Netgate Discussion Forum
    • Categories
    • Recent
    • Tags
    • Popular
    • Users
    • Search
    • Register
    • Login

    Use of both dhcp and slaac, advanced configuration

    Scheduled Pinned Locked Moved IPv6
    48 Posts 4 Posters 15.0k Views
    Loading More Posts
    • Oldest to Newest
    • Newest to Oldest
    • Most Votes
    Reply
    • Reply as topic
    Log in to reply
    This topic has been deleted. Only users with topic management privileges can see it.
    • Bob.DigB
      Bob.Dig LAYER 8 @crc_error_79
      last edited by Bob.Dig

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

      what do you mean?

      This, kinda:

      The only thing I have to do is to change the virtual IP prefix as well as the slaac with the new one

      crc_error_79C 1 Reply Last reply Reply Quote 0
      • crc_error_79C
        crc_error_79 @Bob.Dig
        last edited by

        @Bob-Dig
        ah ok..
        to me it is not a big deal, better change 2 parameters than at least 20 dhcpv6 static assigments..
        Also I think that in this way I could have a public network and private one, I don't know if for security it is better..

        but as I said before maybe am I still too ipv4 focused

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

          @crc_error_79 You could do it the other way around, use track interface for GUA and ULA in RA.
          Or try NPt.

          crc_error_79C 1 Reply Last reply Reply Quote 0
          • crc_error_79C
            crc_error_79 @Bob.Dig
            last edited by

            @Bob-Dig
            I can't use track interface because my isp assigns to the wan a local link.. Also I don't want to use nat..

            I think that this way or the one @JKnott suggested are the better, but maybe I am wrong (am an home user not an network engineer 😁 )

            My goal is to have a single point where to control all the devices connected to the lan so I can set to each device a name and network information.
            I can do it with dhcp (+dns) but not with slaac (or at least I think, I need some examples or try it)

            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:

              I can't use track interface because my isp assigns to the wan a local link..

              Does this defeat track interface?

              crc_error_79C 1 Reply Last reply Reply Quote 0
              • crc_error_79C
                crc_error_79 @Bob.Dig
                last edited by

                @Bob-Dig
                I don't know, as said am not an expert..

                but if I set track interface on the lan the only option is WAN and it has a local link, not routable.. see? I am using pppoe for the ipv4 connection

                fd203c04-de7d-4384-aa77-8206e88a37e8-image.png

                4fda769f-4270-467b-9ddb-18572fd4ecb6-image.png

                Bob.DigB JKnottJ 2 Replies Last reply Reply Quote 0
                • Bob.DigB
                  Bob.Dig LAYER 8 @crc_error_79
                  last edited by Bob.Dig

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

                  but if I set track interface on the lan the only option is WAN and it has a local link, not routable.. see? I am using pppoe for the ipv4 connection

                  Just try it, ping an IPv6 address from an interface which "tracks". Do a reboot to be sure.

                  crc_error_79C 1 Reply Last reply Reply Quote 0
                  • crc_error_79C
                    crc_error_79 @Bob.Dig
                    last edited by

                    @Bob-Dig
                    Ok but I need a IPv6 Prefix ID, I never use track interface, where I can get it?

                    Bob.DigB JKnottJ 2 Replies Last reply Reply Quote 0
                    • Bob.DigB
                      Bob.Dig LAYER 8 @crc_error_79
                      last edited by

                      @crc_error_79 Just use 0 on your first LAN. But on WAN you have to put in the delegation size to you. If you are uncertain, use 60.

                      crc_error_79C JKnottJ 2 Replies Last reply Reply Quote 0
                      • crc_error_79C
                        crc_error_79 @Bob.Dig
                        last edited by

                        @Bob-Dig
                        I tried but it is not work because (I think) the slaac can't autoassign an ipv6 if the gateway is a local link

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

                          @crc_error_79

                          You seem to be creating your own problems. Use SLAAC to get the prefix for each interface for global addresses. Use my instructions for ULA and forget about DHCPv6, you don't need it.

                          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
                          • JKnottJ
                            JKnott @crc_error_79
                            last edited by

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

                            but if I set track interface on the lan the only option is WAN and it has a local link, not routable.. see? I am using pppoe for the ipv4 connection

                            Use SLAAC. Why are you worrying about the link local address? That's entirely normal. With IPv6, the link local address is frequently used for routing. That link local address is used only for reaching the next hop and has nothing to do with whatever addresses you are assigned.

                            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
                            • JKnottJ
                              JKnott @crc_error_79
                              last edited by

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

                              Ok but I need a IPv6 Prefix ID, I never use track interface, where I can get it?

                              With DHCPv6-PD, your prefix is assigned to you.

                              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
                              • JKnottJ
                                JKnott @Bob.Dig
                                last edited by

                                @Bob-Dig said in Use of both dhcp and slaac, advanced configuration:

                                Just use 0 on your first LAN. But on WAN you have to put in the delegation size to you. If you are uncertain, use 60.

                                I believe he said he gets a /56, so that's what he would use.

                                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
                                • JKnottJ
                                  JKnott @crc_error_79
                                  last edited by

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

                                  I tried but it is not work because (I think) the slaac can't autoassign an ipv6 if the gateway is a local link

                                  Where are you getting this nonsense from?

                                  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 crc_error_79

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

                                    @crc_error_79

                                    You seem to be creating your own problems. Use SLAAC to get the prefix for each interface for global addresses. Use my instructions for ULA and forget about DHCPv6, you don't need it.

                                    On my post 16 my problems were solved, that was exactly my goal, then I asked if there were a better or more security / efficient etc way to do it.

                                    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.
                                    So on router side if I don't know which ip has a device how can I manage it (firewall rules etc)

                                    I think that with slaac I can't do a thing like this below. I have to use dns with the hope that the address doesn't change.

                                    b5d08d40-3054-446d-a8a8-f15d328a133f-image.png

                                    Also if the prefix changes (for any reason) how can I be sure that the remaining part will stay the same?

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

                                    With DHCPv6-PD, your prefix is assigned to you.

                                    To configure the wan, I followed this guide from my isp link, ok it is in Italian but you can look at the pictures, they said to use "static ipv6", add the given /56 + the remain part to create the network and the gateway, and that is what I initially did.

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

                                    I believe he said he gets a /56, so that's what he would use.

                                    yes I get a /56

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

                                    Where are you getting this nonsense from?

                                    If I set "track interface" -> WAN instead of "static" but that interface has a local link it don't work, at least to me.

                                    [edit] correct the post link (16, not 15)

                                    Bob.DigB JKnottJ 2 Replies Last reply Reply Quote 0
                                    • crc_error_79C crc_error_79 referenced this topic on
                                    • Bob.DigB
                                      Bob.Dig LAYER 8 @crc_error_79
                                      last edited by Bob.Dig

                                      @crc_error_79 It looks like you get a static prefix, that is great, so forget "track interface".

                                      Also you can use the DHCPv6 Server for static mappings, it is almost the same as with IPv4.

                                      If you really think that you will switch ISPs in the near future, use NPt. It is not regular NAT and will work just fine with ULAs, as long as you have (only) one ISP.

                                      crc_error_79C 1 Reply Last reply Reply Quote 1
                                      • 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
                                            • First post
                                              Last post
                                            Copyright 2025 Rubicon Communications LLC (Netgate). All rights reserved.