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    Bug or hacking by udp flooding ?

    Scheduled Pinned Locked Moved General pfSense Questions
    17 Posts 6 Posters 2.0k Views
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    • T
      Thilroy
      last edited by

      Johnpoz, thanks for your answer, it makes sense.

      Although…

      • Is a BOOTP request something normal for an android device connecting to a wifi network ? I don't think so.
      • as I've told before, I've checked the port counters on the switches, and it appears that all the traffic seems to originate from the firewall. When I tried to follow the traffic's flow, I saw :
            - on the FW switch : incoming frames from the fw and outgoing frames to the next switch
            - on the GW switch : incoming frames from the FW switch and outgoing frames to the gateway ports.

      - BUT, and that's the important point, no incoming frames from the switch to the internal FW interface !

      So, where does this traffic comes from, if not from the fw itself ? And I insist again on the fact that either deleting the state in the FW or restarting it just kills the problem.

      Sorry for being nerdy…

      Thanks,

      Thierry

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      • GruensFroeschliG
        GruensFroeschli
        last edited by

        Since you say you are using VLANs.
        Do you by chance have a place where you have tagged and untagged traffic on the same wire?

        Are you using static routes from your pfSense pointing to the gateway going to the 192.168 net?

        We do what we must, because we can.

        Asking questions the smart way: http://www.catb.org/esr/faqs/smart-questions.html

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        • T
          Thilroy
          last edited by

          Hi GreenFrog,

          Yes, this is possible.
          As for the routes, the firewall is doing the routing between the different VLANs, and has several intefaces configured, about one per VLAN plus a few extras. There is an interface for the 192.168.1 network, and a VLAN as well.

          Thank you

          Thierry

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          • H
            heper
            last edited by

            I'd enable broadcast storm protection on your access ports & ap links.

            Also, block that mac-address on your WiFi controller.

            There must be a configuration issue somewhere because 30kps won't be from any WiFi devices.

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            • T
              Thilroy
              last edited by

              Broadcast control, I've done it already. I just didn't block the MAC address yet because I wanted to find a way to identify the owner…. but don't see how.

              Thks,

              Thierry

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              • johnpozJ
                johnpoz LAYER 8 Global Moderator
                last edited by

                When they can't get on your network - pretty sure they will contact you ;)

                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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                • GruensFroeschliG
                  GruensFroeschli
                  last edited by

                  I asked about the mixing of tagged and untagged traffic because i once had a misconfiguration where a device which wasn't vlan aware started leaking frames between the tagged vlans and the untagged subnet.
                  This lead to frames circulating between the tagged and untagged parts.
                  –> Essentially a logical loop even if no physical loop was present.

                  If you can capture with a tap (or a hub..) the wire which could carry tagged/untagged mixed you should see it because you see the same frame over and over tagged and untagged.

                  How i solved my problem:
                  Got rid of the untagged traffic on this segment.
                  Some disagree, but i still am of the opinion that the rule-of-thumb of "don't mix tagged and untagged traffic on the same cable" applies.

                  We do what we must, because we can.

                  Asking questions the smart way: http://www.catb.org/esr/faqs/smart-questions.html

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                  • jimpJ
                    jimp Rebel Alliance Developer Netgate
                    last edited by

                    You might be hitting something like this: https://redmine.pfsense.org/issues/2073

                    Basically, you might have a policy routing rule (rule with a gateway set) that matches too much traffic. If the firewall tries to policy route broadcast traffic, bad things like this can happen. Now it's usually smart enough to not do that for addresses in a subnet it knows directly, but if you have a rule to policy route traffic with a source of "any" and it matches some other subnet's broadcast packet, it doesn't know the difference.

                    Fix the rule, clear the states or reboot, and you might be OK again. Assuming that's the problem, but the symptoms fit.

                    Remember: Upvote with the 👍 button for any user/post you find to be helpful, informative, or deserving of recognition!

                    Need help fast? Netgate Global Support!

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                    • johnpozJ
                      johnpoz LAYER 8 Global Moderator
                      last edited by

                      "but i still am of the opinion that the rule-of-thumb of "don't mix tagged and untagged traffic on the same cable" applies."

                      I would be one that disagrees ;)  And with some devices its not even possible.. Case in point would be management of say an AP that does not allow you to tag its management vlan.  But there is only 1 wire to connect the AP.  So the wifi/ssids are tagged vlans while traffic to manage the AP is not tagged.  Ie a native or PVID of the interface on the switch.

                      This should never be a problem if your switching environment is correctly configured to keep this untagged management vlan isolated to only the ports that it needs to be on.

                      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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                      • T
                        Thilroy
                        last edited by

                        Thanks for your help. I will investigate further on those grounds.
                        I'll keep you filed.

                        Thierry

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