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    Comcast and ipv6

    Scheduled Pinned Locked Moved IPv6
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    • H
      hescominsoon @slk2k
      last edited by

      @slk2k I am a Comcast partner in my area of Maryland...i had to talk to lvl2 support to get this information. Ironically enough different Comcast regions sometimes do things a bit differently. Try my settings and let me know if it works in your area..:)

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      • JKnottJ
        JKnott @hescominsoon
        last edited by

        @hescominsoon said in Comcast and ipv6:

        comdcast only supports /64 on residentials.

        Why are they so stingy? There are enough global unique addresses available to give every single person on earth over 4000 /48s! Many other ISPs provide a /56 and some /48.

        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...

        rdunkleR 1 Reply Last reply Reply Quote 0
        • rdunkleR
          rdunkle @JKnott
          last edited by

          @jknott I have a client with Comcast in WA. They have residential service. I turned on the dhcp debug, and was able to see the prefix and /60. It has been consistent and stable. The hardest part is the lack of information on Comcast ipv6 in any of their forums. I get the best information from reading in this forum.

          JKnottJ S 2 Replies Last reply Reply Quote 0
          • JKnottJ
            JKnott @rdunkle
            last edited by

            @rdunkle

            Even a /60 is d*mn cheap. I used to use a tunnel that provided a /56 which cost me nothing and Hurricane Electric provides a /48 tunnel, again for free.

            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
            • S
              slk2k @rdunkle
              last edited by

              @rdunkle said in Comcast and ipv6:

              @jknott I have a client with Comcast in WA. They have residential service. I turned on the dhcp debug, and was able to see the prefix and /60. It has been consistent and stable. The hardest part is the lack of information on Comcast ipv6 in any of their forums. I get the best information from reading in this forum.

              Same!

              I do have a question that maybe you can answer - is the ipv6 gateway on the pfsense status "Unknown" and a Link Local Address? Just trying to compare configs to make sure I have it the way comcast needs it.

              Thanks!

              H JKnottJ 2 Replies Last reply Reply Quote 0
              • H
                hescominsoon @slk2k
                last edited by hescominsoon

                @slk2k my gateway on my machine is the link local gateway on the pfsense:
                Default Gateway . . . . . . . . . : fe80::1:1%4

                Doing a trace however works fine..so I do not worry about digging deeper..:)
                tracert etc-md.com

                Tracing route to etc-md.com [2604:4100:2:7:223:aeff:fefd:f06c]
                over a maximum of 30 hops:

                1 <1 ms <1 ms <1 ms 2601:142:8200:29c2:217:54ff:fe02:69bb
                2 7 ms 7 ms 7 ms 2001:558:4061:8::1
                3 9 ms 7 ms 18 ms 2001:558:2f2:122::1
                4 18 ms 14 ms 10 ms 2001:558:340:203f::1
                5 10 ms 9 ms 9 ms te-9-4-ur01.potomac.md.bad.comcast.net [2001:558:340:209::2]
                6 14 ms 12 ms 13 ms 2001:558:340:449::2
                7 15 ms 15 ms 14 ms 2001:558:340:802d::2
                8 15 ms 15 ms 23 ms 2001:558:340:283d::2
                9 15 ms 16 ms 22 ms 2001:559:7bd::b6
                10 15 ms 17 ms 15 ms 2604:4100:2:7:223:aeff:fefd:f06c

                Status
                up
                DHCP
                up Relinquish Lease
                MAC Address
                00:17:54:02:69:b5
                IPv4 Address
                76.100.142.***
                Subnet mask IPv4
                255.255.252.0
                Gateway IPv4
                76.100.140.1
                IPv6 Link Local
                fe80::217:54ff:fe02:69b5%em0
                IPv6 Address
                2001:558:6003:8:94c0:2197:589b:****
                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
                MTU
                1500
                Media
                1000baseT <full-duplex>
                In/out packets
                274242494/112687333 (346.09 GiB/34.46 GiB)
                In/out packets (pass)
                274242494/112687333 (346.09 GiB/34.46 GiB)
                In/out packets (block)
                27401/2 (1.54 MiB/140 B)
                In/out errors
                0/0
                Collisions

                Here's my internal interface:
                IPv4 Address
                192.168.255.1
                Subnet mask IPv4
                255.255.255.0
                IPv6 Link Local
                fe80::1:1%em1.10
                IPv6 Address
                2601:142:8200:29c2:217:54ff:fe02:****
                Subnet mask IPv6
                64
                MTU
                1500
                Media
                1000baseT <full-duplex>
                In/out packets
                106112688/248294854 (33.64 GiB/314.61 GiB)
                In/out packets (pass)
                106112688/248294854 (33.64 GiB/314.61 GiB)
                In/out packets (block)
                8092/0 (839 KiB/0 B)
                In/out errors
                0/0
                Collisions
                0

                Then my computer addy on internal network:
                Connection-specific DNS Suffix . : etc.local
                Description . . . . . . . . . . . : Realtek PCIe GbE Family Controller #2
                Physical Address. . . . . . . . . : 30-9C-23-AB-8A-8E
                DHCP Enabled. . . . . . . . . . . : Yes
                Autoconfiguration Enabled . . . . : Yes
                IPv6 Address. . . . . . . . . . . : 2601:142:8200:29c2:8d28:a236:7d38:**** (Preferred)
                Temporary IPv6 Address. . . . . . : 2601:142:8200:29c2:d181:ed2b:4b0e:**** (Preferred)
                Link-local IPv6 Address . . . . . : fe80::8d28:a236:7d38:**** (Preferred)
                IPv4 Address. . . . . . . . . . . : 192.168.255.10(Preferred)
                Subnet Mask . . . . . . . . . . . : 255.255.255.0
                Lease Obtained. . . . . . . . . . : Monday, December 14, 2020 8:02:23 AM
                Lease Expires . . . . . . . . . . : Monday, December 14, 2020 3:02:23 PM
                Default Gateway . . . . . . . . . : fe80::1:1%4
                192.168.255.1
                DHCP Server . . . . . . . . . . . : 192.168.255.1
                DHCPv6 IAID . . . . . . . . . . . : 254843939
                DHCPv6 Client DUID. . . . . . . . : 00-01-00-01-26-F3-51-93-30-9C-23-AB-8A-8E
                DNS Servers . . . . . . . . . . . : 192.168.255.1
                NetBIOS over Tcpip. . . . . . . . : Enabled
                Connection-specific DNS Suffix Search List :
                etc.local

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                • JKnottJ
                  JKnott @slk2k
                  last edited by

                  @slk2k said in Comcast and ipv6:

                  is the ipv6 gateway on the pfsense status "Unknown" and a Link Local Address?

                  I assume you're referring to the WAN address, when you say unknown. With IPv6, the link local address is often used and a routeable WAN address is actually not needed. Even when there is one, it's probably not being used for routing.

                  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...

                  S 1 Reply Last reply Reply Quote 0
                  • S
                    slk2k @JKnott
                    last edited by

                    @jknott It is the WAN Gateway I was asking about. I understand how it's used. Just the OCD in me to see something not green on the status page! I know that pfsense will use the ipv4 interface to determine next hop vales for the monitoring stats.

                    Capture.JPG

                    JKnottJ 1 Reply Last reply Reply Quote 0
                    • JKnottJ
                      JKnott @slk2k
                      last edited by

                      @slk2k

                      I don't have monitoring enabled. Is there some reason you do? You could disable monitoring IPv6 if that status bothers you. Also, what are you using for the monitor IP? It has to be some working address.

                      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...

                      S 1 Reply Last reply Reply Quote 0
                      • S
                        slk2k @JKnott
                        last edited by

                        @jknott Honestly, I don't think I ever intentionally set anything up for that (nor knew it was an option to disable it either). It's just something that's always been there on the dashboard. I assumed it was pfsense pinging the gateway address and getting the answer (since the gateway is usually given by dhcp on the WAN).

                        I just found the checkboxes to disable it - all good :-)

                        8be775e9-6ceb-4d0d-90d3-7915e64cb8fa-image.png

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