49152:57500,LocalMRTCPPort=59650,RemoteMRTCPPort=58875,LocalLocation=2,RemoteLocation=2,FederationType=0"
I've confirmed that all those ports should be open. Not sure where to go from here. Any help is greatly appreciated. Thanks.
Rich
Ok, after some more troubleshooting it seems that this is only an issue with external calling that is routed through our edge server for external users. Inside our network, this call back feature works fine to any number, external or internal.
PSTN Calls ends immediately after connected ONLY when in conference, otherwise works fine
