Skype call failed when one user is in internal network and the other is at external network RRS feed

  • Question

  • Hi everyone,

    Error message "call failed to due to network issue"

    Call get connected if both users are on internet network.

    Can someone give hint on where should i start to troubleshoot?

    Monday, March 20, 2017 9:27 AM

All replies

  • Hi  Tony , 

    I assume that you are trying to troubleshoot a call between two endpoints , one internal and one connected through the edge server ( External) . you need to be  checking again the edge configuration to   see if it has the corrrect ip address  assigned as per topology , whether the routing is correct form external to internal and internal interface to the FE servers.

    You should also check your Edge Network Configuration.

    Dns should point to the external dns Server. Default Gateway should point to the External router.

    All internal subnet should be configured through persisten routes.

    All internal Lync server should be added to the host file.

    Please check also, taht you don't have tls Errors on the eventlog for all Lync Server.

    Linus || Please mark posts as answers/helpful if it answers your question.

    Monday, March 20, 2017 11:34 AM
  • Hi Linus,

    Thank you for your reply. You are correct. I am troubleshooting a call between two endpoints , one internal and one connected through the edge serve

    I did a check on the topology and our firewall(NAT) and found no error. The IPs are defined correctly. Persistent routes are added.

    Question - How do I Check this -> All internal Lync server should be added to the host file.

    error that i found in UccApiLog.

    ms-client-diagnostics: 23; reason="Call failed to establish due to a media connectivity failure when one endpoint is internal and the other is remote";UserType="Callee";MediaType="audio";MediaChanBlob="NetworkErr=no error,ErrTime=0,RTPSeq=0,SeqDelta=0,RTPTime=0,RTCPTime=0,TransptRecvErr=0x0,RecvErrTime=0,TransptSendErr=0x0,SendErrTime=0,InterfacesStall=0x0,InterfacesConnCheck=0x0,MediaTimeout=0,BlobVer=1";BaseAddress="";LocalSite="";NetworkName="xxxx";RemoteSite="";MediaEpBlob="ICEWarn=0x2b,ICEWarnEx=0x1,LocalMR=,PortRange=20000:20039,LocalLocation=2,RemoteLocation=1,FederationType=0,StunVer=0,CsntRqOut=0,CsntRqIn=0,CsntRspOut=0,CsntRspIn=0,Interfaces=0x4,BaseInterface=0x4,IceRole=1,RtpRtcpMux=1,AllocationTimeInMs=3869,FirstHopRTTInMs=0,TransportBytesSent=2842,TransportPktsSent=98,IceConnCheckStatus=5,PrelimConnChecksSucceeded=0,IceInitTS=3698988902088,ContactSrvMs=3884,AllocFinMs=3886,PrelimAnsRcvMs=8565,FinalAnsRcvMs=10743,ReinviteSntMs=21868,BlobGenTime=3698988924057,MediaDllVersion=6.0.8953.259,BlobVer=1";MediaMgrBlob="MrDnsE=GAHSfBAV.xxx,MrResE=0,MrErrE=11001,MrBgnE=36989889020867552,MrEndE=36989889020871088,MrDnsI=AUGAHITDSVR0201.xxx,MrResI=1,MrErrI=0,MrBgnI=36989889020838224,MrEndI=36989889020843008,MrDnsCacheReadAttempt=0,BlobVer=1"

    Any more clue to check?

    Tuesday, March 21, 2017 2:03 AM
  • Hi Tony,

    Did the issue happen to specific client or all clients had this issue?

    If the issue just appeared to the specific SFB client, it may be a client issue, we suggest you delete SFB cache files and install the latest update for your SFB client then test again.

    Moreover, please try the following tips:
    1. Try to telnet to port 443 port on Edge Server.
    2. Please make sure all required ports on Edge Server are allowed:
    Here is a good article about Lync server ports and audio/media negotiation for you to understand the media connection more clearly. You can refer to “One User External and One User Internal” section

    Note: Microsoft is providing this information as a convenience to you. The sites are not controlled by Microsoft. Microsoft cannot make any representations regarding the quality, safety, or suitability of any software or information found there. Please make sure that you completely understand the risk before retrieving any suggestions from the above link.


    Alice Wang

    Please remember to mark the replies as answers if they help.
    If you have feedback for TechNet Subscriber Support, contact tnmff@microsoft.com.

    • Proposed as answer by Alice-Wang Friday, March 24, 2017 8:44 AM
    Tuesday, March 21, 2017 6:17 AM