Operations grimoire/NTP
NTP allows to sync time. That's especially important for accurate logs and TLS certificates.
Recommended NTP servers
There is a CC list of servers by country. France makes sense for most servers to use the country of the datacenter where the server is located.
By OS
NTP is configured in core.
FreeBSD
We use ntpd service. Each day, drift from NTP servers is checked by periodic 480.status-ntpd.
We have enabled the automatic startup of the ntpd service on all FreeBSD servers to ensure continuous time synchronization. Additionally, the ntpd configuration has been adjusted to allow automatic connections to time sources, ensuring reliable updates without any manual intervention.
For reference, see:
- Default NTP configuration leads to connection refused[Default NTP configuration leads to connection refused
]
Linux
Chrony service is used.
Troubleshoot
Update leap seconds
Leap seconds file isn't maintained any more by NTP package (see upstream issue)
To update the file, run the hotfix:
$ salt -G 'os:FreeBSD' state.apply hotfixes/leap-seconds.sls
ntpq: read: Connection refused
Reported as T2192. The ntpq command queries a specific NTP server, here localhost:123. If the connection can't be established, it probably means ntpd service isn't started.
NTP status: ntpq: read: Connection refused
Solution: service ntpd start
References
- NTP
- NTP servers in France
- Bug 3898 - update leap seconds file
- Chrony
