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    UDP packet drop - how to investigate

    Scheduled Pinned Locked Moved Firewalling
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    • N Offline
      nyit_dk
      last edited by

      Hi

      I have a fairly simple setup with a 100/100mbits fiber WAN and gigabit LAN, there is 5 users and they all have IP phones.
      The problem is that the IP phone calls often get dropped, the IP phone Company says it could be that the firewall drops UDP packets.
      There is no outbound rules
      There is no traffic shaping
      The avarage WAN load is below 5mbits with Peaks at ~30mbits
      The WAN quality is good with 0% packet loss

      How/where can i see if there is an UDP packet drop?

      Thanks

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      • N Offline
        Nullity
        last edited by

        @nyit_dk:

        Hi

        I have a fairly simple setup with a 100/100mbits fiber WAN and gigabit LAN, there is 5 users and they all have IP phones.
        The problem is that the IP phone calls often get dropped, the IP phone Company says it could be that the firewall drops UDP packets.
        There is no outbound rules
        There is no traffic shaping
        The avarage WAN load is below 5mbits with Peaks at ~30mbits
        The WAN quality is good with 0% packet loss

        How/where can i see if there is an UDP packet drop?

        Thanks

        You could run tcpdump on pfSense.

        Please correct any obvious misinformation in my posts.
        -Not a professional; an arrogant ignoramous.

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        • N Offline
          nelioromao
          last edited by

          Same Sample info about NAT and VOIP

          "NAT and VOIP don't speak very good"

          https://www.voip-info.org/wiki/view/NAT+and+VOIP
          http://kb.smartvox.co.uk/voip-sip/sip-nat-problem/

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          • chpalmerC Offline
            chpalmer
            last edited by

            @nyit_dk:

            The problem is that the IP phone calls often get dropped, the IP phone Company says it could be that the firewall drops UDP packets.
            There is no outbound rules
            Thanks

            Im betting you have outbound rules on your LAN interface that your phones connect to of some kind..  Can you enlighten us on what that rule set is?

            You may want to look at your firewall logs and state table (or use your packet capture) to identify the outbound server(s) that your phones are connecting to.  With those IP's then build firewall rules on your WAN interface allowing those servers UDP connections to your LAN net where your phones reside.

            Triggering snowflakes one by one..
            Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

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            • chpalmerC Offline
              chpalmer
              last edited by

              @5E:

              "NAT and VOIP don't speak very good"

              Thanks for the links.  ;)

              Ive mentioned here many times that VOIP was not originally designed to be behind NAT since it was purely a commercial venture..  NAT considerations were added later.

              These days it does not mean it cannot be made to work and most of the time it works without interaction. But there are a few of us with slightly off systems/providers that need a little help.  I have 6 different lines from 3 different servers coming into this location right now using the SIProxd package quite successfully.    :)

              Triggering snowflakes one by one..
              Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

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