Mediation server connected to three front end server in one pool but only one FE server reporting poor audio calls RRS feed

  • Question

  • We have three 3 front end server in one POOL. S1, S2, S3 they all connected to audiocode mediation server and mediation server connect to the PSTN.

    Front end server are enterprise edition when check the Skype SQL report I see only S2 having poor quality calls and drops packets between trunk-mediation and S2 but other two servers are preformation as expected.

    I did check to see if it’s related to load balancing but I see the three server have almost same call volumes and I did check the configuration for the 3 server and they are similar. I ran Get-CsPoolFabricState and test-csdatabase –LocalService and couldn’t find any issue. I am really running out of ideas why only one server in the pool having poor audio quantity and the rest of the front end are working fine.

    Forget to mention only calls generated outside the environment (outside calls using PSTN is having poor quality calls) and SQL reporting showing the Truck for the mediation server and S2 server having the highest poor quality calls in the environment.

    Any ideas?

    • Edited by Ramy Amer Tuesday, November 1, 2016 3:47 PM
    Tuesday, November 1, 2016 5:46 AM

All replies

  • The FE's are virtual or hardware. You should also check the network connection if only one server has a quality problem. But maybe this is the server which user use more pstn calling?

    regards Holger Technical Specialist UC

    Tuesday, November 1, 2016 6:30 AM
  • Hi Holger, Thank you for your reply. I worked with my network team and we couldn't see any network connection issue. should the PSTN calls be balanced by the load balancer? and I did check the call volume for the three servers and all have similar call volume. but if this is the case how could I balance the PSTN calls to all three servers in the POOL.

    I did check the server Lync server event viewer logs and this error keep coming up almost every two hours:

    Log Name:      Lync Server
    Source:        LS User Services
    Date:          11/1/2016 10:23:14 AM
    Event ID:      32263
    Task Category: (1006)
    Level:         Error
    Keywords:      Classic
    User:          N/A
    Computer:      XXX.XXX.com
    An error occurred while processing a batch of NotifyPipe replies from another front end. This resulted in the notification not being sent.

    Error code: 0xC3E93C2F(SIPPROXY_E_UNKNOWN_USER_OR_EPID), Error identifier: NotifySingle.Notify
    Cause: Possible issues with the other front end or with this front end.
    Ensure the front end is functioning correctly.
    Event Xml:
    <Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
        <Provider Name="LS User Services" />
        <EventID Qualifiers="50158">32263</EventID>
        <TimeCreated SystemTime="2016-11-01T02:23:14.000000000Z" />
        <Channel>Lync Server</Channel>
        <Security />

    Tuesday, November 1, 2016 2:24 PM
  • Hi Ramy, 

    You mentioned that there are drop in packets between the trunk-mediation and S2 , did you check with the NIC cards in the server , is that also update to date. Did you get a chance to restart the server and then monitor the behavior, Is the CPU/RAM also getting utilized  more compared to the other servers?

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

    Wednesday, November 2, 2016 8:05 AM
  • Hi Ramy,

    Welcome to our forum.

    Did you use SFB server 2015 or Lync server 2013?

    For this event, please update SFB server to the latest. There is a similar error in Lync server 2013:


    For poor quality call, please refer to the following steps for troubleshooting:

    1. Make sure all  SFB(Lync) server services are running, especially in  Mediation service
    2. Disable A/V and firewall on this specific FE server
    3. Restart this specific server or update it to the latest

    If there are any questions or issues, please be free to let me know.

    Best Regard,
    Jim Xu
    TechNet Community Support

    Please remember to mark the replies as an answers if they help and unmark them if they provide no help.
    If you have feedback for TechNet Subscriber Support, contact tnmff@microsoft.com.

    • Proposed as answer by jim-xu Monday, November 7, 2016 2:09 AM
    Wednesday, November 2, 2016 8:48 AM
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