How do I check server time, timezone and clock synchronisation?
Time accuracy and timezone display are related but different. A correct UTC clock can be displayed in different local timezones, while an unsynchronised clock can cause authentication, certificate and scheduling failures. Inspect the active time service before enabling another one or manually changing the clock.
Before you start
- An authorised SSH session on the Linux server.
Instructions
1. Read the displayed and UTC time
Compare the server’s timestamp with the incident timeline. Always include an offset or explicitly use UTC when exchanging logs with another team.
date -Is
date -u -Is
timedatectl statusOn systemd systems, timedatectl shows timezone and synchronisation indicators. An enabled NTP service is not, by itself, proof of accurate synchronisation.
2. Inspect the active synchronisation service
If chrony is the configured client, its read-only tracking output provides the selected time source and clock error information. Use the equivalent status tool for a different installed client.
chronyc trackingRequires chrony. Check its leap status, reference source and offset rather than changing time based on one unexplained reading.
Check the result
- The timestamp is correct, the intended timezone is configured and the active client reports a healthy time source. Application-specific timezone settings may still require separate review.
Troubleshooting
- Clock synchronisation is inactive
- Identify the configured client, its service state and allowed network path before changing settings.
- Logs appear an hour apart
- Check timezone offsets and daylight-saving display before assuming the underlying clocks disagree.
Official references
Use the documentation for your installed version when a flag, service name or platform feature differs.