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    arp: packet with unknown hardware format 0x00

    Scheduled Pinned Locked Moved General pfSense Questions
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    • Rapboy2019R
      Rapboy2019
      last edited by

      Hi guys I need help on how to get read of this.

      41e35ff8-748d-41b4-9e79-36e8c848940c-image.png

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      • GertjanG
        Gertjan
        last edited by

        hi,

        Locate the device that sends out rubbish, and locate a window. Throw the device through the window. If it's a Wifi device, put some effort into it.
        You already know it's the interface called 'em3'.

        No "help me" PM's please. Use the forum, the community will thank you.
        Edit : and where are the logs ??

        Rapboy2019R 1 Reply Last reply Reply Quote 0
        • Rapboy2019R
          Rapboy2019 @Gertjan
          last edited by

          @Gertjan I dont know where to start on how to trace it. do you have a guide or somthing that I can follow?

          arp.PNG

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          • GertjanG
            Gertjan
            last edited by

            Something or some one on that interface em3 is sending very broken Ethernet packets.
            Unhook the cable on your em3, or locate the device and have it repaired / removed.

            No "help me" PM's please. Use the forum, the community will thank you.
            Edit : and where are the logs ??

            Rapboy2019R 1 Reply Last reply Reply Quote 0
            • Rapboy2019R
              Rapboy2019 @Gertjan
              last edited by

              @Gertjan that em3 port is hooked to my LAN switch and then hooked to all of my Ubiquiti AP's for serving internet wirelessly to my neighbors. someone said that I can trace those whos causing this using a packet capture, but I don't know-how. I hope you can help me, sir, or is there a way to disable that from appearing on logs, cause even though it happens our internet is working fine.

              JKnottJ 1 Reply Last reply Reply Quote 0
              • GertjanG
                Gertjan
                last edited by Gertjan

                The issue isn't unknown.

                See, fro example : arp packet with unknown hardware format 0x00 received on

                The easy way : unhook one after the other the LAN's devices and check when the problem disappears.

                edit : ea6f850a-502a-4ca4-a68d-055863834cd6-image.png

                If you get some 'hits' consider raising the "Level of details".
                Before using the "packet capture" you should know what a packet is.
                Normally, I would prescribe a 3 hours crash course on Youtube. The excel in explaining what Internet (actually : Ethernet) is. This knowledge is very useful, as you are an Internet user, and you are running a firewall/routers, who's job is : handling those packets. Maybe it's time you should know what it handles ^^
                There is some good knew : it's not rocket science. Internet was build using the "keep it simple" concept. We just wanted something faster as the local post office services - and get fed up using the classic phone services.

                No "help me" PM's please. Use the forum, the community will thank you.
                Edit : and where are the logs ??

                1 Reply Last reply Reply Quote 1
                • JKnottJ
                  JKnott @Rapboy2019
                  last edited by

                  @Rapboy2019

                  After using Packet Capture, as described above, you can download the capture and view it with Wireshark to find the MAC address of the offending device.

                  PfSense running on Qotom mini PC
                  i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
                  UniFi AC-Lite access point

                  I haven't lost my mind. It's around here...somewhere...

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