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

[Sergei_Shablovsky]

@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!

[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

[maverickws]

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

[compuguy]

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

[RobbieTT]

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.

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[JKnott]

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.

[RobbieTT]

@jknott

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

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[JKnott]

@robbiett

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

[darkonc]

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

[maverickws]

@darkonc was that for me?