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    pfSense stops routing IPv6 after a few days

    Scheduled Pinned Locked Moved IPv6
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    • ?
      A Former User
      last edited by A Former User

      This post is deleted!
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      • M
        msmith100 @JKnott
        last edited by

        @jknott Oops I think I should have been more clear. I mean a /64 for the WAN, and a /56 delegated to 1+ LAN networks, each of which is assigned 1 of 256 /64's from that /56 by pfsense per your configuration.
        My current config, masked for privacy:

         WAN (wan)       -> pppoe0     -> v4/PPPoE: 104.163.xxx.xxx/32
                                          v6/DHCP6: 2606:6d00:1234:1234:1234:1234:1234:1234/64
         LAN (lan)       -> bge0       -> v4: 192.168.0.100/24
                                          v6: 2606:6d00:8888:1111::1/64
        .....
         VLAN4(opt4)   -> bge0.3     -> v4: 192.168.11.100/24
                                          v6: 2606:6d00:8888:1112::1/64
        

        As I understand it, I could even not have a globally routable address on the WAN, and it would have no effect. I've seen some other people setup pfsense in that manner, actually - I think on Teksavvy?

        @ijeff As long as your config matches what the ISP provides, then there should be no issue and it's their problem. I have heard of cases on various forums though of some ISPs with really strange configs (e.g. Telus on the west coast), including requiring non-standard (i.e. modifying config files manually) behavior w.r.t. DHCP renewing and such. That might be the case in your situation - pfsense is following standard RFCs, and your ISP is not. Further complicating manners, there are also some ISP-grade routers out there with known issues that had to be patched to fix weird IPv6 behavior in the last few years.

        Wish I could help further...

        JKnottJ 1 Reply Last reply Reply Quote 0
        • I
          ijeff
          last edited by ijeff

          So would it in theory be possible to use fe80:: addresses on the LAN side and have the router use NAT to pass everything through the single IPv6 address?

          JKnottJ 1 Reply Last reply Reply Quote 0
          • JKnottJ
            JKnott @msmith100
            last edited by

            @msmith100 said in pfSense stops routing IPv6 after a few days:

            As I understand it, I could even not have a globally routable address on the WAN, and it would have no effect. I've seen some other people setup pfsense in that manner, actually - I think on Teksavvy?

            Quite possibly your WAN address is not used for routing. Check your default route with the netstat -r command. Don't be surprised if you see a link local address.

            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...

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

              @ijeff

              Why on earth would you want to do that? NAT was created to get around the IPv4 address shortage. On IPv6, a single /64 contains 18.4 billion, billion addresses.

              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...

              I 1 Reply Last reply Reply Quote 0
              • I
                ijeff @JKnott
                last edited by

                @jknott

                Seemed like a quick and dirty way of getting IPv6 if my ISP has a non-compliant setup? If it’s not the way to do it then that’s fine.

                Someone elsewhere has mentioned that I should investigate enabling large ICMP and ICMP v6 since that’s not allowed on the WAN side of the firewall, but I’m not on site at the moment.

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

                  @ijeff

                  What do you mean by "large ICMP"? That would tend to indicate an attack.

                  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...

                  I 1 Reply Last reply Reply Quote 0
                  • I
                    ijeff @JKnott
                    last edited by

                    @jknott

                    They specifically mentioned to make sure the following was enabled:

                    • Allowing large ICMP
                    • Allowing v6 ICMP across the network
                    M 1 Reply Last reply Reply Quote 0
                    • M
                      msmith100 @JKnott
                      last edited by

                      @jknott No it's not. Still useful to have for pfsense itself as a pseudo-privacy layer e.g. for DNS requests, and I assume there is at least some good if non-essential reason it's part of an RFC and done by default by my ISP.

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                      • M
                        msmith100 @ijeff
                        last edited by

                        @ijeff I have no idea how that would help you. AFAIK by default pfsense has rules that allow the bare minimum essential IPv6 ICMP traffic, so that shouldn't be the cause of your issue.

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                        • I
                          ijeff @msmith100
                          last edited by

                          @msmith100

                          I think you're right, it looks like pfSense is doing everything it needs to by default.

                          I've been referred to this bug which seems to explain the exact issue I'm having. My ISP and the ISP mentioned in the bug actually use very similar network hardware (Cisco Nexus) so it may be completely related to that...

                          I might wait until 2.5.0 is released with this bug fixed before trying further troubleshooting...

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                          • I
                            ijeff
                            last edited by

                            I've upgraded to 2.5.0 today and will monitor and report back.

                            1 Reply Last reply Reply Quote 0
                            • I
                              ijeff
                              last edited by

                              No further issues since upgrading to 2.5.0. Looks like the bugs have been squashed!

                              1 Reply Last reply Reply Quote 0
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