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    Comcast Native IPv6

    Scheduled Pinned Locked Moved IPv6
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    • W
      wcktklwn
      last edited by

      Has anyone tried using IPv6 on business class internet from Comcast?

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      • D
        darkcrucible
        last edited by

        You can get native IPv6 with business class if you do not have static IPs. I'm not sure about which modems will work with it but I do know the SB6120 will work. One last thing I can think of is that you must be in an area where the CMTS is from Arris in order to get IPv6.

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        • W
          wcktklwn
          last edited by

          I do not have any static IPs and I am running a SB6121. Where can I see if I am in the area for CMTS is from Arris?

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          • D
            darkcrucible
            last edited by

            wcktklwn, your settings look to be the same that I'm using. Native dual stack works well for me with Comcast. The /128 address you get is for the WAN and the /64 subnet is for the LAN. If the LAN interface of pfsense isn't getting an address then something may have gone wrong.

            What snapshot are you using? You may need to upgrade to the latest.

            If you have ipv6 connectivity on the WAN that isn't through a tunnel then you're probably in an Arris area. You can look up the CMTS mac address in the modem log page. Mine fills up with random warnings and errors that mention the CMTS mac address. Take the first half of the mac address and do a OUI lookup (just google it if you're unfamiliar)

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            • W
              wcktklwn
              last edited by

              darkcrucible,

              The problem I am getting is that I am receiving a /64 address on my WAN not a /128 and that is what confuses me. I started with using the snapshots at http://snapshots.pfsense.org and when that failed I tried doing a playback gitsync master and that didn't help. Both of which were in the last couple of days.

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              • W
                wcktklwn
                last edited by

                Here are some screenshots to see if this helps anyone.

                I checked into my CMTS mac and it turns out to be a Cadant Inc mac address. After some research Cadant Inc was acquired by Arris

                IPv6.jpg
                IPv6.jpg_thumb
                IPv6-2.jpg
                IPv6-2.jpg_thumb
                IPv6-3.jpg
                IPv6-3.jpg_thumb

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                • johnpozJ
                  johnpoz LAYER 8 Global Moderator
                  last edited by

                  Mine is the same "Cadant" Im on a sb6120

                  Like I said, they are not as stable as they think they are..  I wouldn't mind the low ping times your showing there vs my tunnel times.  So maybe this weekend I will give it a go again.

                  But I don't think your issue is pfsense related to be honest.  When you plug a box directly into your modem – do you get your /128? vs your routed /64

                  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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                  • D
                    darkcrucible
                    last edited by

                    Check this out: http://www.dslreports.com/forum/r27186774-IPv6-Evidence-of-Comcast-IPv6-CPE-Dual-Stack-CPE-and-CPEPD-

                    The 2001: address that you see is your /128. When I say /128 I mean that you were given a subnet of usable address(es) in a /128. With DHCP6-PD, you are additionally given a /64 subnet. This /64 subnet should start with a 2601: In my situation, pfsense assigns itself something from the /64 subnet on the LAN and starts offering that subnet on the LAN. Something has gone wrong with this part for you.

                    I notice on your gateway page you have multi-wan? I don't have any experience with that so my only suggestion is to disable it temporarily and see if the the prefix delegation starts working for your LAN.

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                    • W
                      wcktklwn
                      last edited by

                      I tried disabling that interface and it doesn't seem to make any difference.

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                      • B
                        blackbrayn
                        last edited by

                        I have the same issue , meaning i only get the /64 asigned to the wan , and can't see the /128 , lan has no ipv6 .
                        Same config - dhcpv6 /track interface -prefix id 0

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                        • W
                          wcktklwn
                          last edited by

                          I managed to get this working. I believe I snort had something to do with this. Once I removed it and did a upgrade to pfsense the problem went away.

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                          • D
                            databeestje
                            last edited by

                            We just checked in a fix for this, get a snapshot dated january 6th or later please.
                            We changed the DHCP6 client back to the WIDE client which should work better.

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