MOC is ringing but cannot pick up the call RRS feed

  • Question

  • Hi all,

    My call flow is like below:

    PBX agent ---> PBX --> DMG4060 --> Mediation Server --> OCS Server --> MOC

    I try to make call from PBX agent to MOC. However the test is not smoothly. I depict the symbol what I observed.

    1) PBX agent made a call to the MOC.

    2) When DMG received 180 Ringing message,MOC was also ringing concurrently.

    3) After MOC picked up the call, the call is disconnected immediately and DMG received 480 Temporarily Unavailable message.

    4) Also MOC showed “Call not connected or has ended” message.


    It is so strange.... MOC is ringing but the call cannot be picked up!!! I guess the case should be due to something wrong on Mediation Server or OCS Server.

    Please give me any advice!!!

    Friday, July 2, 2010 10:38 AM

All replies

  • This is commonly due to problems with the media traffic traversal.  The SIP communications are working but the media traffic is unable to be routed through.  There are a number of places this could be happening, starting with the media gateway.  I'd suggest running wireshark/netmon on the Mediation Server to look for the media traffic for starters.
    Jeff Schertz, PointBridge | MVP | MCITP: Enterprise Messaging | MCTS: OCS
    Friday, July 2, 2010 11:10 AM
  • Hi Jeff,

    Thanks for your suggestion. I have couple wireshark logs captured from the 2 NICs on the Mediation server. One NIC is connected to DMG4060 (media gateway) and another is connected to the Mediation Server. As you know, wireshark cannot capture the traffic from 2 NICs concurrently, so actually I captured them twice.

    Sorry I am not familiar with OCS media traffic, so I would like post them here and hope you expert can help me to analysis. How can I attach them here?

    Friday, July 2, 2010 1:27 PM
  • Do you have your mediation server's two NICs on the same subnet? If so, this is most likely causing your problem. Jeff as a good blog on the subject:





    Matt McGillen, PointBridge - https://blogs.pointbridge.com/Blogs/mcgillen_matt/default.aspx
    • Proposed as answer by mmcgille Friday, July 9, 2010 4:03 PM
    Friday, July 2, 2010 4:14 PM
  • Hi Matt,

    Thanks for your reply. Yes, the mediation server's two NICs are on same subnet. I will contact the user who maintains OCS (mediation server and OCS server) to seperatethe two NICs as different subnet. I will update here if I get the testing result.

    Saturday, July 3, 2010 4:11 AM
  • Hi..

    Can you check and see if bellow is ok..!

    1.       Routing path exist between Mediation server and MOC

    2.       No port blocking between Mediation Server and GW & Mediation Server and MOC.

    3.       Also just check and see if a call conference works between 1 PBX Clent+2 MOC, coz in this case MCU handles the media streams.

    I have almost the same setup works without a problem..



    Tuesday, July 6, 2010 11:34 AM
  • Hi,

    The inbound/outbound calls are established after I disabled one NIC on the Mediation Server. Thanks you all for the support!!!

    • Marked as answer by MA517 Friday, July 9, 2010 2:28 PM
    • Unmarked as answer by MA517 Friday, July 9, 2010 2:28 PM
    Friday, July 9, 2010 2:28 PM