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    OpenVPN DHCPv6 log flood

    Scheduled Pinned Locked Moved IPv6
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    • A
      asterix
      last edited by

      @doktornotor:

      Perhaps you need to add the UnicastOnly flag?  ;D

      ducks and covers

      Lol would had done so if there was an option for it.. hehe ;D

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      • D
        doktornotor Banned
        last edited by

        :D :D :D

        So, does it work when you edit /var/etc/radvd.conf and restart radvd service? If not, you might try with TAP instead of TUN.

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        • A
          asterix
          last edited by

          Yup tried that already. Didn't work. It removes the flag on service restart.

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          • D
            doktornotor Banned
            last edited by

            1/ Stop the service.
            2/ Edit the config.¨
            3/ Run  /usr/local/sbin/radvd -p /var/run/radvd.pid -C /var/etc/radvd.conf -m syslog

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            • A
              asterix
              last edited by

              That didn't work either. It still removes the flag on service restart.

              Also, where are all the system log files stored? Do they get deleted after a certain period of time? I don't want my hard disk filled up with these logs.

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              • D
                doktornotor Banned
                last edited by

                Yes of course it removed the flag when you go messing with the GUI! The whole purpose of the above was to test whether it actually does fix your issue.

                (The logs are circular, fixed size.)

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                • A
                  asterix
                  last edited by

                  @doktornotor:

                  Yes of course it removed the flag when you go messing with the GUI! The whole purpose of the above was to test whether it actually does fix your issue.

                  (The logs are circular, fixed size.)

                  Issue still persists and adding the flag did not fix it.

                  Logs are fixed size.. yes, but the number of logs keeps increasing.

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                  • D
                    doktornotor Banned
                    last edited by

                    How does the number of logs keep increasing?  :o ???

                    (If the flag does not help, move to TAP.)

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                    • A
                      asterix
                      last edited by

                      changing OpenVPN to tap stops the flood but I need to use tun for the VPN clients.

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                      • D
                        doktornotor Banned
                        last edited by

                        Well… it stops the flood because tap supports broadcast. Not really sure how's this fixable beyond muting the log. You normally do not run DHCP{,v6}/RA through tun tunnels. Why are you assigning the interface at all?

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                        • K
                          kejianshi
                          last edited by

                          There should probably be Router advertisements on but not DHCP/v6

                          I'm assuming trying to tunnel IPv6 over a IPV4 vpn?

                          Mine works this way.

                          You need no DHCP
                          You do need router advertisements to your /48 (I assume)
                          And your IPV6 openvpn interface as the DNS server entered in DNS server list in Router advertisements.

                          You will also need to push a route in openvpn.

                          push "route-ipv6 2000::/3";
                          keepalive 5 120;

                          Anyway - It works for me.  My remote clients all get a public IPV6 address and browsing IPV6 sites works fine

                          P.S.  I'm using TUN

                          But yeah, the "do you need to add the UnicastOnly flag?" is one of a many BS log clutter I ignore.  Mine also does that.

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                          • A
                            asterix
                            last edited by

                            You have described my exact configuration. I have IPv6 tunnel over IPv4 and using it for VPN. Have RA on and DHCP/v6 off as the IPs are handed out by OpenVPN.

                            Yes, I need RA as IPv6 address is not handed out without it since in /48 (/64 subnet but from a /48 as I have multiple subnets from the /48 making it /64). The DNS resolver works great with IPv6 without any config changes. I presume it pickups the subnet's gateway and uses it to resolve all IPv6 queries.

                            Surprisingly I do not need to push route in OpenVPN, seems RA takes care of that.

                            So using TUN I may have to ignore the log flood till there is a fix OR till my ISP starts using IPv6.

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                            • K
                              kejianshi
                              last edited by

                              I'm ignoring it…

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