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    Multiple IPv6 Prefix Delegation over AT&T Residential Gateway for pfSense 2.4.5

    Scheduled Pinned Locked Moved IPv6
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    • A
      AiC0315
      last edited by

      I am able to get an IPV6 address on WAN and LAN But when I go to a site to test IPV6 it fails. When I plug directly into the RG it passes the test. Am I missing something?

      TIA

      JKnottJ 1 Reply Last reply Reply Quote 0
      • JKnottJ
        JKnott @AiC0315
        last edited by

        @aic0315

        What failure do you see at the test site?
        Which test site are you using?

        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...

        A 1 Reply Last reply Reply Quote 0
        • A
          AiC0315 @JKnott
          last edited by

          @jknott
          Test-ipv6 gives no results for IPV6
          and IPVG-test says not supported

          JKnottJ 1 Reply Last reply Reply Quote 0
          • JKnottJ
            JKnott @AiC0315
            last edited by

            @aic0315

            Are you sure you have an IPv6 address, other than link local?

            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...

            A 1 Reply Last reply Reply Quote 0
            • A
              AiC0315 @JKnott
              last edited by

              @jknott
              On the interface status page it is showing the link local and an IPV6 address. So, I am assuming so.

              JKnottJ 1 Reply Last reply Reply Quote 0
              • JKnottJ
                JKnott @AiC0315
                last edited by

                @aic0315

                What do you get when you run netstat -r?
                You should see something like this:

                Internet6:
                Destination Gateway Flags Netif Expire
                default fe80::217:10ff:fe9 UG igb0

                Try a packet capture when you try to access test-ipv6.

                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
                • P
                  paul_s
                  last edited by

                  I am getting prefix delegation to my two LAN interfaces. It is working great. However, sometimes the prefixes swap interfaces. Is there a way to configure dhcp6c to prevent that?

                  I have an ATT BGW320 and am using a UniFi USG router. Sorry I don't have a PFsense router. I think I just don't know what the dhcp6c configuration should be to prevent the swapping.

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

                    @paul_s

                    What do you mean swap prefixes? Normally, you assign a prefix ID to each interface.

                    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...

                    P 1 Reply Last reply Reply Quote 0
                    • P
                      paul_s @JKnott
                      last edited by

                      @jknott
                      For instance the prefixes and address might be assigned this way
                      2600:1700:2b60:df9e::1 assigned to eth0
                      2600:1700:2b60:df9f::1 assigned to eth1

                      Then a few days later or after a reboot they might be reversed
                      2600:1700:2b60:df9f::1 assigned to eth0
                      2600:1700:2b60:df9e::1 assigned to eth1

                      Is there a way to keep the assignments consistent? What part of the configuration assigned a particular prefix to an interface?

                      Bob.DigB JKnottJ T 3 Replies Last reply Reply Quote 0
                      • Bob.DigB
                        Bob.Dig LAYER 8 @paul_s
                        last edited by

                        @paul_s Something in the pfSense WebGUI. You can set it up for free...

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

                          @paul_s

                          That sounds like a hardware issue. Any chance you're using USB Ethernet ports.

                          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
                          • P
                            paul_s
                            last edited by

                            Not using USB. The interfaces are integrated in the router.

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

                              @paul_s

                              I have never seen anything like that.

                              I just noticed this:

                              I have an ATT BGW320 and am using a UniFi USG router. Sorry I don't have a PFsense router.

                              So, you're not running pfSense? If not, maybe you should be asking in a UniFi forum.

                              My router is the one described in my sig, which I have been using with pfSense for over 1.5 years and before that, I had a HP compact desktop computer. Before that, I had a Linux based firewall on that HP computer and other computers before that. I have never, ever seen interfaces move. Are eth0 and eth1 associated with the same interface (same MAC) when the prefixes move?

                              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
                              • P
                                paul_s
                                last edited by paul_s

                                @JKnott
                                I have a lot of respect for the members of this forum and have been unable to find the answer at UniFi. I was hoping that someone with experience like you might know the mechanism that assigns the delegated prefixes to a particular interface. Is it dhcp6c or is it radvd or something else? Then I hoped there might be a configuration parameter that might anchor the prefix to an interface.

                                The interfaces are not moving, they retain the same MAC address. The IPv6 prefix changes.

                                thanks for your time.

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

                                  @paul_s

                                  Are you running pfSense or not? If not, you're not likely to find a lot of support here. As I mentioned, I have never seen your situation on multiple computers, with either pfSense or Linux firewalls over twenty years or so. My sole Unifi experience is with my AC-Lite access point.

                                  With pfSense, the prefix will change if you don't select that setting I mentioned. Also, some ISPs mess things up to. But neither of those would cause the problem you're mentioning where the same prefix moves to another port.

                                  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
                                  • P
                                    paul_s
                                    last edited by

                                    @JKnott
                                    As I stated in my first post "I don't have a PFsense router."
                                    As I stated in my last post "thanks for your time"

                                    1 Reply Last reply Reply Quote 0
                                    • T
                                      ttmcmurry @paul_s
                                      last edited by

                                      @paul_s

                                      Have no experience with Unifi - my guess would be there's something being incorrectly set on non-wan interfaces. If your ISP is giving you a /60, then you should be specifying on each internal interface the prefix delegate hint so that internal interfaces assign themselves correctly each time.

                                      What I originally posted in post 1 has a step that refers to this process where the prefix delegation is associated "id-assoc" "pd 1" with the correct interface "hn1" (etc).

                                      The only assumption made with AT&T is they reserve a certain number of networks in their /60 for AT&T use, and the rest are available for delegation.

                                      If UniFi doesn't have a way to associate interfaces to prefix delegation, then you'll get the variability that you're experiencing. Even on PFSense, this has to be done by hand, there's nothing in the GUI that allows admins to configure prefix delegation.

                                      The answer to your other question is the documented method in post #1 is using DHCPv6 (no Router Advertisements) to pull the PD.

                                      1 Reply Last reply Reply Quote 0
                                      • P
                                        paul_s
                                        last edited by

                                        @ttmcmurry

                                        The UniFi router uses the same dhcp6c configuration pfSense uses. My config is below. I have not been able to find out what the "ifid" number is in the id-assoc but the rest of it looks like yours. Perhaps the IPv6 Track Interface Prefix ID you reference is the key. I will try to figure out what that does in pfSense and see if I can translate it to UniFi.

                                        Thanks for the help.

                                        interface eth3 {
                                        send ia-na 0;
                                        request domain-name-servers, domain-name;
                                        send rapid-commit;
                                        send ia-pd 0;
                                        send ia-pd 1;
                                        script "/opt/vyatta/sbin/ubnt-dhcp6c-script";
                                        };

                                        id-assoc na 0 {};

                                        id-assoc pd 0 {
                                        prefix ::/64 infinity;
                                        prefix-interface eth0 {
                                        sla-id 0;
                                        sla-len 0;
                                        ifid 1;
                                        };
                                        };

                                        id-assoc pd 1 {
                                        prefix ::/64 infinity;
                                        prefix-interface eth1 {
                                        sla-id 0;
                                        sla-len 0;
                                        ifid 1;
                                        };
                                        };

                                        T 1 Reply Last reply Reply Quote 0
                                        • T
                                          ttmcmurry @paul_s
                                          last edited by

                                          @paul_s

                                          Far less was needed in pfsense..

                                          id-assoc pd 0 {
                                          prefix-interface hn1 {
                                          sla-id 0;
                                          sla-len 0;
                                          };
                                          };

                                          Pfsense GUI interface configuration allows for a prefix hint, configured on the interface. The hint should correspond to how dhcp6d was configured for that interface.

                                          You're also using ifid of 1 in both your pd associations. Is there a reason why you're overriding the EUI-64 address? I'd imagine this would be left alone so the specified interface (eth1, etc) is considered unless you meant to set the EUI address on two interfaces?

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                                          • P
                                            paul_s
                                            last edited by

                                            @ttmcmurry
                                            I appreciate your help but I think I have to give up on this. UniFi puts too many layers between me and the dhcp6c.conf file. The UniFi GUI creates a vyOS file interpreted by a perl script that generates the dhcp6c.conf file. It appears that since I specified a "host-name" of ::1 in the GUI it created the "ifid" = 1 as a way to set the interface host value to 1 which is what I want.

                                            It would seem that the "sla-id" should append a value to the delegated prefix specifically for the interface but since we have to request /64 from ATT and they are already using 8 of those blocks, I can't figure out how to use the "sla-id" properly. It appears people with Comcast can request a /60, include all the interfaces in PD 0 and tailor the prefix to the interface with "sla-id".

                                            Anyway, I will limp along with almost random prefix assignments until I can replace my UniFi router with pfSense.

                                            Thanks again for the help.

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