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    xfinity, netgear cm1000 and ipv6 problems.

    Scheduled Pinned Locked Moved IPv6
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    • MikeV7896M
      MikeV7896
      last edited by

      It's definitely not a bug... I personally used pfSense with Comcast and had no issues with IPv6 over 5+ years. What are your WAN IPv6 settings?

      For Comcast, they should be something like...

      • IPv6 Configuration Type: DHCPv6
      • Use IPv4 connectivity as parent interface: Pretty sure this can be set either way. If checked, IPv4 must be up and running before IPv6 is attempted.
      • Request only an IPv6 prefix: Unchecked recommended; will work either way. If checked, WAN will only have a link-local IPv6 address.
      • DHCPv6 Prefix Delegation size: 60 if residential service, 56 if business
      • Send IPv6 prefix hint: Checked
      • Do not wait for a RA: Checked

      And then for your LAN(s), IPv6 Configuration Type would be "Track Interface", and the IPv6 settings would be "WAN", and pick a prefix ID.

      The S in IOT stands for Security

      H 3 Replies Last reply Reply Quote 0
      • H
        hescominsoon @MikeV7896
        last edited by

        @virgiliomi said in xfinity, netgear cm1000 and ipv6 problems.:

        It's definitely not a bug... I personally used pfSense with Comcast and had no issues with IPv6 over 5+ years. What are your WAN IPv6 settings?

        For Comcast, they should be something like...

        • IPv6 Configuration Type: DHCPv6
        • Use IPv4 connectivity as parent interface: Pretty sure this can be set either way. If checked, IPv4 must be up and running before IPv6 is attempted.
        • Request only an IPv6 prefix: Unchecked recommended; will work either way. If checked, WAN will only have a link-local IPv6 address.
        • DHCPv6 Prefix Delegation size: 60 if residential service, 56 if business
        • Send IPv6 prefix hint: Checked
        • Do not wait for a RA: Checked

        And then for your LAN(s), IPv6 Configuration Type would be "Track Interface", and the IPv6 settings would be "WAN", and pick a prefix ID.

        Some background on myself: I am a comcast partner and, in my area at least, comcast is not giving out larger than a /64. i've been able to confirm this at multiple residential clients of mine. yes i know it's a ipv6 standard thing..but who says isp's always follow the rules?

        As for the settings...that's what i had them at when things stopped working. I turned ipv6 totally off in all areas until I could get a response. I'll rebuild them back to the above configuration and try it again.

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        • H
          hescominsoon @MikeV7896
          last edited by hescominsoon

          @virgiliomi
          ok here's what i have now:
          IPv4 Address
          76.100.142.xxx
          Subnet mask IPv4
          255.255.252.0
          Gateway IPv4
          76.100.140.xxx
          IPv6 Link Local
          fe80::217:54ff:fe02:69b5%em0
          IPv6 Address
          2001:558:6003:8:51ce:81db:6dce:xxxx
          Subnet mask IPv6
          128
          Gateway IPv6
          fe80::201:5cff:fe86:a446
          DNS servers
          127.0.0.1
          9.9.9.9
          149.112.112.112
          2620:fe::fe
          2620:fe::9
          I have enabled track interface on one internal interface. tried both id 0 and id 1. Neither of them have gotten me an ipv6 allocation:

          noipv6.png

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          • H
            hescominsoon @MikeV7896
            last edited by

            @virgiliomi
            right now i am going to disable ipv6 again. i will hook up my laptop and post what i get there. I have some packet captures i can let you see as well. If you'd like to see them I'll pm you the link to where i have them stored..:)

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            • MikeV7896M
              MikeV7896
              last edited by MikeV7896

              Keeping in mind that most people have a gateway (modem + router in one) rather than a separate modem and router, they will probably only ever see a /64. That's what needs to be used on a LAN, and those gateways don't usually support more than one LAN. But pfSense connected to a modem (not a gateway, unless it's in bridge mode) should be able to request a prefix that gets you multiple /64's, so you can set up multiple networks, each with their own /64.

              Clearly you have a WAN address... so DHCPv6 is working. Requesting a /60 prefix on your WAN will work regardless of your service. If you have business service and need more than 16 /64's, you could request a /56. Your internal networks should be Track Interface > WAN, and each should use a different prefix ID.

              The S in IOT stands for Security

              H 2 Replies Last reply Reply Quote 0
              • H
                hescominsoon @MikeV7896
                last edited by

                @virgiliomi yes i have all of those setup in the interfaces. i do NOT have an ipv6 wan address...it only get one when i plug a laptop directly into the cm1000..the pfsense box is NOT pulling an ipv6 address at all.

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                • H
                  hescominsoon @MikeV7896
                  last edited by

                  @virgiliomi so i tried re-enabling ipv6 and i got an ipv6 address on wan..the instant i enabled track interface it dropped the ipv6 on the wan and refuses to pull ipv6 again.

                  MikeV7896M 1 Reply Last reply Reply Quote 0
                  • MikeV7896M
                    MikeV7896 @hescominsoon
                    last edited by

                    @hescominsoon Make sure your LAN is set to Track Interface, then go to Status > Interfaces and do a Release then Renew on your WAN interface and see if IPv6 returns.

                    The S in IOT stands for Security

                    H 1 Reply Last reply Reply Quote 0
                    • H
                      hescominsoon @MikeV7896
                      last edited by

                      @virgiliomi they are..and tried this more than once..nothing. If i plug a laptop into the modem ipv6 works perfectly.

                      MikeV7896M 1 Reply Last reply Reply Quote 0
                      • MikeV7896M
                        MikeV7896 @hescominsoon
                        last edited by

                        @hescominsoon

                        I'm not sure what to say other than maybe try Comcast's forums or other ISP community sites on the internet for settings that will work. It's been over a year since I had Comcast service, but I used pfSense with IPv6 and had no issues for over four years using the settings I provided earlier.

                        If you have a gateway (modem+router) in gateway mode, pfSense won't work for IPv6 because the gateway will acquire a single /64 for its own use. I don't know if their gateways will sub-delegate additional /64's or not.

                        If you have a gateway that is in bridge mode, or have just a regular modem (I used both Motorola/Zoom and Arris modems over my time on Comcast), you should be able to request a /60 unless they've changed things since I left.

                        The S in IOT stands for Security

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