External Users Cannot Make Calls Through Lync Mediation Servers But Can Through OCS 2007r2 RRS feed

  • Question

  • Hey,

    We have migrated from OCS 2007 r2 to Lync 2010. We have a Lync edge server but still have 2 legacy 2007r2 mediation servers.

    When connected externally calls to the PSTN using a Lync mediation server ring, but once answered fail to connect. I get "Connecting" then eventually the call drops.

    If I make the same call using a leagacy mediation server the call connects as expected.

    I have the firewall on all servers disabled currently. I expect that our external firewall is setup correctly as calls work through the legacy mediation servers.

    I know in OCS 2007r2 you need to specificy the next hop and edge server, but I cannot find these settings in Lync.




    23; reason="Call failed to establish due to a media connectivity failure when one endpoint is internal and the other is remote"; CallerMediaDebug="audio:ICEWarn=0x2e0,LocalSite=xxx.xxx.xxx.xxx:12544,LocalMR=xxx.xxx.xxx.xxx:57647,RemoteSite=xxx.xxx.xxx.xxx:55892,PortRange=1025:65000,LocalMRTCPPort=57647,LocalLocation=1,RemoteLocation=2,FederationType=0"

    Call failed to establish due to a media connectivity failure when one endpoint is internal and the other is remote
    The call failed to connect because a media path could not be established between an internal endpoint and a remote endpoint. This failure can be caused by network performance issues affecting the endpoints or an endpoint being unable to use the A/V Edge Server. Correlation of such failures with individual networks, endpoints or A/V Edge Server can indicate potential deployment issues.



    Any ideas would be great!




    Friday, December 10, 2010 11:37 PM


All replies

  • Hey,


    I have the same issue, did you find a solution ?



    Monday, December 27, 2010 10:49 AM
  • Hi Andrew,

    Please double check the A\V edge interface configuration and make sure that you have open port 50000 to 59999 from the firewall. There is a next hop configuration in LYNC Edge pool configuration in topology builder.

    Wednesday, December 29, 2010 5:27 PM
  • Andrew,

    Did you find a solution for this issue? I'm having the same problem.

    Thanks a lot for any help.


    Alexandru Zamfir Probitas International Bucharest, ROMANIA.
    Friday, February 18, 2011 8:59 PM
  • I still havent got this 100% working. Currently we are still using a leacy Mediation Server.


    Sunday, February 20, 2011 8:15 PM
  • Andrew by any change are you trying to use a Lync collocated mediation server?
    Alexandru Zamfir Probitas International Bucharest, ROMANIA.
    Monday, February 21, 2011 8:38 PM
  • I got the final part of this puzzle sorted today.



    I also had a correctly set Lync as the next hop server.



    Monday, February 21, 2011 9:02 PM
  • Glad to hear that all is working now. Can you please tell me if your Lync Mediation is collocated or not?



    Alexandru Zamfir Probitas International Bucharest, ROMANIA.
    Tuesday, February 22, 2011 7:43 AM
  • Hey,

    Yes the mediation server is co-located on the front end. 

    When I said I set the next hop server, this was on the legacy mediation server. This had to be set to point to the Lync pool.

    Now that incoming calls to the Lync mediation server are working correctly I will decommission the legacy one.

    Hope that helps.



    Tuesday, February 22, 2011 6:58 PM
  • I have just realised what while this works for calls to users it doesn't for Un-assigned numbers.

    This particular un-assigned number is set to transfer to a response group. The transfer fails with this error:

    RTCC/ Response_Group_Service Announcement_Service
    Diagnostic header:
    26005; reason="The Response Group application was unable to transfer the call to the configured destination and no fallback exists."

    Again I can see in the logs that the number hasnt been normalised, so I suspect that this is the issue again.

    How can I make sure Lync is normalising all incoming calls so it can match to a user, response group or un-assigned number? This was never a problem in OCS 200r2 - has something change in Lync?

    I realise I could do this at the gateway, but I am trying to avoid this as the Telco has to do it and will require a called to be logged.

    Help would be very appreciated.


    Wednesday, February 23, 2011 8:16 PM