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    SLAAC & Dynamic prefix

    Scheduled Pinned Locked Moved IPv6
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    • Y
      YannTKO
      last edited by YannTKO

      Hi,
      My ISP gives me a dynamic prefix and it is well managed by the DHCPv6 server (the prefix is correctly detected).I also use SLAAC (RA assisted mode) to provide IPs for other devices.

      My question is:
      When my prefix change, I always have to enter it manually (copy/paste from DHCPv6 server) in the RA Subnet(s) to get routable IPs. Is there a workaround to avoid this and to do it automatically ?

      At the beginning, I wanted to use only SLAAC but due to the dynamic prefix, I have been forced to use the DHCPv6 server.

      Thank you.

      JKnottJ S 2 Replies Last reply Reply Quote 0
      • JKnottJ
        JKnott @YannTKO
        last edited by

        @YannTKO

        You can use Unique Local Addresses for your local network. However, first check to see if System / Advanced / Networking / Do not allow PD/Address release has been selected. If it isn't, your prefix will change.

        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...

        Y 2 Replies Last reply Reply Quote 2
        • Y
          YannTKO @JKnott
          last edited by YannTKO

          @JKnott
          It's working fine with ULA but I had to setup NPTv6 with the delegated prefix of my interface (automatically detected and preset).
          I also disabled the DHCPv6 and set the RA in unmanaged mode to have the initial setup I wanted.
          I reset my WAN manually for checking and everything is working perfectly.
          Thank you.

          1 Reply Last reply Reply Quote 0
          • Y
            YannTKO @JKnott
            last edited by

            This post is deleted!
            1 Reply Last reply Reply Quote 0
            • S
              SteveITS Galactic Empire @YannTKO
              last edited by

              @YannTKO are you asking about

              RA Subnet(s)
              Subnets are specified in CIDR format. Select the CIDR mask that pertains to each entry. If no subnets are specified here, the RA Daemon will advertise to the subnet to which the router's interface is assigned

              If so note the bolded part and leave it blank.

              Pre-2.7.2/23.09: Only install packages for your version, or risk breaking it. Select your branch in System/Update/Update Settings.
              When upgrading, allow 10-15 minutes to restart, or more depending on packages and device speed.
              Upvote 👍 helpful posts!

              Y 1 Reply Last reply Reply Quote 0
              • Y
                YannTKO @SteveITS
                last edited by YannTKO

                @SteveITS
                If I leave it blank, my devices don't get IPs. I followed the @JKnott procedure and now it's running well.

                1 Reply Last reply Reply Quote 0
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