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    Comcast and ipv6

    Scheduled Pinned Locked Moved IPv6
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    • 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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