shell-things/etc/chrony
Aminda Suomalainen 6f0184b519
chrony/sources/ntppool: enable xleave
From https://community.ntppool.org/t/chrony-conf-noclientlog-vs-clientloglimit/2263/4 I got the impression it's fine to do and the manual says it's compatible with the basic mode and xleave supporting servers may still reply in basic mode sometimes so this shouldn't break anything
2024-04-29 06:51:27 +03:00
..
conf.d chrony/conf.d: add .FIXME suffix to ca-certificates.conf, clarifying comments 2023-11-16 20:19:39 +02:00
sources.d chrony/sources/ntppool: enable xleave 2024-04-29 06:51:27 +03:00
README.md run prettier 2023-02-21 17:54:39 +02:00
chrony.conf chrony: cut chrony.d/ into conf.d/ and sources.d/ 2021-01-29 12:56:38 +02:00

README.md

Chrony config files

For some reason Debian package for Chrony doesnt include other config files so that has to be done by hand like

confdir /etc/chrony/chrony.d

Windows

Refer to ../../Windows/time/README.md

Other random notes

On pools, the default maxsources is 4 and pools would be resolved until there would be 4 names while the documentation for Telia and Snopyta says they have only 3. Cloudflare again resolves to two per IP version, so I assume that means 2.

Commands of interest:

Chrony itself

Note: -N uses names specified in config instead of reverse name lookupping then.

  • chrony -N activity - what sources are doing
  • chrony -N authdata - can show that server uses NTS
  • chrony -N ntpdata - a lot of data on the servers
  • chronyc offline - offline mode
  • chronyc online - reconnects servers
  • chrony -N sources - used timeservers and their statuses
  • chrony -N tracking - local status (stratum and own clock etc.)

nmap

Checking that something is an NTP server? Needs root:

nmap -sU -p 123 --script=ntp-info 192.168.0.1

Checking that something has NTS?

nmap -p 4460 -Pn ntp.example.net

In GitHub user jauderhos curated NTS list user cadusilva suggests this command instead:

chronyd -Q -t 3 'server NTP_SERVER_HERE iburst nts maxsamples 1'

Firewall configuration

In case local clients or peers are wanted,

ufw allow from 192.168.0.0/16 to any port 123 proto udp
ufw allow from fe80::/10 to any port 123 proto udp

A bit wide 192.168.x.x, but so is conf.d/local-servers,conf and fe80://10 isnt ULA either.