There was no response from a trunk to an OPTION request sent by mediation server. Event ID (25051), LS Mediation Server RRS feed

  • Question

  • Hi All,

    I am getting above error since last 2 weeks in my lync server. My gateways (TA410 Yeastar) are frequently disconnecting from the mediation server after these errors and it is happening after every half hour and sometime earlier. These gateways were working fine on simple SIP trunk on UDP with Mobydick PABX but since I have transferred/integrated them to SFB 2015 server on tcp they are making problem and it seems they rebooting frequently after some time. All in/out calls are fine at the time when it is connected but once it is disconnected we can not make receive calls. I have tried many troubleshooting steps attaching and de-attaching the PSTN gateways from topology and used both direct IP and FQDN name but could not solve the issue.

    Is there any body who can help me on this? I appreciate the cooperation.

    Many Thanks   

    Sunday, July 2, 2017 12:49 PM

All replies

  • For the starter, your Gateway is not certified for Skype for Business. Not certified for either Lync 2010/2013 for that matter. There might be interop issues between platforms. You need a certified Gateway for Skype for Business (or, at least certified for Lync 2013.



    • Proposed as answer by Alice-Wang Monday, July 3, 2017 3:15 AM
    Monday, July 3, 2017 1:05 AM
  • Hi Thamara,

    Thanks a lot for your good response. But, I don't know why it is getting connected for sometime if it is not lync certified. Also, I have been in contact with Yeastar company to fix this issue and they know we are using this with skype for business 2015 but they did not tell as any limitation on these gateways for SFB?

    Also, is it possible if we disable OPTION request somehow being send to the gateways so it work properly?

    Please guide.

    Many Thanks

    Monday, July 3, 2017 6:34 AM
  • Nop. Skype only works with TCP and use OPTIONS for keep alive. Mediation Server sends OPTIONS to see if the Gateway in the other end is alive. There's no setting to disable that process. 5 consecutive failed response for OPTIONS requests from the Gateway, it marks the Gateway as "Down". Skype will not be sending any calls to that gateway afterwards.

    I recon there might be an issue with the response time for OPTIONS in Gateway. The certified ones are tested and optimized for this process. That's the reason (among others) not every gateway is compatible with Skype for Business. 


    Tuesday, July 4, 2017 2:11 AM