1. What is timedatectl?
A) timedatectl is a command-line utility in systemd-based Linux systems used to query and change system clock, time zone, and NTP (network time synchronization) settings.
2. How do you check the current system time ?
A)
timedatectl
It displays local time, universal time, RTC time, time zone, and NTP status.
3. How do you list available time zones?
A)
timedatectl list-timezones
4. How do you change the time zone with timedatectl?
A)
timedatectl set-timezone Asia/Kolkata
5. How do you set the system time manually with timedatectl?
A)
timedatectl set-time "2025-09-19 16:30:00"
6. What is the difference between system time and RTC (hardware clock)?
A)
- System time: Software clock maintained by the kernel.
- RTC (Hardware clock): Time maintained by the BIOS/firmware, independent of OS.
7. How do you check if NTP synchronization is enabled using timedatectl?
A)
timedatectl show | grep NTPSynchronized
or simply:
timedatectl
Look for NTP service and System clock synchronized.
8. How do you enable NTP synchronization?
A)
timedatectl set-ntp true
9. How do you disable NTP synchronization?
A)
timedatectl set-ntp false
10. What is the difference between timedatectl and date command?
A)
- date: Shows or sets the system time only.
- timedatectl: Manages time, date, timezone, RTC, and NTP settings (more advanced).
11. How do you check only the current timezone using timedatectl?
A)
timedatectl show --property=Timezone
12. What happens when you change the time zone with timedatectl?
A) It updates the system time zone symlink at /etc/localtime to point to the selected zone in /usr/share/zoneinfo/.
13. How do you set only the date with timedatectl?
A)
timedatectl set-time "2025-09-19"
14. How do you set only the time with timedatectl?
A)
timedatectl set-time "18:45:00"
15. How do you check the RTC (hardware clock) time with timedatectl?
A)
timedatectl | grep "RTC time"