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    Got a /112, can't use it on WAN but SLAAC works and I do get routed /112 packets

    Scheduled Pinned Locked Moved IPv6
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    • JKnottJ
      JKnott
      last edited by

      Does your ISP use DHCPv6?  If so, configure pfSense for DHCPv6 on the WAN side and set up the LAN side to track the WAN interface.

      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

        That is strange.  With a /112, SLAAC will not work.  You're limited to DHCPv6 or static configuration.  Incidentally, a /64 is the smallest network an ISP is supposed to hand out.  Perhaps you could tell your ISP they're violating the specs (RFC 7421 among others).

        "As a result, RFC 4291 describes a method of forming interface
          identifiers from IEEE EUI-64 hardware addresses [IEEE802], and this
          specifies that such interface identifiers are 64 bits long.  Various
          other methods of forming interface identifiers also specify a length
          of 64 bits.  The addressing architecture, as modified by [RFC7136],
          states that:

        For all unicast addresses, except those that start with the binary
              value 000, Interface IDs are required to be 64 bits long.  If
              derived from an IEEE MAC-layer address, they must be constructed
              in Modified EUI-64 format."

        Since the interface ID is 64 bits, the local network prefix can only be /64.

        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

          use of /112 is borked and not valid.. If isp is handing out /112 they are doing it wrong!!

          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

            Wow.  I have done a lot of work in data centres and colo sites and never heard of that.  Normally, a customer would get their own fibre & IP address blocks from the ISP.  IPv6 addresses are so plentiful there's absolutely no reason to share a /64.  It's so easy to get a /48.  Get one of those and split it up.

            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

              "give us a technical reason why, as this is non-standard".

              Well, there's RFC 7421 as I mentioned above, where it states the interface ID is supposed to be 64 bits.

              I'd set it up with NAT and IP aliases if needed, but I never had to do that nor do I really want to.

              No, you don't want NAT.  It's a hack to get around the IPv4 address shortage.

              Maybe I should just come up with a technically sound story on why this /122 is crap and I'd like a /48 instead

              How are they delivering that /112 to you?  Is it actually routed from their main block?  Or is it just a block of addresses, which you are allowed to use.  If so, then you don't want a router, just a firewall.

              I suppose, if all else fails, you can get your own /48 from Hurricane Electric and run a 6in4 tunnel via IPv4.

              Perhaps you should ask them why they're so stingy with something as plentiful as IPv6 addresses.  After all, Hurricane Electric will give you a /48 for free.  I had a free /56 via tunnel for 6 years from another tunnel broker.

              BTW, there are enough /48s to give every person on earth well over 4000 each.  There's absolutely no reason why a /64 has to be split, other than gross incompetence.

              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

                without a /64 stuff like nd and whole bunch of other stuff breaks.. While sure you can use smaller prefixes in routing.. Hosts need /64 so why if they want to use /112 as a transit between their routers fine.  But you as a end user that will have hosts on an IPv6 network you need to be able to use /64's

                https://tools.ietf.org/html/rfc5375#section-3

                Using a subnet prefix length other than a /64 will break many
                  features of IPv6, including Neighbor Discovery (ND), Secure Neighbor
                  Discovery (SEND) [RFC3971], privacy extensions [RFC4941], parts of
                  Mobile IPv6 [RFC4866], Protocol Independent Multicast - Sparse Mode
                  (PIM-SM) with Embedded-RP [RFC3956], and Site Multihoming by IPv6
                  Intermediation (SHIM6) [SHIM6], among others.  A number of other
                  features currently in development, or being proposed, also rely on
                  /64 subnet prefixes.

                So they say /112 is their standard??  What moron came up with that??  Clearly they do not understand how ipv6 works even at a basic level and are trying to apply ipv4 thinking to ipv6 space..  All you should have to do is point to the freaking rfcs on why assigning you a /112 is just broken from every single technical aspect.. There is no freaking reason to not adhere to the rfc's when it comes to breaking up the ipv6 prefix's..  More then likely they should of gotten atleast a /32 which is the default block an isp would of gotten from their regional address registry, ARIN for example..  that is default block and your talking 64K /48's they could use..  For what possible reason would thy have to use /112's???  Other than their network architect is an idiot? If they did not get enough ipv6 space to provide proper prefixes to their customers and to use within their dc then they need to get more..

                If your desire is to use ipv6 and this location/dc can not provide with the proper way to do it - then I would be looking to move elsewhere to be honest. If they can not get some as basic as ipv6 assignment correct what else are they just doing all F'd up??

                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

                  I would not waste one minute trying to get that nonsense to work.

                  I would get a properly-routed /48 or move.

                  Nobody needs to "justify" a need for a /64 on an interface, or a /48 (OK, fine, a /56) in a datacenter. It just is.

                  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

                    Nobody needs to "justify" a need for a /64 on an interface, or a /48 (OK, fine, a /56) in a datacenter. It just is.

                    Depending on his needs, a /64 may be plenty.  However, that site has no business splitting a /64.  SLAAC requires a /64 to 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

                      If there's only one host, then perhaps they should just let you use one address of a /64 that's shared with others.  Unless you have multiple devices, there's no real need for an address block.  Once you have an address, you just have to configure the DNS to point to it.  Either way, this /112 nonsense is causing problems.

                      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

                        So I have a few 15$ a year vpses.. And they give me a full /64 on each of them..  They are in the same data center..  So does not matter if its 1 box with 1 connection or not.. Now on 2 of them only use 1 ipv6, since all that I need for that.. But I can assign as many ipv6 out of that /64 that I need, etc..

                        I would take a guess that your paying more than $45 a year for this single server??  So for these 3 vps that cost me all of $45 a year I have 3 different /64s – I can see no freaking reason why they want to give you only a /112..  Now agreed that is more than enough IPs for anyone..  But that is not the point - ipv6 is /64 or you break shit!!!  And while yes coming from a ipv4 mindset it seems to be beyond wasteful.. I too when first starting out with ipv6 was like wtf... That is a lot of IPs for every l2 network your going to have..  And it does seem crazy..  But its just nuts how big the space really is..

                        They should of gotten /32.. if not multiples of them.. With a /32 your talking 16 Million /56's do they possible have 16 million customers in this DC?  For /64s your talking 4G.. With that many networks available why would you want/need or desire to break shit when going against the rfcs..

                        For gosh sake they could go and get a /48 from HE and bring it into their DC and they would have 64K /64's to hand out to their users.. That they are breaking shit up into /112 makes NO sense no matter how you look at it..

                        ipv6assignedspace.jpg
                        ipv6assignedspace.jpg_thumb

                        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

                          Yeah, and even then, a shared /64 makes less sense than a dedicated /64 per host.

                          But that is not the point - ipv6 is /64 or you break shit!!!

                          Yep, that's why I said a shared /64, if they won't give a unique /64.  Either will work fine, but a /112 won't.

                          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

                            Because that /112 (which isn't a real /112, it's a shared /64 where i'm simply only allowed to use /112 without it being an actual subnet) is the dynamic standard for single-server-single-link in their provisioning system,

                            That makes more sense.  They give you a 65K block of addresses and you're supposed to do a static config or possibly mapped DHCP for your systems.  That means there could be 2^48 other systems in there sharing that /64.  ;)

                            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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