Event 46009 An attempt to route to a gateway failed - 46046 as well RRS feed

  • Question

  • We are having sporadic problems with calls dropping and problems with Exchange UM disconnecting after 10 seconds.  One of the errors we notice on our FES Server is event 46009 for outbound calls.  Calls are working but for whatever reason every once in a while we get complaints from users being disconnected or not reaching our destination.  I have looked over many forum posts and troubleshooting guides.  Unfortunately I have not been able to figure this problem out.  Would anyone else have some ideas for us?

    Thank you,


    An attempt to route to a gateway failed.

    Could not route to Gateway ************ , the attempt failed with response code: 503 Service Unavailable (CallID: 0513ced6ab144cb3b3aebc9da614c964).
    Failure occurrences: 33, since 5/29/2017 4:32:11 PM.
    Cause: A gateway failed to respond to a request within allotted time or was unable to route the request due to some error.
    Check whether the specified gateway is up and is properly configured.

    Event 46046

    A call to a PSTN number failed due to non availability of gateways.
    Tuesday, May 30, 2017 4:19 PM

All replies

  • Hi SteveW0,

    Which product did you use for your PSTN gateway?

    Regarding this issue, please try to make sure your PSTN gateway has proper configuration, check the connection between your gateway and FE server.

    Based on my research, here is a similar case for your reference

    Hope this reply is helpful to you.


    Alice Wang

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    • Proposed as answer by danielategan Thursday, June 1, 2017 10:01 AM
    Wednesday, May 31, 2017 7:25 AM
  • Hello Alice,

    We use AudioCodes and we have reached out to them and they have confirmed the configuration is correct.  I will review the link again.  But so far we have not been able to track this down.

    We have opened up a ticket with our SIP provider as well.

    • Edited by SteveW0 Wednesday, May 31, 2017 8:43 PM
    Wednesday, May 31, 2017 8:42 PM
  • Assuming that your AudioCodes configuration is okay and no firewalls are blocking the communications ports between the FE servers and the Gateway, then you might want to look at any packet loss or latency between the two.

    In our case, the problem seems to happen when there is packet loss/latency between the Gateway and the FEs.

    Our workaround is to restart the Mediation Service "RTCMEDSRV". However, depending on your server's utilization, you may want to schedule this after hours, or you could also do a FailOver.


    Wednesday, May 15, 2019 6:04 PM