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    Ipv6 comcast

    Scheduled Pinned Locked Moved IPv6
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    • C
      casoah
      last edited by

      Yeah it's here. Works fine with openwrt.

      It actually used to work on pfsense on some of the testing builds, but only for a few days.

      I guess nobody really needs ipv6 but I just kind of want it lol.

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      • R
        razzfazz
        last edited by

        If you set your delegation size to anything other than /64, make sure you enable "send prefix hint" as Comcast will only give you a /64 otherwise.

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        • C
          casoah
          last edited by

          I'm using a 64 now, rebooted pfsense and the modem.
          Still doesn't work.

          On status->gateways

          it shows WAN_DHCP6 and  fe80::201:5cff:xxxx:xxxx (i put those x's)
          and that looks valid to me

          not sure why it's not working for the pc's though

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          • J
            JacktheSmack
            last edited by

            Comcast recently changed their IPV6 connectivity. Before I was able to use DHCP on WAN, but now I had to twitch it to 6to4 Tunnel. LAN can still be Track Interface.

            I found this out when I plugged directly into my modem, and ran ipconfig /all in Windows. It said it was using a 6to4 tunnel for ipv6.

            It may take a while for ipv6 connectivity to work on the computers on the network. Despite my router being able to ping ipv6.google.com, my computer wasn't able to load ipv6.google.com. I gave up and tried again a few hours later, without making any changes, and it was working.

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            • R
              razzfazz
              last edited by

              That is definitely not true for Comcast in general; my native v6 connection continues to work just fine, without any 6to4 tunneling.

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              • P
                priller
                last edited by

                Yup … Nothing changed here. Comcast native dual-stack IPv6 is working just fine.

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                • J
                  jcyr
                  last edited by

                  ditto…

                  IPV6 Test: http://ipv6-test.com

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                  • J
                    JacktheSmack
                    last edited by

                    @jcyr:

                    IPV6 connectivity is lost upon modem reset and does not recover.

                    Are you saying if someone unplugs the power cable to their modem, and plugs it back in, it no longer supports ipv6? Can you elaborate? I recently lost ipv6 around the time I got a new IP address after changing the spoofed mac address on my pfsense box.

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                    • J
                      jcyr
                      last edited by

                      No, that quote was about temporary loss of IPV6 connectivity after a modem reset. Temporary in the sense that a pfSense reboot is required to restore it. It's a known pfSense 2.1 flaw…

                      IPV6 Test: http://ipv6-test.com

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                      • J
                        JacktheSmack
                        last edited by

                        You guys were right, I tried multiple settings with WAN IPV6 until I just unchecked everything under DHCP v6 client configuration. Now it works fully. I don't know what changed, but before I could request just the prefix.

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                        • R
                          ropeguru
                          last edited by

                          I am having this same issue. I have tried every combo I can think of and still cannot get an IPv6 address on the LAN side. I get a WAN ipv6 address and can ping from the pfsense box to the Netgear IP and to the outside world.

                          Any ideas??

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                          • D
                            Darkk
                            last edited by

                            I am on Comcast as well and they support IPv6.  I too have problems getting it to work correctly so disabled it for now.  Is this something by region?  I am Northern California region area if that makes any difference?

                            What I did not like if I allow each device to be assigned IPv6 that can be seen on the internet by disabling the DHCP v6 for the LAN.  Granted each device have it's own firewall but I rather this be NAT'D same way as IPv4.  This been long discussed on various websites about this.

                            Any thoughts?

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                            • C
                              clinta
                              last edited by

                              I found that block bogon network was breaking my IPV6 on comcast. It was blocking the dhcpv6 replies from getting to the router.

                              Darkk, your machines having public IPV6 addresses is how IPV6 is supposed to work. That's the entire point. But they are still firewalled by pfsense, you do not need NAT to have firewalling.

                              Incoming connections to ipv6 addresses behind your pfsense firewall will be blocked by pfsense, you still have to open the ports you need. But now because you're free of nat, you don't have the previous limitations of one service per port on your single wan IP. You can open port 80 for a webserver for example on several different servers, and because they each have public IPV6 addresses, those rules don't overlap.

                              Being free of NAT is wonderful.

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                              • P
                                priller
                                last edited by

                                @clinta:

                                I found that block bogon network was breaking my IPV6 on comcast. It was blocking the dhcpv6 replies from getting to the router.

                                Same here.

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                                • R
                                  razzfazz
                                  last edited by

                                  @Darkk:

                                  What I did not like if I allow each device to be assigned IPv6 that can be seen on the internet by disabling the DHCP v6 for the LAN.  Granted each device have it's own firewall but I rather this be NAT'D same way as IPv4.  This been long discussed on various websites about this.

                                  Any reasonably modern device should support IPv6 privacy extensions, and will use a random temporary address (that also changes over time) for any outbound communication, not the SLAAC-assigned one that's derived from its MAC address. This provides effectively provides the same degree of privacy as NAT in IPv4, except that instead of seeing connections from a bunch of different ports on a single dynamically assigned IP, the outside world now sees connections from a bunch of random addresses in a dynamically allocated prefix.

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                                  • J
                                    jcyr
                                    last edited by

                                    Any reasonably modern device should support IPv6 privacy extensions, and will use a random temporary address (that also changes over time) for any outbound communication, not the SLAAC-assigned one that's derived from its MAC address.

                                    Unfortunately this renders any per host bandwidth controls available using dummynet pipes unusable. In many ways I've found IPV6 less flexible (useful) than IPV4.

                                    IPV6 Test: http://ipv6-test.com

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                                    • C
                                      casoah
                                      last edited by

                                      Any plans for patches to fix ipv6? I tried unblocking bogon, still no go.

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                                      • C
                                        clinta
                                        last edited by

                                        @jcyr:

                                        Any reasonably modern device should support IPv6 privacy extensions, and will use a random temporary address (that also changes over time) for any outbound communication, not the SLAAC-assigned one that's derived from its MAC address.

                                        Unfortunately this renders any per host bandwidth controls available using dummynet pipes unusable. In many ways I've found IPV6 less flexible (useful) than IPV4.

                                        I'm not familiar with dummynet, but from a general networking perspective if your router that's limiting bandwidth is on the same lan as the device you want to limit you can see it's mac address and should be able to use that for unique host identification and control.

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                                        • J
                                          jcyr
                                          last edited by

                                          Dummynet does not support rate/limiting per mac address. It is a layer three pipe.

                                          IPV6 Test: http://ipv6-test.com

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                                          • A
                                            awesomekyle
                                            last edited by

                                            I'm having the same issue with my Comcast IPv6. I used to use an Airport Extreme as my router and connected directly to my modem from two different PCs and I've had perfect native IPv6 compatibility for months now (I'm in Oregon). Today I tried using pfSense, but it's only working for IPV4.

                                            I've tried every option I can think of under my WAN connection, but nothing seems to change it. The problem is that pfSense just doesn't get an IPv6 address from Comcast while my other router has no problem.

                                            I'm not sure if this is related, but every other router and computer I've tried has always gotten a 24.21.XXX.XXX IP address. pfSense is getting me a 76.27.XXX.XXX IP address. My connection still works fine (hence being able to post this), I just thought that it was odd.

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