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    VLAN members get assigned multiple IPv6 addresses

    Scheduled Pinned Locked Moved IPv6
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    • JKnottJ
      JKnott @Sector8899
      last edited by

      @W5Ofwur1xtOmtk9ZBO

      Any chance you have a TP-Link managed switch? Some models have a problem where multicast packets leak between VLANs, which means devices will get addresses from the other VLANs. I have the same problem with my TP-Link access point.

      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...

      S 1 Reply Last reply Reply Quote 1
      • S
        Sector8899 @JKnott
        last edited by

        @JKnott
        yes, exactly.

        Is there anything I can do about this? It's the only switch that I have. Just bought it for this purpose. Unfortunately it was about a month ago now. So I can't return it

        JKnottJ 1 Reply Last reply Reply Quote 0
        • JKnottJ
          JKnott @Sector8899
          last edited by

          @W5Ofwur1xtOmtk9ZBO said in VLAN members get assigned multiple IPv6 addresses:

          Is there anything I can do about this?

          About the only thing you can do is update the firmware, provided an update is available. Otherwise, you could turn the switch into a data tap, for monitoring networks with Wireshark. Those switches work reasonably well in that role.

          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...

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

            What is the exact model number and hardware version v1,2 v4, etc. if the tplink switch me and jknott had discussed quite a bit here if your v2 or below your out of luck... But v3 did have some firmware that was suppose to fix the issue.

            Good luck - if no put it on your shelf and get a better make.. the netgear and dlink both do what they say and same price points.

            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

            S 1 Reply Last reply Reply Quote 0
            • S
              Sector8899 @johnpoz
              last edited by

              @johnpoz I have the V4, but I'm already on the newest firmware (2018-11-30)

              JKnottJ 1 Reply Last reply Reply Quote 0
              • JKnottJ
                JKnott @Sector8899
                last edited by

                @W5Ofwur1xtOmtk9ZBO said in VLAN members get assigned multiple IPv6 addresses:

                @johnpoz I have the V4, but I'm already on the newest firmware (2018-11-30)

                Then I guess you'll have to get another make. As I mentioned, you have the makings of a data tap, which can come in handy if you're really into networking. Which model switch did you get?

                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...

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

                  So its still broken even in V4... Wow what CRAP!!

                  Go with netgear or dlink then - they both work as they should for vlan isolation.

                  You sure its problem in the device, vs your config - you removed say vlan 1 from all your ports that you want in other vlans.. That is the problem with the older models and firmwares - you could not remove vlan 1 from ports that you wanted in other vlans. So pretty much you just had dumb switch where all ports are in vlan 1. And you could think you were doing tagging of vlan X, etc.

                  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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                  • S
                    Sector8899
                    last edited by

                    Are you guys sure that it's the switch's fault? I'm still somewhat suspicious about the whole thing.

                    I'm using a wifi-router as an AP on the VLAN. I don't understand how the IPv6 is leaking through that AP to my phone on that network.

                    Then, I disabled IPv6 for the entire VLAN (in pfsense). But I still get an IPv6 and IPv6 DNS on the VLAN-device.

                    Then, I disabled the IPv6 on the wifi router (AP), but I'm STILL getting an IPv6. I don't understand how the switch can force these IPs through all the way to my phone.

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

                      No not sure.. You do understand that IPv6 can be auto configured by the device right, and it could be just link-local address.

                      Your really going to need to show us how you have everything connected, diagram and what IPs your getting that you think you shouldn't be getting.

                      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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                      • JKnottJ
                        JKnott @Sector8899
                        last edited by

                        @W5Ofwur1xtOmtk9ZBO said in VLAN members get assigned multiple IPv6 addresses:

                        Are you guys sure that it's the switch's fault? I'm still somewhat suspicious about the whole thing.

                        This is where Wireshark really comes in handy. You can look at the packets to see the VLAN tags, IP addresses, etc. Wireshark is an excellent tool for resolving network issues. PfSense has a built in Packet Capture, but it's limited compared to Wireshark. One thing you might try, assuming you have VLANs configured on pfSense and a port on the switch configured for VLAN 10. If a computer, running Wireshark, is connected to that port, Wireshark should show only traffic intended for VLAN 10. If you see stuff, such as router advertisements from other that VLAN 10, then you have that TP-Link problem. To do this filter on ICMP6.

                        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...

                        1 Reply Last reply Reply Quote 0
                        • NogBadTheBadN
                          NogBadTheBad
                          last edited by

                          Packet capture on the parent interface, download into wireshark and set up a column for the vlan id like I mentioned in this post:-

                          https://forum.netgate.com/topic/145609/vlan-interface-on-wan-interface-not-tagging-frames/5

                          Andy

                          1 x Netgate SG-4860 - 3 x Linksys LGS308P - 1 x Aruba InstantOn AP22

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                          • DerelictD
                            Derelict LAYER 8 Netgate
                            last edited by

                            Are the addresses being assigned out of the same /64 or /64s from different VLANs?

                            Perfectly normal and expected for there to be multiple if not several IPv6 addresses on an interface, but they should all be inside the interface prefix.

                            We know pfSense is tagging the traffic properly. The problem is that switch doesn't properly isolate broadcast (multicast) domains or is misconfigured.

                            I would never use one of those switches in any network that mattered to me. I would use it for test stuff (like a tap, as mentioned) or throw it away.

                            Chattanooga, Tennessee, USA
                            A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                            DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                            Do Not Chat For Help! NO_WAN_EGRESS(TM)

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