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    I have no idea whos causing this traffic....

    Scheduled Pinned Locked Moved General pfSense Questions
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    • johnpozJ
      johnpoz LAYER 8 Global Moderator
      last edited by johnpoz

      Also if you go to just the traffic graph section.. You might catch the burst being listed, and what local IP is involved.. But sniff be easier to be honest.

      Other options looking via the iftop package or the darkstat package to see who is generating traffic.

      And concur such bursting does seem like some sort of streaming going on - I see such patterns when clients streaming from my plex..

      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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      • GertjanG
        Gertjan
        last edited by

        Graph section ? Packet sniffing ? These options are in the GUI, right in front of our nose.
        Because Cool_corona asked the question, he wasn't using these for reasons.

        Two more solutions : one with the GUI involved, and one that needs a pair of baskets ....
        First approach :
        Place 2 firewall rules on my LAN.
        The first contains an alias, used as a Source, Destination and protocol is set to any. Init the alias with all the IP's used on the LAN network.
        The second rule is any to any block rule a block rule.

        Check that the spikes are there.
        Now, remove an LAN IP from the alias.
        Check again - if the spikes are gone, you found the IP. If not, remove another IP from the alias.

        With the IP, locate the device. Locate the owner of the device. Have a chat.

        Second approach :
        Even more easier : disconnect physically all LAN devices, and while the spikes are not there, hook them back up one by one. Tip : locate a switch, all the cables are there.
        As soon as the spikes come back, you have the device by it's "tail".

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

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        • johnpozJ
          johnpoz LAYER 8 Global Moderator
          last edited by johnpoz

          @Gertjan said in I have no idea whos causing this traffic....:

          Second approach :
          Even more easier : disconnect physically all LAN devices,

          While that can work sure - I wouldn't call it easier ;) Seems like a lot of work to me - compared to just simple sniff.. hehehe Unless your goal is to get up out of your chair.. Which could be good thing ;)

          All valid methods of how to skin this specific cat ;)

          Other methods, firewall rule is option I didn't think of actually.. would show you where the traffic is going as well which could be insightful in figuring out what exactly the traffic is.

          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

          JKnottJ 1 Reply Last reply Reply Quote 0
          • JKnottJ
            JKnott @johnpoz
            last edited by

            @johnpoz said in I have no idea whos causing this traffic....:

            All valid methods of how to skin this specific cat ;)

            CAT 6? 😉

            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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            • AKEGECA
              AKEGEC
              last edited by

              @Cool_Corona , Decoy network?

              Cool_CoronaC 1 Reply Last reply Reply Quote 0
              • Cool_CoronaC
                Cool_Corona @AKEGEC
                last edited by

                @AKEGEC said in I have no idea whos causing this traffic....:

                @Cool_Corona , Decoy network?

                Nope :)

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                • DaddyGoD
                  DaddyGo @Cool_Corona
                  last edited by

                  @Cool_Corona said in I have no idea whos causing this traffic....:

                  Any ideas?

                  L3 switch + mirror port and / or SPAN protocol is your good friend, if you want to get a detailed picture

                  Cats bury it so they can't see it!
                  (You know what I mean if you have a cat)

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                  • johnpozJ
                    johnpoz LAYER 8 Global Moderator
                    last edited by

                    While sure he could view the traffic via a span port.. There really is no need, just diagnostic menu packet capture will allow him to do a sniff and see the traffic flow through pfsense to figure out what IP is involved and where it going.

                    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

                    DaddyGoD 1 Reply Last reply Reply Quote 0
                    • DaddyGoD
                      DaddyGo @johnpoz
                      last edited by DaddyGo

                      @johnpoz said in I have no idea whos causing this traffic....:

                      just diagnostic menu packet capture

                      Sorry, I was thinking about Wireshark (it was missed), plus what was described above.
                      Personally, I like it better as packet capture in pfsense tool

                      +++edit:
                      much more configurable and detailed

                      Cats bury it so they can't see it!
                      (You know what I mean if you have a cat)

                      JKnottJ 1 Reply Last reply Reply Quote 0
                      • johnpozJ
                        johnpoz LAYER 8 Global Moderator
                        last edited by johnpoz

                        You understand you can just download whatever the packet capture captures into wireshark right? Just click the download button ;) And then open it up with wireshark or whatever your fav tool is..

                        A pcap is a pcap ;) While true the gui interface doesn't really show you a lot of detail on the capture. but if all he is really interested is the IP causing the traffic and what port its talking to - the gui would provide that info for sure. You can also always up the level displayed - but yeah I pretty much always download the pcap into wireshark when want to analyze some sniff.

                        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

                        DaddyGoD 1 Reply Last reply Reply Quote 0
                        • DaddyGoD
                          DaddyGo @johnpoz
                          last edited by

                          @johnpoz said in I have no idea whos causing this traffic....:

                          You understand you can just download whatever the packet capture captures into wireshark right?

                          I agree with you, I may just be used to clicking the Wireshark icon and the SPAN VLAN is connected anyway.
                          I handle multiple things on multiple networks and it’s that simple..

                          if don't need deep investigation the pfSense GUI is enough

                          Cats bury it so they can't see it!
                          (You know what I mean if you have a cat)

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                          • JKnottJ
                            JKnott @DaddyGo
                            last edited by

                            @DaddyGo said in I have no idea whos causing this traffic....:

                            Sorry, I was thinking about Wireshark (it was missed), plus what was described above.
                            Personally, I like it better as packet capture in pfsense tool

                            I mentioned Packet Capture. I also prefer Wireshark, but it won't run on pfsense, so either you run it on a computer that can see the traffic or use Packet Capture and download to Wireshark. If you have a managed switch, you can set up port mirroring to watch the desired connection, at least on the LAN side.

                            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...

                            DaddyGoD 1 Reply Last reply Reply Quote 0
                            • PippinP
                              Pippin
                              last edited by

                              It's also possible to do remote capture.
                              Wireshark connects to pfSense over SSH in that case.

                              I gloomily came to the ironic conclusion that if you take a highly intelligent person and give them the best possible, elite education, then you will most likely wind up with an academic who is completely impervious to reality.
                              Halton Arp

                              JKnottJ 1 Reply Last reply Reply Quote 0
                              • JKnottJ
                                JKnott @Pippin
                                last edited by

                                @Pippin

                                I used to do that, when I had a Linux firewall. However, it's not possible to run it on pfsense, IIRC.

                                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...

                                bingo600B 1 Reply Last reply Reply Quote 0
                                • DaddyGoD
                                  DaddyGo @JKnott
                                  last edited by DaddyGo

                                  @JKnott said in I have no idea whos causing this traffic....:

                                  I also prefer Wireshark, but it won't run on pfsense, so either you run it on a computer that can see the traffic or use Packet Capture

                                  I agree with you too 😉

                                  so I wrote the L3 switch (above) + mirror port
                                  (even on a smaller network, it’s worth just keeping one in your desktop drawer for testing)

                                  we use SPAN VLAN on the Cisco network and we are testing here with Wireshark
                                  (I got used to it and simple method)

                                  I don't like TP-Link, but for a mobile test device it fits a lot (we use it :-)) TL-SG105E, it knows the port mirroring and thats all

                                  Cats bury it so they can't see it!
                                  (You know what I mean if you have a cat)

                                  JKnottJ 1 Reply Last reply Reply Quote 0
                                  • johnpozJ
                                    johnpoz LAYER 8 Global Moderator
                                    last edited by johnpoz

                                    My bet is someone streaming off plex ;) or something similar - there is another thread about graphs showing double - and the @Cool_Corona posted image looks exactly like how plex can stream data to a client..

                                    Here is mine that I just used for image in that other thread.

                                    plexpng.png

                                    While someone streaming off my plex, lower data rates is all - he prob has higher bitrate movies on his ;)

                                    Here is plex showing the data
                                    plexdash.png

                                    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

                                    1 Reply Last reply Reply Quote 0
                                    • JKnottJ
                                      JKnott @DaddyGo
                                      last edited by

                                      @DaddyGo said in I have no idea whos causing this traffic....:

                                      (even on a smaller network, it’s worth just keeping one in your desktop drawer for testing)

                                      See my post Creating a "data tap". I also use a TP-Link TL-SG105E switch. I carry it in my computer bag and have also used it as a plain switch on occasion. Since I use a port based VLAN on it, instead of tags, it works fine.

                                      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...

                                      DaddyGoD 1 Reply Last reply Reply Quote 0
                                      • DaddyGoD
                                        DaddyGo @JKnott
                                        last edited by

                                        @JKnott said in I have no idea whos causing this traffic....:

                                        I also use a TP-Link TL-SG105E switch

                                        Well, then we think on the same way 😉

                                        Cats bury it so they can't see it!
                                        (You know what I mean if you have a cat)

                                        1 Reply Last reply Reply Quote 0
                                        • M
                                          marvosa
                                          last edited by marvosa

                                          One crude option is watching the traffic graph live (Status -> Traffic Graph) and changing the interface to LAN. Depending on your network design, if you're not seeing any data, you may also have to change the filer to "Remote".

                                          Another option is to install the ntopng package. In the ntopng settings menu, make sure that all of your LAN interfaces are tagged. Once in the ntopng webgui, click on the "Flows" menu across the top and you will see details (protocol, source, destination, throughput, etc) about each connection. From there I would sort by the "Actual Thpt" column so the connections generating the most bandwidth are at the top of the list.

                                          Yet another option is installing the softflowd package and pointing it at a netflow collector like PRTG.

                                          I would use ntopng. You should be able to find the offending device in a few min.

                                          1 Reply Last reply Reply Quote 1
                                          • AKEGECA
                                            AKEGEC
                                            last edited by

                                            I think I saw similar forum thread from Belgian op not long ago. I am not sure if he already found the solution.

                                            Wireshark is a great tool but if I may suggest, use QRadar CE (FREE) to analyze your live Pfsense logs.

                                            alt text

                                            alt text

                                            Like today, I found a lot offensive IP addresses.

                                            DaddyGoD 1 Reply Last reply Reply Quote 0
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