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    Comcast and ipv6

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

      @slk2k comdcast only supports /64 on residentials. If you have more than one internal subnet pulling ipv6 then you will not get any ipv6 at all. I also have mine setup as follows
      WAN:
      everything unchecked. I am asking for a /64.

      The only internal subnet i have ipv6 enabled on is my internal one for my workstations. All other subnets have ipv6 OFF.

      Once i did this i started getting ipv6 addresses again. Business class you can ask for a much much larger allocation.

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

        @hescominsoon Thanks for the info - this is a classic example of the (lack of) information from Comcast on this. Years ago it was a /56 for everyone, then I heard /64 (as you have done it) and then a /60 (as I have it set up). Maybe I will go post something over in the comcast support channels on dslreports and get a networking person to respond and get the exact info.

        Thank you again for sharing your config!

        H 1 Reply Last reply Reply Quote 0
        • 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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