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    Local ISP weird behaviour w/ IPv6 via DHCP6

    Scheduled Pinned Locked Moved IPv6
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    • Y
      YoLo88 @Gertjan
      last edited by

      @Gertjan said in Local ISP weird behaviour w/ IPv6 via DHCP6:

      You didn't show the log lines where it eventually got eventually a valid DHCP6 lease ?

      Thank you very much for your response!!

      Those were the first set of logs @17:26. It only get's a valid IPv6 lease if I disconnect/reconnect the WAN interface via the WebUI. And it reliably does get an IPv6 address every time I do this. and then.... 10 minutes later it drops and never recovers.

      This must be a setting somewhere to replicate how the Fritz box was getting IPv6 because that would ... just ... work.

      1 Reply Last reply Reply Quote 0
      • Y
        YoLo88
        last edited by

        @YoLo88 said in Local ISP weird behaviour w/ IPv6 via DHCP6:

        send renew to ff02::1:2%pppoe0

        Is the problem this PPPoE IPv6 address - "ff02::1:2%pppoe0"

        Jul 18 09:57:49	dhcp6c	86580	Sending Solicit
        Jul 18 09:57:49	dhcp6c	86580	set client ID (len 14)
        Jul 18 09:57:49	dhcp6c	86580	set identity association
        Jul 18 09:57:49	dhcp6c	86580	set elapsed time (len 2)
        Jul 18 09:57:49	dhcp6c	86580	set option request (len 4)
        Jul 18 09:57:49	dhcp6c	86580	set IA_PD prefix
        Jul 18 09:57:49	dhcp6c	86580	set IA_PD
        Jul 18 09:57:49	dhcp6c	86580	send solicit to ff02::1:2%pppoe0
        Jul 18 09:57:49	dhcp6c	86580	reset a timer on pppoe0, state=SOLICIT, timeo=1135, retrans=108036
        

        Where the hell does that come from? I can't ping it and it doesn't look like it relates to either the fe80 link local addressing or real IPv6 addressing that I'm getting from my ISP...

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        • Y
          YoLo88
          last edited by

          Ahh, FF02::1 is Link-local multicast address All nodes (broadcast)

          GertjanG 1 Reply Last reply Reply Quote 0
          • GertjanG
            Gertjan @YoLo88
            last edited by

            @YoLo88

            As this is IPV6 and IPv4 over PPPoE, did you set a MTU value less then 1500 ?

            This one :

            @YoLo88 said in Local ISP weird behaviour w/ IPv6 via DHCP6:

            Jul 16 17:36:41 rc.gateway_alarm 99403 >>> Gateway alarm: WAN_DHCP6 (Addr:[fe80::xxx:xxxx:xxxx:xxxx]%pppoe0 Alarm:1 RTT:1.447ms RTTsd:.421ms Loss:21%)

            is strange.
            When the 10 minute DHCP6 lease is over, the IP6 info is still valid. Lease renewal starts to happen half way the lease duration. That is, DHCP4 works like that. When a device receives a DHCP4 lease valid for 6 hours, renewal start at 3 hours.
            If that is the same for IPv6, then why ..... there is a gateway alarm = ping6 doesn't pass anymore.
            I'm pretty sure that has nothing to do with the DHCP6 lease renewal.
            Was the pppoe interface already reset before that gateway alarm line .
            The pppoe connection itself went bad ? The pppoe renewal is a slow process. And while that's in progress, the IPv6 that goes over it can't be created.

            Does the IPv4 use the same pppoe connection ? IPv4 doesn't complain / stays in a working condition ?

            I'm just brainstorming here. It's years now my ISP left pppoe for what is was : perfect for the waste bin.

            No "help me" PM's please. Use the forum, the community will thank you.
            Edit : and where are the logs ??

            Y 1 Reply Last reply Reply Quote 0
            • Y
              YoLo88 @Gertjan
              last edited by

              @Gertjan Thanks again for your input. Much appreciated.

              The MTU appears to set itself to 1492

              I tried disabling gateway monitoring but it didn't make any difference.

              IPv4 and IPv6 are sharing the same PPPoE connection yes, I have the "Use IPv4 connectivity as parent interface" - "Request a IPv6 prefix/information through the IPv4 connectivity link" option ticked and yes IPv4 is fine. It renews without a problem.

              My ISP is garbage for tech support. I can't get anyone even remotely technical to speak to me. They just tell me to put the Fritz box back on there or it's my problem to figure out which is kind of fair enough. This IPv6 connection is stable on Fritzbox but not on PFSense. Therefore, it must be a setting in PFSense that I can tweak to fix the stability.

              Y 1 Reply Last reply Reply Quote 0
              • Y
                YoLo88 @YoLo88
                last edited by

                What about https://redmine.pfsense.org/issues/13237 ? Some notes in there about strange behaviour that happens repeatedly unless the firewall is physically rebooted? Going to give it a cold boot now and see how that goes...

                Y 1 Reply Last reply Reply Quote 0
                • Y
                  YoLo88 @YoLo88
                  last edited by YoLo88

                  Aaaaaaand 13 minutes of uptime and IPv6 is still stable!

                  alt text

                  Y 1 Reply Last reply Reply Quote 0
                  • Y
                    YoLo88 @YoLo88
                    last edited by

                    And it lasted about 50 minutes before it died and didn't recover again. So, better but still not great.

                    GertjanG 1 Reply Last reply Reply Quote 0
                    • GertjanG
                      Gertjan @YoLo88
                      last edited by

                      @YoLo88

                      So it did renew 4 times at least, and failed to do so the 5th time ?

                      No "help me" PM's please. Use the forum, the community will thank you.
                      Edit : and where are the logs ??

                      1 Reply Last reply Reply Quote 0
                      • Y
                        YoLo88
                        last edited by

                        Looks like I was lacking "rapid commit" under advanced IP options. I tried to post instructions here but it keeps getting flagged as Spam. Check out https://www.reddit.com/r/PFSENSE/comments/1duuc6o/ipv6_troubles_unstable_pppoe_ipv6_address_via/ for the full post.

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