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    Where in the interface is an interface's IPv6 prefix delegation (PD) shown

    Scheduled Pinned Locked Moved IPv6
    dhcpv6
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    • GertjanG
      Gertjan @NickyDoes
      last edited by

      @NickyDoes said in Where in the interface is an interface's IPv6 prefix delegation (PD) shown:

      And what about the PD size? For me, DHCPv6 Primary Address Pool shows a /64 for this LAN, but the logs show a /56 from the ISP/tunnel broker.

      The prefix size / (should be) Always a /64

      89850b19-a2bb-4bd4-9900-ed797f99467a-image.png

      @NickyDoes said in Where in the interface is an interface's IPv6 prefix delegation (PD) shown:

      but the logs show a /56 from the ISP/tunnel broker.

      That means that /64-/56=/8 or 256 so you could, in theory, have your pfSense, or other routers, ask for 255 prefixes, which mans you can have 256 LANs with 18 446 744 073 709 551 616 IP addresses.

      No "help me" PM's please. Use the forum, the community will thank you.
      Edit : and where are the logs ??

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      • N
        NickyDoes
        last edited by

        I understand; The ISP allocated IPv6/56, allowing 64-56 subnets, usable as their own networks (i.e. subnets).

        From a usability perspective, for those who are taking on IPv6: I should be able to see the number of subnets allocated without diving into the logs.

        johnpozJ GertjanG JKnottJ 3 Replies Last reply Reply Quote 0
        • johnpozJ
          johnpoz LAYER 8 Global Moderator @NickyDoes
          last edited by

          @NickyDoes said in Where in the interface is an interface's IPv6 prefix delegation (PD) shown:

          I should be able to see the number of subnets allocated without diving into the logs.

          Why? Are you not getting the number you asked for or larger? And you can't assign the number of prefixes you need via tracking? This info isn't something you would normally have to even care about - unless something was wrong..

          I mean why should I care if they give me a /60 or /56 or /48 even if I only need say 5 or 6.. I mean a /60 is what 16 /64s..

          An intelligent man is sometimes forced to be drunk to spend time with his fools
          If you get confused: Listen to the Music Play
          Please don't Chat/PM me for help, unless mod related
          SG-4860 24.11 | Lab VMs 2.7.2, 24.11

          N 1 Reply Last reply Reply Quote 0
          • GertjanG
            Gertjan @NickyDoes
            last edited by

            @NickyDoes said in Where in the interface is an interface's IPv6 prefix delegation (PD) shown:

            The ISP allocated IPv6/56, allowing 64-56 subnets, usable as their own networks (i.e. subnets).

            The IS give you a /56.
            For me, it's my ISP router showing this, and I can see :

            615d00f3-e6b6-4292-a611-537ac5e31a3f-image.png

            So, pfSense has take the 'random' "eb" hex. It could have given anything from '01' to 'ff'.
            The '00' is reserved by the ISP router for it's own LAN, and the pfSense WAN interface has an IPv6 using that prefix '00'

            No "help me" PM's please. Use the forum, the community will thank you.
            Edit : and where are the logs ??

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            • JKnottJ
              JKnott @NickyDoes
              last edited by

              @NickyDoes said in Where in the interface is an interface's IPv6 prefix delegation (PD) shown:

              allowing 64-56 subnets

              Actually, 256 /64 subnets.

              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...

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              • N
                NickyDoes @johnpoz
                last edited by

                @johnpoz my perspective is someone who is figuring out IPv6. There's tons of Reddit and other FUD on whether [insert ISP here] delegates /64 or some other prefix.

                MAny of these posts/recipes/tutorials lead someone new to think a /64 cannot readily be divided into subnets. By 'readily', I mean divide and still firewall effectively. People (including me) are already nervous giving up our IPv4 NAT inherent security blanket. Yes, I've read that the security afforded by NAT is not security per se. It's still scary to start learning about IPv6 and be sure you're not inadvertently exposing machines to the public net.

                From your comment ("why should I care.../60 is what 16 64s"), I presume someone can readily divide their /64 and effectively control access. That's beyond what most tutorial/recipes explain. I've RTM, and am still confused, so I've resorted to searching for more tutorials. I'll try posting more questions here.

                Thanks for the help, as always.

                johnpozJ 1 Reply Last reply Reply Quote 0
                • johnpozJ
                  johnpoz LAYER 8 Global Moderator @NickyDoes
                  last edited by johnpoz

                  @NickyDoes said in Where in the interface is an interface's IPv6 prefix delegation (PD) shown:

                  presume someone can readily divide their /64 and effectively control access

                  No not really - some shit not going to work if you break down a /64, pretty sure slaac min size is a /64 for it to work correctly

                  Why would you need to break down a /64? While technically you can do it, pretty sure it will break parts of IPv6..

                  How many local networks do you have? A /56 is 256 /64s you could have - do you need more than that? I think I have a lot for home - 8.. Which some I could prob get rid of really.. Or I could maybe make a few more if I wanted to segment some stuff even further.. I currently lump a lot of different types iot into same network.. But that is a long freaking way from 256 networks..

                  Get with your ISP then, or use a HE tunnel they give you a /48 which is 65k /64s

                  If you are a decent sized company, not some ma and pa shop - you should prob just get direct from arin for example - /32 is like the min size they give out..

                  Do you have some large campus network where you need more than say a /56 would give you?

                  Even if your isp was being stingy and only gave you a /60, that is 16 /64s - which is quite a lot really for some residential customer.. I mean I have my network pretty freaking segmented and I have 8, and couple of those are just test networks, etc.

                  An intelligent man is sometimes forced to be drunk to spend time with his fools
                  If you get confused: Listen to the Music Play
                  Please don't Chat/PM me for help, unless mod related
                  SG-4860 24.11 | Lab VMs 2.7.2, 24.11

                  N 1 Reply Last reply Reply Quote 0
                  • N
                    NickyDoes @johnpoz
                    last edited by

                    @johnpoz ok, I'm making this more confusing because I'm working to learn IPv6 practices thoroughly, but not professionally. I was attempting to share points of confusion as I learn and implement IPv6.

                    My situation: I'm primarily a homelab, with a minor professional component. Google Fi residential is the ISP, providing one dynamic IPv4 and a /56 PD. I have internal IPv4-only networks for home and for work. A 3rd net is for IPv6 testing. I have now verified that my ISP is granting a /56 PD, which is plenty large.

                    JKnottJ johnpozJ 2 Replies Last reply Reply Quote 0
                    • JKnottJ
                      JKnott @NickyDoes
                      last edited by

                      @NickyDoes said in Where in the interface is an interface's IPv6 prefix delegation (PD) shown:

                      I have now verified that my ISP is granting a /56 PD, which is plenty large.

                      Some provide a /48, which is huge!

                      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...

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                      • johnpozJ
                        johnpoz LAYER 8 Global Moderator @NickyDoes
                        last edited by

                        @NickyDoes yeah a /56 is lot of /64s for testing and playing with ;)

                        Best practice is /64 for any segment you want to break out.. Even if it only has a couple of devices on it.. It seems insane when you first start playing with Ipv6 to be honest.. Since a /64 is so freaking huge when it comes to how many IPs..

                        An intelligent man is sometimes forced to be drunk to spend time with his fools
                        If you get confused: Listen to the Music Play
                        Please don't Chat/PM me for help, unless mod related
                        SG-4860 24.11 | Lab VMs 2.7.2, 24.11

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