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    IPv6 cannot connect to Internet

    Scheduled Pinned Locked Moved IPv6
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    • crazypotato142C Offline
      crazypotato142 @Gertjan
      last edited by

      @Gertjan
      It's very interesting it started to do so out of nowhere.

      I have these 2 rules as well, you can see on the first post.

      On logs it says it is being blocked by a default deny rule but i have no clue what and where it is.

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      • Bob.DigB Offline
        Bob.Dig LAYER 8 @crazypotato142
        last edited by Bob.Dig

        @crazypotato142 said in All IPv6 traffic is being blocked:

        And yes, also my device gets an IP with that prefix:

        Show them completely or do you have static IPv6. That Windows is showing three preferred "IPv6-Addresses" alone shows that here is a problem. Often though the problem is with pfSense itself and you might not be able to fix it. There were already two prefix-changes from your ISP but your Windows doesn't know about those and that is most probably on pfSense.
        If the problem is persistent for you, you could deploy ULA on your LAN and then do NPt (tracked from an unused VLAN). That has the benefit that for Windows, the prefix never changes because it only knows about the ULA.

        Screenshot 2025-09-29 172125.png

        In my example, the ULA-prefix is from my LAN and the tracked prefix is from a VLAN named "TRACK1WAN1".

        crazypotato142C 1 Reply Last reply Reply Quote 0
        • crazypotato142C Offline
          crazypotato142 @Bob.Dig
          last edited by

          @Bob.Dig
          No, my IPv6 is not static. They came out when I restarted my WAN multiple times while tryna fix it today. And one seems "Deprecated" right now.

          Will NPt really fix it? Because I clearly can see that pfSense blocks whatever I do on my Firewall Logs.

          Bob.DigB 1 Reply Last reply Reply Quote 0
          • Bob.DigB Offline
            Bob.Dig LAYER 8 @crazypotato142
            last edited by Bob.Dig

            @crazypotato142 said in All IPv6 traffic is being blocked:

            Because I clearly can see that pfSense blocks whatever

            It blocks is probably because it knows that those prefixes are not valid anymore but your Windows doesn't know and still uses those. So the answer is yes.
            My prefix is changing daily so I know a thing about this. 😉

            JKnottJ 1 Reply Last reply Reply Quote 0
            • JKnottJ Offline
              JKnott @Bob.Dig
              last edited by

              @Bob.Dig said in All IPv6 traffic is being blocked:

              It blocks is probably because it knows that those prefixes are not valid anymore but your Windows doesn't know and still uses those. So the answer is yes.
              My prefix is changing daily so I know a thing about this.

              I had thought about that too. He could capture the DHCP6 sequence to see if the assigned prefix is what the Windows computers are using.

              PfSense running on Qotom mini PC
              i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel 1 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 0
              • S Offline
                SteveITS Rebel Alliance @JKnott
                last edited by

                "ipconfig /all" will show a list:

                Ethernet adapter Connection Name:
                (...)
                IPv6 Address. . . . . . . . . . . : 2603:300a:***:34b(Preferred)
                  Temporary IPv6 Address. . . . . . : 2603:300a:***:8b18(Preferred)
                

                I've seen my PC have 10-15 or so, and yes if it changes the old ones have to die off or be removed so Windows will start using the newer ones.

                netsh interface ipv6 delete address interface="Connection Name" IPV6HERE
                

                We have a semi-related issue where the prefix changes when Comcast updates our modem but ISC DHCP apparently won't honor "deny unknown clients" for IPv6 and I haven't had a chance to try Kea again after hours. So I've been updating our routers manually, and (my point is) we use a relatively short lease time. But I digress...

                Only install packages for your version, or risk breaking it. Select your branch in System/Update/Update Settings.
                When upgrading, allow 10-15 minutes to reboot, or more depending on packages, and device or disk speed.
                Upvote 👍 helpful posts!

                crazypotato142C 1 Reply Last reply Reply Quote 0
                • crazypotato142C Offline
                  crazypotato142 @SteveITS
                  last edited by

                  When I checked again all IPv6 addressed were deprecated. I restarted the NIC and now it has a single IP matches with the prefix on pfSense. There is no blocking on logs but it still doesn't connect anywhere over IPv6.

                  I'm just asking to understand the process: Shouldn't it work this way if it's the thing you guys told about? @Bob.Dig @JKnott

                  Bob.DigB JKnottJ 2 Replies Last reply Reply Quote 0
                  • GertjanG Offline
                    Gertjan @crazypotato142
                    last edited by Gertjan

                    @crazypotato142

                    If you use / stick with DHCPv6 (server) you can use this :

                    af98d4c3-da23-4ca4-b3bc-4e292ccda79d-image.png

                    to make a 'static DHCPv6 lease" :

                    760a7d8f-726c-4059-acce-8ada4965ee11-image.png

                    and from then on, that PC will only get the (one) ::cc IPv6, with the current prefix prepended.

                    Btw : my ISP IPV6 prefix, used for my LAN, rarely change.

                    @crazypotato142 said in All IPv6 traffic is being blocked:

                    again all IPv6 addressed were deprecated. I restarted the NIC

                    Not needed.
                    Type :

                    ipconfig /renew6
                    

                    @crazypotato142 said in All IPv6 traffic is being blocked:

                    Shouldn't it work this way if it's the thing you guys told about?

                    Sure. Just keep in mind : On paper, IPv6 is ready, well defined, and should work well.
                    The thing is, there are probably a couple of ISPs (the ISP, the upstream router etc) out there that do respect fully the IPv6 guide lines (RFCs). The other 99,9 % make a mess out of it - doing their own 'things'.
                    Even pfSense isn't probably 'perfect'.

                    The thing is : 99,+ % clients of all IPSs in the world have just one local LAN after their ISP router.
                    So pfSense as a LAN device of this ISP router like any other device in this ISP LAN, has to obtain a IPv6 in this ISP LAN. This part works pretty well.
                    What is fare more rare : pfSense isn't a 'normal' end device. It's a router, and has its own 'sub' LAN or LANs.
                    So it has to ask 'prefixes', these are blocks /64 or ::1 to ::fffff:ffff:ffff:ffff, for every LAN pfSense has. That part is less well tested, less well implemented. And it all starts with : less well understood.

                    No "help me" PM's please. Use the forum, the community will thank you.
                    Edit : and where are the logs ??

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                    • Bob.DigB Offline
                      Bob.Dig LAYER 8 @crazypotato142
                      last edited by

                      @crazypotato142 said in All IPv6 traffic is being blocked:

                      Shouldn't it work this way

                      Yes. So you might (also) have different problems.

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                      • JKnottJ Offline
                        JKnott @crazypotato142
                        last edited by

                        @crazypotato142 said in All IPv6 traffic is being blocked:

                        I'm just asking to understand the process: Shouldn't it work this way if it's the thing you guys told about?

                        My prefix hasn't changed in almost 7 years, so I don't have much experience to work from. However, I would expect the pfSense LAN interface to show the new prefix and the router advertisements should tell other devices on the LAN what the new prefix is.

                        PfSense running on Qotom mini PC
                        i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel 1 Gb Ethernet ports.
                        UniFi AC-Lite access point

                        I haven't lost my mind. It's around here...somewhere...

                        crazypotato142C 1 Reply Last reply Reply Quote 0
                        • crazypotato142C Offline
                          crazypotato142 @JKnott
                          last edited by

                          I don't know, I still don't think it's a prefix problem because I used it as it is for a long time without a single problem and now I simply can't connect to the internet with it.

                          But I can't see any problem on my settings and my ISP says there's nothing wrong on their side either. I'll just turn my IPv6 network completely off until I figured it out because it really causes my network go crazy.

                          Do you have any recommendations to check or solve?

                          Bob.DigB JKnottJ 2 Replies Last reply Reply Quote 0
                          • Bob.DigB Offline
                            Bob.Dig LAYER 8 @crazypotato142
                            last edited by

                            @crazypotato142 Check the IPv6-addresses closely, are they really using the same prefix or do they differ. It must be the same prefix as pfSense LAN has.

                            In Windows use ipconfig /release6 and then ipconfig /renew6 and watch out for problems.

                            crazypotato142C 1 Reply Last reply Reply Quote 0
                            • crazypotato142C Offline
                              crazypotato142 @Bob.Dig
                              last edited by crazypotato142

                              @Bob.Dig They are like this right now:

                              Photos deleted for privacy

                              Note: I can't ping an IPv6 address over pFsense interface either.

                              Bob.DigB 1 Reply Last reply Reply Quote 0
                              • Bob.DigB Offline
                                Bob.Dig LAYER 8 @crazypotato142
                                last edited by

                                @crazypotato142 The first address already looks wrong. At least the prefix is the same.

                                crazypotato142C 1 Reply Last reply Reply Quote 0
                                • crazypotato142C Offline
                                  crazypotato142 @Bob.Dig
                                  last edited by

                                  @Bob.Dig
                                  pFsense itself can't connect to anything over IPv6 either. I can't use IPv6 ping, not even get into the Update page cuz Netgate has IPv6 addresses for their website.

                                  Bob.DigB JKnottJ 2 Replies Last reply Reply Quote 0
                                  • Bob.DigB Offline
                                    Bob.Dig LAYER 8 @crazypotato142
                                    last edited by

                                    @crazypotato142 said in IPv6 cannot connect to Internet:

                                    pFsense itself can't connect to anything over IPv6 either.

                                    That screams for a big problem, might be your ISP at this point.

                                    crazypotato142C 1 Reply Last reply Reply Quote 0
                                    • crazypotato142C Offline
                                      crazypotato142 @Bob.Dig
                                      last edited by

                                      I'll test it with their default router and keep here updated. Thank everyone for the help.

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                                      • U Offline
                                        Uglybrian
                                        last edited by

                                        @Bob.Dig said in IPv6 cannot connect to Internet:

                                        might be your ISP at this point.

                                        Thats what i have been thinking through out this post.

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                                        • JKnottJ Offline
                                          JKnott @crazypotato142
                                          last edited by

                                          @crazypotato142 said in IPv6 cannot connect to Internet:

                                          pFsense itself can't connect to anything over IPv6 either.

                                          I saw in your settings that you request a prefix only, not a WAN address. You might have to specify your LAN interface as the source address. You use the -s option for that.

                                          PfSense running on Qotom mini PC
                                          i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel 1 Gb Ethernet ports.
                                          UniFi AC-Lite access point

                                          I haven't lost my mind. It's around here...somewhere...

                                          crazypotato142C 1 Reply Last reply Reply Quote 0
                                          • crazypotato142C Offline
                                            crazypotato142 @JKnott
                                            last edited by crazypotato142

                                            @JKnott said in IPv6 cannot connect to Internet:

                                            You might have to specify your LAN interface as the source address. You use the -s option for that.

                                            How do I do that?

                                            Also I didn't do such a thing after we got my IPv6 in this thread
                                            https://forum.netgate.com/post/1217330

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