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    Every second a new firewall LAN message

    Scheduled Pinned Locked Moved Firewalling
    21 Posts 7 Posters 2.8k Views
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    • johnpozJ
      johnpoz LAYER 8 Global Moderator
      last edited by

      this is a device

      a4:93:4c:fd:ce:41

      Yes I show a4:93:4c as cisco..  so you need it track down that device sending the pings to this 1.2.3.4 so you can figure out why its sending them

      where exactly did you do the sniff?  Is there another router between the sender and pfsense?

      An intelligent man is sometimes forced to be drunk to spend time with his fools
      If you get confused: Listen to the Music Play
      Please don't Chat/PM me for help, unless mod related
      SG-4860 24.11 | Lab VMs 2.8, 24.11

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      • A
        almabes
        last edited by

        @johnpoz:

        this is a device

        a4:93:4c:fd:ce:41

        Yes I show a4:93:4c as cisco..  so you need it track down that device sending the pings to this 1.2.3.4 so you can figure out why its sending them

        where exactly did you do the sniff?  Is there another router between the sender and pfsense?

        It's the VMWare device that's sending the ICMP Packets out.  You may have a compromised VM.

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        • johnpozJ
          johnpoz LAYER 8 Global Moderator
          last edited by

          where do you see vm sending anything?

          09:57:55.704554 a4:93:4c:fd:ce:41 > 00:50:56:88:78:f9

          that is sending to a vm, but the sending mac is cisco

          An intelligent man is sometimes forced to be drunk to spend time with his fools
          If you get confused: Listen to the Music Play
          Please don't Chat/PM me for help, unless mod related
          SG-4860 24.11 | Lab VMs 2.8, 24.11

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          • A
            almabes
            last edited by

            I must have read the packet trace wrong.  Oops.

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            • johnpozJ
              johnpoz LAYER 8 Global Moderator
              last edited by

              Dok - the OP stated their network is

              "no our Lan is 192.1.1.0/24"

              so I don't believe they are trying to actually use 100.64 space.. Or configured anything with an IP of 1.2.3.4

              Seems odd seeing multiple source IPs from the same mac, so I would guess a router or AP downstream of where pfsense is seeing the traffic.

              OP you need to track down what specific device that a4:93:4c:fd:ce:41 is, is traffic coming from something behind it?  What is this device exactly?

              An intelligent man is sometimes forced to be drunk to spend time with his fools
              If you get confused: Listen to the Music Play
              Please don't Chat/PM me for help, unless mod related
              SG-4860 24.11 | Lab VMs 2.8, 24.11

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              • A
                almabes
                last edited by

                Does pfSense have anything in its ARP cache for any of those CGN IPs? 
                Have you tried loading a box with nmap, putting it's interface IP in the CGN range and doing a scan?

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                • N
                  networking
                  last edited by

                  ok thanks for the help I have identified the cause. Gradually, the patch cord was removed and re- inserted until the duration inquiries have disappeared on the Main Switch. The result was that this is a Cisco device is our provider which is responsible for a private MPLS VPN tunnel. I now have the Provider sent the logs and note there to clarify that this is stopped.

                  Is it worth the private network in an RFC compliant convert? So we all Devices by
                  192.1.1.x / 24
                  in
                  192.168.1.x / 24
                  bring ?

                  Does it then 192.1.2.x create sense due to broadcast and Performance for the server space? And if so, how and where this route I then in the PFSense. Is there a FAQ about?

                  I know VLANs are there also but the first are not a solution .

                  Many thanks for your help!  :)

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                  • johnpozJ
                    johnpoz LAYER 8 Global Moderator
                    last edited by

                    192.1 is not rfc19181 address space..

                    Why would they have been pinging 1.2.3.4?

                    An intelligent man is sometimes forced to be drunk to spend time with his fools
                    If you get confused: Listen to the Music Play
                    Please don't Chat/PM me for help, unless mod related
                    SG-4860 24.11 | Lab VMs 2.8, 24.11

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                    • H
                      Harvy66
                      last edited by

                      @johnpoz:

                      192.1 is not rfc19181 address space..

                      Why would they have been pinging 1.2.3.4?

                      A lot of programmers wrote code that would attempt to ping the 1.0.0.0 /8 because the "knew it was not in use". Not any more. I forget the reasoning behind this. I think some of it is they wanted to use a public IP range internally and they figured it was safe, but now all /8s are in use. I remember reading a lot of these stories shortly after the 1.x block got handed out and some of the IPs like 1.1.1.1 were suddenly getting flooded with traffic from around thew world because of idiot programmers doing this sort of crap.

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                      • C
                        cmb
                        last edited by

                        @almabes:

                        Does pfSense have anything in its ARP cache for any of those CGN IPs?

                        It wouldn't, they're sourced from the Cisco layer 3 switch's MAC address, so it's routing it from somewhere behind it. Checking the Cisco is the next place to track it down.

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