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    Use of both dhcp and slaac, advanced configuration

    Scheduled Pinned Locked Moved IPv6
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    • crc_error_79C
      crc_error_79 @Bob.Dig
      last edited by

      @Bob-Dig
      Thanks I will read something about (because the only thing I know about is that it is a sort of nat)

      Bob.DigB 1 Reply Last reply Reply Quote 0
      • Bob.DigB
        Bob.Dig LAYER 8 @crc_error_79
        last edited by

        @crc_error_79 said in Use of both dhcp and slaac, advanced configuration:

        (because the only thing I know about is that it is a sort of nat)

        It doesn't has the problem of being only one address everything has to be NATed to but maybe don't start your IPv6 journey with that. 😱

        1 Reply Last reply Reply Quote 0
        • JKnottJ
          JKnott @crc_error_79
          last edited by

          @crc_error_79 said in Use of both dhcp and slaac, advanced configuration:

          I used your guide and it worked to, but in that way (with my skills) I can't easy manage the devices connected to the network since with slaac all devices get only the prefix and not the entire address.

          What is it you're trying to manage? When you use the consistent address for DNS, you will always be able to reach it, no matter what the privacy addresses are.

          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...

          crc_error_79C 1 Reply Last reply Reply Quote 0
          • crc_error_79C
            crc_error_79 @JKnott
            last edited by

            @JKnott
            you are right but how can I set an host override on the dns resolver if I don't know the ipv6 address?
            I must go around the house and check every devices.. If I use dhcpv6 all is "centralized" since the router knows every ip it leases
            Or am I wrong? 🙄

            JKnottJ 1 Reply Last reply Reply Quote 0
            • JKnottJ
              JKnott @crc_error_79
              last edited by

              @crc_error_79

              You don't set a host override. You just use the address as is. I mentioned I had to determine the consistent address recently for a new tablet. The way I did that was set up Packet Capture to capture the tablet MAC address and only IPv6. Then whatever address turned up when I used a browser to access the Internet was not the persistent address. Since there was only 2 address displayed in the settings, I had a good idea which one was persistent. You can easily grab the MAC address when you convert an IPv4 DHCP address, found in the DHCP log, to host override.

              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...

              JKnottJ crc_error_79C 2 Replies Last reply Reply Quote 0
              • JKnottJ
                JKnott @JKnott
                last edited by

                @crc_error_79

                Here's another way to determine the persistent address. This is on Linux, using the ip -6 address show command.

                inet6 fd48:1a37:2160:0:90b4:60da:a900:2997/64 scope global temporary dynamic
                inet6 fd48:1a37:2160:0:d37b:1ca2:4d85:a38d/64 scope global temporary deprecated dynamic
                inet6 fd48:1a37:2160:0:76d4:35ff:fe5b:f5fa/64 scope global dynamic mngtmpaddr

                I used grep to display only my ULA addresses. You can tell by reading the text which is the persistent address. It's the last one. Similar can be done with the ifconfig command on Linux and FreeBSD or ipconfig on Windows.

                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...

                1 Reply Last reply Reply Quote 0
                • crc_error_79C
                  crc_error_79 @JKnott
                  last edited by

                  @JKnott

                  It is a valid option, but to me is more complicated than what I used..
                  Since it requires packet capture (I know what it is but I don't know how to use it) or the physical access.
                  As said many times maybe it is because I am comfortable with dhcp and ipv4.

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

                    @crc_error_79

                    It's no more complicated than setting up a DHCPv6 server. Also, packet capture is a very useful tool for solving problems. I frequently use either Packet Capture or Wireshark.

                    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...

                    crc_error_79C 1 Reply Last reply Reply Quote 0
                    • crc_error_79C
                      crc_error_79 @JKnott
                      last edited by

                      @JKnott
                      I will take a look about it.

                      This morning I had a strange problem I never had with the ipv4.
                      The state table size was completely filled (198000 rows), cpu at 100% (proxmox i7 7700 with 4 cores assigned) and internet down.
                      What could be the cause? What do you think?

                      Firewall rules are the same for both ipv4 and ipv6, only block inter-vlan traffic and allow anyware (unless pfBlocker says no) on internet

                      JKnottJ 1 Reply Last reply Reply Quote 0
                      • JKnottJ
                        JKnott @crc_error_79
                        last edited by

                        @crc_error_79

                        I have no idea what would cause 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...

                        crc_error_79C 1 Reply Last reply Reply Quote 0
                        • crc_error_79C
                          crc_error_79 @JKnott
                          last edited by

                          @JKnott
                          I am not in front of the pfsense (because I am at work now) but could it be the virtual ip or something related to the internal lan that tries to access to internet?

                          JKnottJ 1 Reply Last reply Reply Quote 0
                          • JKnottJ
                            JKnott @crc_error_79
                            last edited by

                            @crc_error_79

                            I don't think so. I have a virtual IP as described in my ULA article and it's used all the time. However, I am not using pfBlocker.

                            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...

                            crc_error_79C 1 Reply Last reply Reply Quote 0
                            • crc_error_79C
                              crc_error_79 @JKnott
                              last edited by

                              @JKnott
                              I will check tomorrow, after the reboot I did the issue has gone. Maybe it was caused by the temporary nic I am using (an usb 2.5 gb) for the wan

                              Thanks again ;)

                              1 Reply Last reply Reply Quote 0
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