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    Sharing a single /64

    Scheduled Pinned Locked Moved IPv6
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    • DerelictD
      Derelict LAYER 8 Netgate
      last edited by

      Get a /56 or a /48. Use /64s on the interfaces. It is not pfSense. It is IPv6.

      Chattanooga, Tennessee, USA
      A comprehensive network diagram is worth 10,000 words and 15 conference calls.
      DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
      Do Not Chat For Help! NO_WAN_EGRESS(TM)

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      • V
        vitaprimo
        last edited by

        Thanks, that's what I was afraid of. It's just a /64 is already huge. These IPv6 designers went overboard.

        Thanks again, I'll start deploying right away. 🤓

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        • DerelictD
          Derelict LAYER 8 Netgate
          last edited by

          Stop sweating it. Every network segment gets a /64. You never have to worry about interface subnet size again.

          Chattanooga, Tennessee, USA
          A comprehensive network diagram is worth 10,000 words and 15 conference calls.
          DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
          Do Not Chat For Help! NO_WAN_EGRESS(TM)

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          • johnpozJ
            johnpoz LAYER 8 Global Moderator
            last edited by

            Exactly.. Think of /64 as today you think of a /24 or smaller.. /64 is the prefix you put on an interface.. Be it your going to have 4 devices or 400 devices on this network its a /64 you would use.  Shoot even if was a point to point where you would normally use a /30 in ipv4 you would use a /64 in ipv6..

            Unlike say a /24 in ipv4 you would not subnet a /64 that is the smallest you go.. If you need more networks then you need a /60, /56 /48 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 2.8, 24.11

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            • V
              vitaprimo
              last edited by

              I'm setting up HE.net and already got the /48 block; I have a doubt though, does the GIF interface stays the same or do I need to reconfigure it with the /48 info, or, does that go in the DHCP/RA section?

              Thanks for your help, again!

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              • DerelictD
                Derelict LAYER 8 Netgate
                last edited by

                the GIF stays the same. You assign /64s out of the /48. You have 65536 of them to play with.

                Chattanooga, Tennessee, USA
                A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                • V
                  vitaprimo
                  last edited by

                  Thanks, this is so cool. 😃 💾

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                  • JKnottJ
                    JKnott
                    last edited by

                    @vitaprimo:

                    Thanks, that's what I was afraid of. It's just a /64 is already huge. These IPv6 designers went overboard.

                    Thanks again, I'll start deploying right away. 🤓

                    It's not huge, compared to the IPv6 address space.  ISPs hand out /56 or /48 prefixes.  That's 256 or 65536 /64s.  That's still puny compared to what's available.  At the moment, only 1/8th of the entire IPv6 address space is assigned to global address use.  Over 3/4s is not assigned for anything.  Even then, there are enough /48s for every single person on earth to have over 4000 of them.  So, lets have no more of this nonsense about splitting a /64.

                    Incidentally, a /64 contains the entire IPv4 address space squared!.

                    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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                    • JKnottJ
                      JKnott
                      last edited by

                      @Derelict:

                      the GIF stays the same. You assign /64s out of the /48. You have 65536 of them to play with.

                      Can pfSense assign the full /48, up to FFFF?  On my system, the prefix IDs only go up to FF.  But I only have a /56 prefix.

                      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
                        last edited by

                        Yeah 65K /64 pretty much enough for as many networks you would ever need to create even if you think of a /64 as overkill with the number of address that can be on it..  And if not then get a /32 ;) This can be a issue to get your head around for sure.. It takes a bit to forget your ipv4 thinking - to me /64 with how many addresses that can be on it seems so wasteful..  But in the big picture with how big ipv6 space it really is almost infinite… Which I am sure that is what they thought of the ipv4 space when they started - and look how that turned out..

                        But compared to how much space there is on ipv4, ipv6 is so freaking big!!! I mean big!!! that while using a /64 for a couple of devices might seem wasteful - that is how its designed, and there will never be an issue for IP addresses - not for your great grandkids for sure even ;)  If not great great great, 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 2.8, 24.11

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                        • DerelictD
                          Derelict LAYER 8 Netgate
                          last edited by

                          You need a /48 to delegate /56 to other sites which is as small as anyone should go. You need a /56 to delegate /60.

                          Chattanooga, Tennessee, USA
                          A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                          DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                          Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                          • JKnottJ
                            JKnott
                            last edited by

                            And if not then get a /32 ;) This can be a issue to get your head around for sure.

                            There are enough IPv6 Global Unicast Addresses to give everyone on earth a /36 and have lots left over!

                            But in the big picture with how big ipv6 space it really is almost infinite… Which I am sure that is what they thought of the ipv4 space when they started - and look how that turned out..

                            According to Vint Cerf, one of the creators of the Internet.  IPv4, with 32 bit addresses, was just intended to be a proof of concept, with the real version having a much larger address space.  Unfortunately, it escaped.

                            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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                            • DerelictD
                              Derelict LAYER 8 Netgate
                              last edited by

                              Can pfSense assign the full /48, up to FFFF?  On my system, the prefix IDs only go up to FF.  But I only have a /56 prefix.

                              If you get a /48 PD you can set the track interface prefix ID from 0 to ffff. What is displayed and accepted as input there is dynamic and is dependent on the size of the PD. (A /60 shows 0 - f)

                              pfSense running with thousands of defined interfaces is another matter.

                              Chattanooga, Tennessee, USA
                              A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                              DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                              Do Not Chat For Help! NO_WAN_EGRESS(TM)

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