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    Setup Dual Stack with NAT on v4

    Scheduled Pinned Locked Moved IPv6
    22 Posts 6 Posters 3.1k Views
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    • DerelictD
      Derelict LAYER 8 Netgate
      last edited by

      A /48 is the minimum allocation for such a thing. If someone in a datacenter asks for it, they should immediately get it. Maybe he's subdividing it into /56s over VPN. There are only 256 of those. There is zero reason for the ISP to care. A "X-Small" ISP allocation is a /32, or 64K /48s.

      Again, if it is "here's a /64 for your VPS web server. Have fun," then it is the wrong product for the use case.

      There is zero reason not to do it.

      It is only 64K interfaces.

      ![Screen Shot 2018-02-19 at 3.44.10 AM.png](/public/imported_attachments/1/Screen Shot 2018-02-19 at 3.44.10 AM.png)
      ![Screen Shot 2018-02-19 at 3.44.10 AM.png_thumb](/public/imported_attachments/1/Screen Shot 2018-02-19 at 3.44.10 AM.png_thumb)

      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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      • S
        SurtursRevenge
        last edited by

        I asked the datacenter provider.

        I can get oen /56 IPv6 Subnet. But not more.

        So how would I need to setup the pfsense to get public v6 to my VMs.
        Because there is no DHCP I need to do this static

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        • NogBadTheBadN
          NogBadTheBad
          last edited by

          @SurtursRevenge:

          I can get oen /56 IPv6 Subnet. But not more.

          How they're handing out IPv6 address space is borked.

          https://www.ripe.net/support/training/material/lir-training-course/LIR-Training-Handbook-Appendices/IPv6Chart_2015.pdf

          Andy

          1 x Netgate SG-4860 - 3 x Linksys LGS308P - 1 x Aruba InstantOn AP22

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          • johnpozJ
            johnpoz LAYER 8 Global Moderator
            last edited by

            While they should prob just give a /48 a /56 will work just fine - as long as it is actually ROUTED to you and not just putting the /56 on their interface connected to you… Have seen that a lot around here..

            You should get a /64 that you use as transit.. That you would put on your wan interface of pfsense, then just break that /56 into /64's that you put on your interfaces/vlans for your networks behind pfsense.

            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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            • JKnottJ
              JKnott
              last edited by

              You should get a /64 that you use as transit.

              On IPv6, the "transit" network is normally link local.  The global is used to access the router WAN interface for management, but nothing else.  If you don't enable remote management via the WAN interface, that address serves no useful purpose.  Unlike IPv4, link local addresses are normally used for routing on IPv6.

              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

                While I agree that sure you can use link local for your transit.. I don't agree with that being a good option.  There is ZERO reason not to make it a actual viable address.  For starters so that your traceroute is valid.

                I can use rfc1918 as my transit to route public IPv4 as well - doesn't make it a good idea.

                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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                • K
                  kpa
                  last edited by

                  On IPv6 a link-local gateway address is what you get more often than not and it's completely valid and according to the specifications.

                  This is on my Mac:

                  
                   route -n get -inet6 default
                     route to: ::
                  destination: ::
                         mask: default
                      gateway: fe80::21b:21ff:fea6:4244%en0
                    interface: en0
                        flags: <up,gateway,done,prcloning>recvpipe  sendpipe  ssthresh  rtt,msec    rttvar  hopcount      mtu     expire
                         0         0         0         0         0         0      1500         0</up,gateway,done,prcloning> 
                  

                  That's configured with plain SLAAC.

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                  • johnpozJ
                    johnpoz LAYER 8 Global Moderator
                    last edited by

                    Again I hear you… So? Read https://tools.ietf.org/html/rfc7404

                    It clearly goes over the advantages and disadvantages to doing it that way..  There are many ways to skin a cat, I don't like skinning the cat that way because it has issues that I would rather not deal with...

                    Its not like you have to worry about running out of space by using up a /64 for your transit..

                    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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                    • JKnottJ
                      JKnott
                      last edited by

                      While I agree that sure you can use link local for your transit.. I don't agree with that being a good option.

                      Take a look at your routing table.  You'll see it uses link local, not routeable addresses  In fact, on point to point links, you don't even need an IP address at all, just the link.  On IPv6, routing via link local addresses is the default, not an option.

                      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

                        @johnpoz:

                        Again I hear you… So? Read https://tools.ietf.org/html/rfc7404

                        It clearly goes over the advantages and disadvantages to doing it that way..  There are many ways to skin a cat, I don't like skinning the cat that way because it has issues that I would rather not deal with...

                        Its not like you have to worry about running out of space by using up a /64 for your transit..

                        Unless you specifically configure using otherwise, you will normally be using link local.  It happens with pfSense and it happens with routing protocols such as OSPF.  The only purpose of the interface IP address in routing is to determine which link is used.  When you look through the routing table, you will see the IP address will resolve to an interface, which is how routing takes place.

                        Now, there is nothing wrong with assigning a routeable address to an interface, for things like remote managment, ping, traceroute etc., but it normally will not have any purpose in the routing function.

                        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

                          Again I hear you… So? Read https://tools.ietf.org/html/rfc7404

                          I just did.  That article points out why you'd need a routeable address for management purposes, not routing.  Given that any interface that has a routeable address would also have a link local address (even my OpenVPN tunnel has a link local address), it's not an either/or situation.  Use a routeable address for management and link local for routing.  Regardless, a routeable address is not necessary for routing in IPv6.  Incidentally, some of the things in that article might make a case for using ULA and not global addresses.  ULA provides a routeable address that's not exposed externally.

                          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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