Learn to inspect, correct and synchronize system time reliably using timedatectl and related tools. 10.12.2025 | reading time: 3 min Timedatectl is the systemd utility that lets an administrator inspect and change the system clock, timezone and NTP synchronization; it solves common problems such as wrong timezone, unsynchronized clocks, and RTC mismatches quickly and from the shell. Fix a timezone mismatch Show the current state and then change the timezone and enable NTP with concrete commands and their expected output: ```sh $ timedatectl status Local time: Thu 2025-12-10 14:30:00 CET Universal time: Thu 2025-12-10 13:30:00 UTC RTC time: Thu 2025-12-10 13:30:00 Time zone: Etc/UTC (UTC, +0000) System clock synchronized: no NTP service: inactive ``` Find and set the correct zone, then enable network time: ```sh $ timedatectl list-timezones | grep -i berlin Europe/Berlin $ timedatectl set-timezone Europe/Berlin $ timedatectl set-ntp true $ timedatectl status Time zone: Europe/Berlin (CET, +0100) System clock synchronized: yes NTP service: active ``` Handle clock quirks and advanced commands Timedatectl can also set the system clock directly, declare the hardware clock as localtime, and reveal detailed properties — for example use `timedatectl set-time "2025-12-10 14:45:00"` to set time manually, `timedatectl set-local-rtc 1` if the RTC uses localtime, and `timedatectl show --property=NTPSynchronized` to query sync state; stop or disable your NTP client before forcing the clock to avoid fights between services, and remember to propagate changes to the hardware clock with `hwclock --systohc` when required. When timedatectl meets other daemons Timedatectl is a front-end that reports and controls time-related systemd features, but actual synchronization is performed by services such as systemd-timesyncd, chronyd or ntpd; choose the daemon that fits the environment, ensure only one time-sync service runs, and use `timedatectl` to check the global state while configuring the chosen daemon for performance or network-specific options. Keep time correct at boot A consistent time at boot prevents certificate errors, log confusion and database issues; combine a correct timezone, an enabled NTP client, and a synchronized RTC to ensure services start with the right clock, then automate verification in init scripts or monitoring to detect regressions early. Certification-minded next step Practise these commands and scenarios on a test machine to build muscle memory: run checks, switch timezones, toggle NTP and observe effects on RTC and services; deepen this knowledge toward certifications like CompTIA Linux+ or LPIC-1 and consider intensive exam preparation at bitsandbytes.academy to turn hands-on skill into a credential. Join Bits & Bytes Academy First class LINUX exam preparation. setup network utilities boot-process troubleshooting
