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    No LAN IPv6 address with Track Interface on WAN

    Scheduled Pinned Locked Moved IPv6
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    • JKnottJ Offline
      JKnott @azaclauson
      last edited by

      @azaclauson
      Having the modem in bridge mode allows pfSense to work with what's behind it. To use IPv6, the ISP normally uses DHCPv6-PD, which provides the prefix that pfSense assigns to the LANs. You may also have an IPv6 WAN address, which has absolutely nothing to do with the LAN prefixes, or routing for that matter.

      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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      • A Offline
        azaclauson
        last edited by

        To use IPv6, the ISP normally uses DHCPv6-PD

        Yes but as best I can tell that's my exact problem. My ISP is not providing Prefix Delegation. Instead a single /64 network is available on the modem.

        I have been relatively successful switching pfSense from operating as a router between the WAN and LAN interfaces to instead operating as a transparent bridge. I've now got usable DHCP IPv6 addresses on my Windows and Linux machines and I can set firewall rules. I think there's still something missing with Router Advertisements but I can play around with that further. For the moment I know have a local firewalled IPv6 network.

        JKnottJ 1 Reply Last reply Reply Quote 0
        • JKnottJ Offline
          JKnott @azaclauson
          last edited by

          @azaclauson said in No LAN IPv6 address with Track Interface on WAN:

          Yes but as best I can tell that's my exact problem. My ISP is not providing Prefix Delegation. Instead a single /64 network is available on the modem.

          How can you tell that, when you're not set up to use prefix delegation? You will not see it coming from a modem in gateway mode, ever. You will see it only in bridge mode. All you'll see in gateway mode is router advertisements containing the prefix for the connected LAN.

          I posted a full DHCPv6 sequence earlier, which shows the PD part. Do you see anything like that coming from your modem? If not, you don't have it. If you want to have more than 1 /64, you must use bridge mode. There is no way around that.

          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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          • J Offline
            Jim Coogan
            last edited by

            Hi very new to IPv6 but I am in exact same scenario. Modem is in gateway mode and cannot but put into bridge.

            Modem's IPv6 is /64 and plugged into WAN on pfsense and pfsense gets an IPv6 ip on WAN.

            What I am a little confused about is what DHCPv6 Relay is for? Was thinking I could relay the DHCPv6 IPs my modem is handing out to my LAN but apparently not as I'm not seeing that suggested. I'm guessing if the LAN did pick up these relayed addresses that would be a routing problem I'm not quite grasping?

            Thanks

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            • JKnottJ Offline
              JKnott @Jim Coogan
              last edited by

              @Jim-Coogan

              As on IPv4, the relay simply means your DHCP server is elsewhere, instead of on the local network. It forwards the DHCP requests to that remote server.

              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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              • J Offline
                Jim Coogan
                last edited by

                Thanks @JKnott
                So I was thinking thats why this would be viable in this scenario where WAN which sees DHCPv6 server (my non bridged modem) and could theoretically relay and hand out address on my lan. I guess though there would be routing problems without a lot of static routes. ie gateway modem wouldn't know how to route to the IPV6 LAN clients through pfsesne unless it could take static routes (and mine cant) and pfsense would think any traffic it gets on LAN for the locally assigned IPv6 addresses should go out WAN without static routes as well.

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                • A Offline
                  azaclauson
                  last edited by

                  @Jim-Coogan what ended up being a show stopper for me was my ISP only allocating a /64 range to my modem. For DHCPv6 relay to work with pfSense acting as a router you need to be able to use DHCPv6 with Prefix Delegation. To do that you need a bigger allocation than /64, e.g. /56 or /60 etc.

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