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    Broadcast packets duplicated across VLAN

    Scheduled Pinned Locked Moved L2/Switching/VLANs
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    • JKnottJ
      JKnott @nazuro
      last edited by

      @nazuro

      Further on this. Several years ago, I had one job that had 3 VLANs. It was a senior citizens residence, occupying 3 towers. In addition to the main native LAN for the office, there were VLANs for VoIP, network management and Internet to the resident's rooms. That is the only time I've had that many VLANs and I don't understand why you need 4.

      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...

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

        @jknott said in Broadcast packets duplicated across VLAN:

        why you need 4.

        You don't understand why someone might want to isolate wifi to more than 4 vlans? Come on!

        I have 4, and really could use more.. My main trusted vlan, my psk vlan, my roku vlan, and then a guest vlan.

        I could see busting out a few more.. I have a few different devices sharing my psk vlan.. I could see breaking those out to different vlans for different devices, etc. For example when I setup some camera's I would want those on their own camera vlan. And I should really break out all my lightbulbs to their own vs being on the same vlan as my other iot devices.. Just lazy and let them share the same vlan..

        edit: Thinking about this for a few minutes - my "guess" is this 103 device is wireless and its changing the ssid its connected to. Say for example when it cant get to that 13.147 address via the vpn ssid, it jumps to another ssid to try and get there. That would explain the 9 second span between firewall hits.

        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

          I can understand why there might be a need for more VLANs. What I don't understand is why he needs 4, based on what he's mentioned. For example, what's with the VPN on a VLAN? Where does the VLAN terminate? If other than on pfsense, that complicates routing. As discussed, the main LAN also shouldn't be on a VLAN. That leaves 2. Sure, I could put my TV on it's own VLAN, but the guest WiFi is good enough for that. Even then, the only reason the TV isn't on my main LAN is it chokes on the 63 character password I use on it. I suppose I could put my IPTV boxes on a separate VLAN, but haven't bothered.

          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...

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

            @jknott said in Broadcast packets duplicated across VLAN:

            what's with the VPN on a VLAN?

            My take and have seen many users do this.. They create a vlan, that all devices on this vlan are routed out a vpn connection. So for example if he wants to use the vpn on his phone for "something" he just changes the ssid he is connected to. Maybe netflix doesn't work via the vpn, so when he wants to watch netflix on is phone he changes to different ssid that is not routed out the vpn.

            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 1
            • JKnottJ
              JKnott @johnpoz
              last edited by

              @johnpoz

              I suppose I could give my dog & cat their own VLANs. 😉

              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...

              johnpozJ 1 Reply Last reply Reply Quote 0
              • 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 2.8, 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.

                  N 1 Reply Last reply Reply Quote 0
                  • N
                    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 2.8, 24.11

                      N 1 Reply Last reply Reply Quote 0
                      • 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.

                        johnpozJ 1 Reply Last reply Reply Quote 0
                        • 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 2.8, 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

                            johnpozJ 1 Reply Last reply Reply Quote 0
                            • 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 2.8, 24.11

                              N 1 Reply Last reply Reply Quote 0
                              • 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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