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    Broadcast packets duplicated across VLAN

    Scheduled Pinned Locked Moved L2/Switching/VLANs
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    • johnpozJ
      johnpoz LAYER 8 Global Moderator @JKnott
      last edited by

      @jknott clearly - they should not be on the same ;) that is for sure - they would just fight ;)

      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 2.7.2, 24.11

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      • N
        nazuro
        last edited by nazuro

        @jknott @johnpoz

        Apologies for any confusion. John is correct that VPN is just what I'm calling my VLAN. It enables me to connect physical / wireless devices to it and that traffic then exits via OpenVPN to the internet via an AirVPN endpoint.

        My 11.103 address is MacBook Pro wireless. 13.147 is my iPad. I did just have a particularly bad bout of wireless problems and observed this in the logs. I don't believe my MacBook is switching SSIDs and did previously confirm this by forgetting all SSIDs apart from the Main.

        Screenshot 2021-07-06 at 21.30.27.png
        I have followed this guide pretty closely https://nguvu.org/pfsense/pfsense-baseline-setup/. Perhaps I am out of my depth - I am working through CISSP at the moment but still much different in practice than in theory. I found it easier conceptually to leave the parent interface (LAN) as just that, and have four different VLANs that I would use operationally and could easily apply firewall rules to each of the virtual interfaces without interfering with the parent interface.

        Things do seem quite a bit worse now since I tweaked the Unifi settings and minor changes on the switch. I'm going to try put everything back to how it was, and do more analysis specifically on what I'm seeing with these firewall logs and get another pcap. Appreciate both of your help very much so.

        edit: Perhaps if there's some way of me locally tagging traffic from my MacBook on VLAN 11 I could plug directly in to the LAN on pfSense and rule out an issue with the switch.

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          nazuro @nazuro
          last edited by

          I've just taken a short pcap on LAN port on pfSense. 192.168.11.103 is still my MacBook and I renewed the DHCP lease twice during the pcap pcap7.pcap

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          • johnpozJ
            johnpoz LAYER 8 Global Moderator @nazuro
            last edited by johnpoz

            And here you go.. Here is arp announcement from your apple - tagged with both 11 and 13

            arp.png

            Here is your dhcp also 1 tagged 11, other 13

            dhcp.png

            So yes pfsense would see this on both of its vlan interfaces, because the traffic tagged. So either your apple is tagging this traffic, or your wifi is doing it.. But that explains why pfsense is seeing the traffic on both interfaces - because its tagged for both vlans

            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 2.7.2, 24.11

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            • N
              nazuro @johnpoz
              last edited by

              @johnpoz Understood. Problem is it's not just my Apple but also other devices (wired and wireless) including windows too. Must be something happening on the Netgear switch then I suppose, although it's a fairly standard 802.1Q setup I have got going on.

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              • johnpozJ
                johnpoz LAYER 8 Global Moderator @nazuro
                last edited by johnpoz

                What wired device in that sniff? So I can look for those.

                Nothing else jumped out at me..

                This is ODD.. you have this unifi mac asking for who is 11.1 with 11 and 13 tagged

                odd.png

                what is 11.9?

                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 2.7.2, 24.11

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                • N
                  nazuro @johnpoz
                  last edited by nazuro

                  @johnpoz 192.168.11.117 in this pcap is wired in to the switch on an Untagged VLAN 11 port (wireless on this laptop is turned off) pcap8.pcap

                  edit: 11.9 is the IP address of the Unifi AP

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                  • johnpozJ
                    johnpoz LAYER 8 Global Moderator @nazuro
                    last edited by johnpoz

                    who is this

                    whoisthis.png

                    asking for 13.100, from 13.1 in both 11 and 13..

                    Something for sure is all messed up..

                    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 2.7.2, 24.11

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                    • N
                      nazuro @johnpoz
                      last edited by

                      @johnpoz 00:1b:21:33:9e:e9 is the MAC address of the LAN NIC (igb1) in pfSense. Therefore igb1.1, igb1.2, igb1.3, igb1.4 also share the same MAC address

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                      • N
                        nazuro @nazuro
                        last edited by nazuro

                        This post is deleted!
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                        • N
                          nazuro
                          last edited by nazuro

                          @johnpoz said in Broadcast packets duplicated across VLAN:

                          asking for 13.100, from 13.1 in both 11 and 13..
                          Something for sure is all messed up..

                          In case you are interested, I contacted Netgear support and they say it's an issue with my switch:

                          "As I have this inquired to my senior experts, seems like the behavior of GS116ev2 Plus Switch is causing the issue for the certain VLAN. Since GS116Ev2 does not have native VLAN nor management VLAN ID, any DHCP request is being sent to all ports. As advised and to have this be corrected, Smart Pro switches are recommended."

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