Hello,

I am hoping someone may have seen this before. I am only finding old posts on the web. I am intermittently seeing calls fail with a 504 error in the event logs. I am also seeing on occasion the message that a gateway did not respond to an Options request. The events I see are 46009, 25051, 46046.

The failed calls and the 504 I attribute to Lync marking the trunk as down after 5 failed Options requests fail. The problem is that I cannot seem to find the 5 failed Options requests. I have used Wireshark and I have use OCSLogger. I am not sure if I have the correct options selected in OCSLogger to capture the traffic. I am using Mediation Server, Outbound Routing, S4 and Sip Stack. I have already been on support with my SIP vendor and they don't see the failed Options communications either.

My setup is a collocated Mediation Server/FE with an Edge server. The SIP trunk connects directly from the ISP to the server NIC. I am running the Aug CU on the Mediation/FE sever.

Any help would be greatly appreciated.

Are you not seeing the OPTIONS request at all or not seeing only responses to the OPTIONS request sent by the Mediation server?

Event ID 25051 appears if the Mediation server has sent the request but did not receive a response. Check if port 5060/5061 are open on your firewall.

Hi,

Please double check if the FE Server (Mediation Server) could be able to resolve the Lync Edge Pool FQDN. If not, add the DNS record in internal DNS, wait for replication, restart the Lync Server FE Server and then test the issue again.

Also, Please update Lync Server to the latest version.

Best Regards,
Eason Huang