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    Assimetric Bandwidth usage WAN - LAN

    Scheduled Pinned Locked Moved Traffic Monitoring
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    • P Offline
      ploquets
      last edited by

      Hi!

      I'm dealing with a kind of problem that is new to me.

      We order a 20Mbps link with our local ISP and WAN traffic graph does show that they are delivering.

      As you can see here:

      But, when I go to LAN graph, is not symmetric  with WAN, which leads me to a problem to not know who are using our bandwidth.

      Then I even went to SSH and I tried to see via iftop with this command:

      iftop -m 20m -p -i re1
      

      re1 is our LAN interface

      But not a sign of this kind of traffic…
      Any other options to find out ?

      Thanks

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      • jimpJ Offline
        jimp Rebel Alliance Developer Netgate
        last edited by

        That would indicate it's the firewall itself using the bandwidth in some way. I'd look at packages you have installed. If you have squid, that is likely the culprit.

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        • A Offline
          Aburger
          last edited by

          Will NAT also cause this? I have the same issue that happens when I turn on NAT

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          • jimpJ Offline
            jimp Rebel Alliance Developer Netgate
            last edited by

            No.

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            • P Offline
              ploquets
              last edited by

              @Aburger:

              Will NAT also cause this? I have the same issue that happens when I turn on NAT

              YES, we do use Squid…. how to monitor traffic by IP ? inside Squid ?

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              • M Offline
                m4kin
                last edited by

                @jimp:

                No.

                My Squid is doing the same thing, he uses 90mb/s and the lan is using 20 mb/s.
                If I turn squid off… the consume goes down... and normalizes... if I turn it on... goes up again.

                Any tips of what to do?

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                • P Offline
                  ploquets
                  last edited by

                  @jimp:

                  That would indicate it's the firewall itself using the bandwidth in some way. I'd look at packages you have installed. If you have squid, that is likely the culprit.

                  But…. even using Squid, it should show traffic, from firewall (where squid is installed, going out thru the LAN interface) to the cliente.

                  Squid is caching content, but, traffic will also be send to the client host? no ?

                  This is really weird, unless the firewall itself is using, to make an update or something like that, it should show on traffic LAN interface graph.

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                  • jimpJ Offline
                    jimp Rebel Alliance Developer Netgate
                    last edited by

                    Squid can sometimes pull data back into its cache to revalidate and such without delivering that to clients. The specifics have fallen out of my brain but it's not unusual. Especially if you have squid caching things like windows updates or other large files.

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                    • M Offline
                      m4kin
                      last edited by

                      Even if I turn off the squid cache?

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                      • jimpJ Offline
                        jimp Rebel Alliance Developer Netgate
                        last edited by

                        That would be a question for the proxy board.

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                        • M Offline
                          m4kin
                          last edited by

                          With my squid turned off, just the traffic graph, continue showing this strange thing.;

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                          • C Offline
                            cmb
                            last edited by

                            You'll need to packet capture on WAN and see what that traffic is. Squid is a good guess where you're running it, but it could be any number of things, including traffic you're not soliciting (like a DoS of some sort).

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