Porting to SIP Trunk Broke Lync Conference

[hauchinango]

Last night, we ported over our DID's from legacy ISDN/PRI to SIP trunks from PSTN. After doing so, our conference bridge from UCM to Lync will not connect. I suspect an incompatibility with the SIP trunks or profiles but cannot determine the cause. I am able to dial the internal route pattern to reach Lync successfully, but cannot connect from outside our cluster.

Previous call flow: PSTN>PRI>RouterH323>RoutePattern>SIPTrunk>LyncServer
Current call flow: PSTN>TelcoSIPTrunk>CUBE>SIPTrunk>RoutePattern>SIPTrunk>LyncServer

I see the call trying to connect in debugs but it never gets past the connecting status. 

Any suggestions? 

[Rajan]

What is the error you are getting ? COuld you share the debugs from CUBE to check.

[hauchinango]

CM traces show error code 400/Bad Request.

[hauchinango]

The bad request is coming from Lync:

55957829.001 |07:24:23.372 |AppInfo  |SIPTcp - wait_SdlSPISignal: Outgoing SIP TCP message to 10.10.10.1 on port 19918 index 382370

SIP/2.0 400 Bad Request

The 10.10.10.1 is the loopback on my CUBE router.  I do not have that defined as a PSTN gateway in Lync, rather only my UCM servers are defined as gateways in Lync.  Would I need to add the CUBE?  I haven't been able to find docs to clarify this.

Thanks

[Adam Pawlowski]

Lync wants full +E164, is the calling number still formatted right in your flow ?

[hauchinango]

Yes,we are sending full +e164

[TONY SMITH]

Let's see the actual debugs.  We can't really comment on an error message out of context, especially a generic one.  I think we want to see the SIP messages between CUCM and Lync.

[hauchinango · Accepted solution]

After much head banging and web sluething, I Was able to get this working finally by changing a setting in the SIP profile for the trunk.  I set the "SIP Rel1xx Options" to "Send PRACK if 1xx Contains SDP"