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    FYI: Ipv6 users should use 2.pool.ntp.org as their NTP server

    IPv6
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    • IsaacFLI
      IsaacFL
      last edited by

      For those who have ipv6 and want to use pool.ntp.org as the time server for your NTP clients, they should use 2.pool.ntp.org as this is the only one that returns both A and AAAA records for NTP servers. pool.ntp.org is ipv4 only and many people by default use pool.ntp.org

      This also works for regional servers. i.e I am in the US so I use 2.us.pool.ntp.org. It also works for the distro specific entries like 2.pfsense.pool.ntp.org and 2.fedora.pool.ntp.org. Only 2 returns v6 entries.

      Sergei_ShablovskyS 1 Reply Last reply Reply Quote 3
      • Sergei_ShablovskyS
        Sergei_Shablovsky @IsaacFL
        last edited by

        @isaacfl What is situation on Apr 2023 with this?

        I mean is there are new NTP pools with AAAA added, or old reconfigured ?

        And another question how You check ability of servers/pools to correctly working with ipv6 clients?

        Thanks!

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        johnpozJ 1 Reply Last reply Reply Quote 0
        • johnpozJ
          johnpoz LAYER 8 Global Moderator @Sergei_Shablovsky
          last edited by johnpoz

          @sergei_shablovsky I think 2.xxxx the only pools that have AAAA entries..

          Be it country, or zone based like north-america or africa, asia, etc.. Or vendor specific like 2.pfsense.ntp

          NTP suggests that if your a vendor that will be setting up ntp on the devices you sell/distribute that you register your own vendor name for the zones, etc. Lets say it is stronger than a suggestion ;)

          "You must absolutely not use the default pool.ntp.org zone names as the default configuration in your application or appliance. "

          Now what a user changes ntp to use after they set it up, would not be the vendors problem - but ntp is pretty against vendors shipping their stuff with the default pool names..

          https://www.ntppool.org/en/vendors.html

          But I believe only ones that start with 2 have IPv6, all the other 0, 1 and 3 only have IPv4

          An intelligent man is sometimes forced to be drunk to spend time with his fools
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          1 Reply Last reply Reply Quote 1
          • maverickwsM
            maverickws
            last edited by

            I use time.apple.com and time.euro.apple.com both pools and IPv6 enabled for idk maybe over a decade?

            D 1 Reply Last reply Reply Quote 0
            • compuguyC
              compuguy
              last edited by

              You can add time.nist.gov as a ntp host/pool that returns a AAAA record to the list as well.

              RobbieTTR 1 Reply Last reply Reply Quote 2
              • RobbieTTR
                RobbieTT @compuguy
                last edited by

                The 'teaching' back in the day was to use real v4 or v6 addresses as part of the mix to ensure that a DNS failure would not interrupt NTP.

                The NTP pools discouraged that these days but old habits and logic die hard.

                ☕️

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

                  I use 3 stratum 1 servers from a local Internet exchange, along with 2 stratum 2 from the Canadian government and time.google.com. The 3 Internet exchange servers and Google have both IPv4 and IPv6 addresses available.

                  The University of Toronto has two NTP servers, tick & tock. 😉

                  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...

                  RobbieTTR 1 Reply Last reply Reply Quote 0
                  • RobbieTTR
                    RobbieTT @JKnott
                    last edited by RobbieTT

                    @jknott

                    I like to have a stratum 1 on the LAN side, as part of the wider mix:

                     2023-05-02 at 15.26.45.png

                    ☕️

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

                      @robbiett

                      Unfortunately, many of us don't have a stratum 0 source. My LAN sees a stratum 2 server.

                      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
                      • D
                        darkonc @maverickws
                        last edited by

                        @maverickws That's no big surprise. The 2.* rule is for 2.*.pool.ntp.org . Other organizations / domains can do whatever they want.

                        maverickwsM 1 Reply Last reply Reply Quote 0
                        • maverickwsM
                          maverickws @darkonc
                          last edited by

                          @darkonc was that for me?

                          1 Reply Last reply Reply Quote 0
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