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    Unable to get DHCPv6 to work

    Scheduled Pinned Locked Moved IPv6
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    • P
      pst @zingbats
      last edited by

      @zingbats Odd, neither of the new logs contains the Prefix Delegation element in the request. I wonder if the interface needs a restart before the configuration is applied? Try restart the WAN in Status / Interfaces and check if that makes a difference.

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        zingbats @pst
        last edited by zingbats

        @pst I did a full reboot with just the prefix hint box. Log attached.

        I am also going to back up and do a factory reset to see if that works.
        EDIT: Factory reset did nothing.

        pfsense prefix hint after reboot.pcapng

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          pst @zingbats
          last edited by

          @zingbats nope, still the same.

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            zingbats @pst
            last edited by

            @pst Well the factory reset didn't help either. Any other ideas?

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              pst @zingbats
              last edited by pst

              @zingbats As you suggested, you could try the MAC spoofing. If that fixes the VF rejection, great but it still doesn't explain why pfSense doesn't include the Prefix Delegation hint when it has been configured to do so. Which version of pfSense are you running?

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                zingbats @pst
                last edited by

                @pst when I did the factory reset I spoofed the mac in the wizard and it changed nothing.

                Running latest pfSense CE (2.7.2), x86

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                  pst @zingbats
                  last edited by

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                    pst @zingbats
                    last edited by

                    @zingbats I'm out of ides for the moment. I need to pop out for a few hour, hopefully I have some new ideas when I get back.

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                      pst @zingbats
                      last edited by pst

                      @zingbats I am trying to understand how VF is configuring the IPv6 connection, postings on the net suggests they are in the process of rolling out native IPv6 support. Could you post the result of https://ipv6-test.com/ using the ISP router? It should indicate if you have native IPv6, or 6to4 (see https://forum.vodafone.co.uk/t5/Other-broadband-queries/ipv6-settings/td-p/2742474/page/2)

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                      • Z
                        zingbats @pst
                        last edited by

                        @pst I had already read up on the 6to4, but as I'm a new customer, I knew I'd be on the native. Here's the screenshot from the vodafone router

                        Vodafone ipv6.png

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                          pst @zingbats
                          last edited by

                          @zingbats good you've native, pity as it closes another avenue. With everything you've already tested it doesn't really leave much else to try. I still suspect VF is rejecting the DHCPv6 Request because pfSense is not sending the same parameters as the original router.

                          Here's what pfSense is sending

                          c4e7587d-6dd1-4d84-aa29-dff393df9127-image.png

                          Whereas the VF router sends additional information:

                          597183f2-4db4-4205-8c2d-5309169b6c61-image.png
                          2368d8cd-1153-4431-b384-147e6d160291-image.png

                          You could try adding the missing parameters (Option Request rDNS, Reconfigure Accept, Domain Name, and Prefix Delegation (which should have been included when setting Send Hint)) by enabling WAN / DHCP6 Client Configuration / Advanced Configuration, and then populate Advanced DHCP6 Client Configuration. I have never attemped this, and would not have much to contribute. There might be someone else though, that can provide the final pieces of this puzzle.

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                            zingbats @pst
                            last edited by

                            @pst I tried the advance options, but it seems like the manual that pfSense references does not support these DHCP6 options.

                            https://man.freebsd.org/cgi/man.cgi?query=dhcp6c.conf&apropos=0&sektion=0&manpath=FreeBSD+10.3-RELEASE+and+Ports&arch=default&format=html

                            I imagine that means it's game over sadly.

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                              pst @zingbats
                              last edited by

                              @zingbats said in Unable to get DHCPv6 to work:

                              I imagine that means it's game over sadly.

                              Not yet, it might just be a little more complicated than first imagined :)

                              Let's try and add one parameter:

                              e94d63c7-c781-472e-b8e0-80525ac3f4cd-image.png

                              I think this falls under the manual section

                              b39f786d-7899-4cb7-9fa8-9368c9b94564-image.png

                              In pfSense that would I guess translate into

                              b1e497bb-368b-42ba-a5df-4eb101c4384a-image.png

                              If that works we should see pfSense sending this parameter to the DHCP6 Request, and we can continue with the next parameter.

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                              • Z
                                zingbats @pst
                                last edited by

                                @pst I have tried setting JUST this as requested, and replicating the complete default config file (which includes domain-name-servers) and I don't see any options passed in the packets.

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                                  pst @zingbats
                                  last edited by

                                  @zingbats I wonder if there's a bug in the 2.7.2 version of pfSense then. I did a test on my 23.09.1, adding sip-server-list as advanced configuration. I noticed that ONLY sip-server-list was requested, not DNS servers and other stuff which is usually asked for. The DHCPv6 Request was rejected and no IPv6 connectivity established. That seems to indicate that the Advanced DHCP6 configuration needs to be a complete configuration, AND that the DHCPv6 server might reject a Request that does not include everything it is expecting.

                                  That both the Advanced DHCP6 configuration and "Send IPv6 prefix hint" seems to be ignored by pfSense 2.7.2, suggests a bug IMHO.

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                                  • Z
                                    zingbats @pst
                                    last edited by

                                    @pst luckily I'm in my 14 day cancellation window with my ISP so I'm moving to BT who seem to better support IPv6 without the need for non-standard options. Hopefully IPv6 will become more stable and configurable in pfsense soon, as it seems the dhcp6c is missing modern request options such as those required by vodafone.

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                                      pst @zingbats
                                      last edited by

                                      @zingbats said in Unable to get DHCPv6 to work:

                                      request options such as those required by vodafone

                                      or it could just be us not understanding what is needed...

                                      BTW, have you tried configuring SLAAC instead of DHCP6 on the WAN? (the last straw)

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                                      • Z
                                        zingbats @pst
                                        last edited by

                                        @pst SLAAC yielded no luck, unfortunately.

                                        I did another clean install of pfsense and couldn't get the options to appear in the DHCP6 packets. As part of my research, I decided to test OPNSense. You can see in my packet below that it sent one (spoofing the MAC of the vodafone router) but it didn't seem to send it directly to the Nokia media convertor / modem. I think I'm right in assuming it broadcast it? Don't forget these devices are on their own VLAN to allow packet sniffing. Is that relevant here?

                                        I am not asking for help with OPNSense because I much prefer supporting pfsense, but I wonder if this knowledge might help us? i.e. what is OPNSense using as a DHCP6 Client, and why is it sending the packet differently.

                                        OPNSense DHCP6.pcapng

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                                        • M
                                          mikemod @zingbats
                                          last edited by mikemod

                                          @zingbats I had similar issues when trying to get my BT IPv6 working, these are the settings I changed to get it to work in the end.
                                          I think I had to reset the connection once the changes had been made.

                                          In the WAN settings set to DHCP6 and in client config

                                          6.jpg

                                          1.jpg

                                          In the LAN settings page set track interface and under Track IPv6 Interface

                                          2.jpg

                                          3.jpg

                                          And then in the Firewall LAN rules make sure you have IPv6 added to the any rule.

                                          5.jpg

                                          4.jpg

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                                            zingbats @mikemod
                                            last edited by

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