Recently, I had setup CCE 2.0 for one of my customer and PSTN call to SFB is ok. However PSTN call to SFB Client forward to Voice Mail failed. Using the PSTN phone, I dialled the digit of the SFB Client, it would forward to the online voice mail server through CCE, after 10 seconds call disconnect without any audio. It seems no INVITE to the voicemail server due to the ICES error below.
The external firewall is set to allow port range 50,000 to 59,999. Is this range enough for RTP when connecting to voice mail servers like: apac.voicemail.services.skypeforbusiness.com, noam.voicemail.services.skypeforbusiness.com
Please help.
Thank you.
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ms-diagnostics: 23;source="Med-045837.sfb-ccedomain.local";reason="Call failed to establish due to a media connectivity failure when one endpoint is internal and the other is remote";component="MediationServer";Exception="Proxy side ICE connectivity check failed.";ICEWarningFlags="BaseAddress="v.v.v.v:53976";LocalSite="z.z.z.z:57213";RemoteSite="w.w.w.w:6328";MediaEpBlob="ICEWarn=0x40003a0,ICEWarnEx=0x0,LocalMR=x,x,x,x:51195,RemoteMR=y.y.y.y:58445,PortRange=49152:57500,LocalMRTCPPort=50582,RemoteMRTCPPort=58445,LocalLocation=2,RemoteLocation=1,FederationType=0,StunVer=0,CsntRqOut=0,CsntRqIn=0,CsntRspOut=0,CsntRspIn=0,Interfaces=0x2,BaseInterface=0x2,IceRole=1,RtpRtcpMux=0,AllocationTimeInMs=210,FirstHopRTTInMs=1,TransportBytesSent=19595,TransportPktsSent=595,IceConnCheckStatus=5,PrelimConnChecksSucceeded=0,IceInitTS=3710720554760,ContactSrvMs=178,AllocFinMs=234,FinalAnsRcvMs=2299,ReinviteSntMs=12725,BlobGenTime=3710720567485,MediaDllVersion=6.0.8953.265,BlobVer=1""
ms-diagnostics-public: 23;reason="Call failed to establish due to a media connectivity failure when one endpoint is internal and the other is remote";component="MediationServer";Exception="Proxy side ICE connectivity check failed."
