20 systemctl Command Line Examples for System and Service Management

On modern Linux distributions such as Ubuntu, Debian, CentOS, Rocky Linux, and Fedora, systemctl is the primary command-line tool used to control and manage services. It is part of systemd, the default init system for most Linux servers today.

In this article, we will cover 20 essential systemctl commands that every Linux administrator, DevOps engineer, and system operator should know.

What Is systemctl?

systemctl is a command-line utility used to interact with systemd units, including:

• Services (.service)
• Sockets (.socket)
• Timers (.timer)
• Targets (.target)
• Mount points (.mount)

It allows you to start, stop, restart, enable, disable, and monitor services efficiently.

1. Check Service Status

systemctl status nginx

Displays detailed information about the nginx service, including its current state, logs, and process ID.

2. Start a Service

sudo systemctl start apache2

Starts the Apache web server immediately.

3. Stop a Service

sudo systemctl stop apache2

Stops the Apache service gracefully.

4. Restart a Service

sudo systemctl restart sshd

Restarts the SSH service, useful after configuration changes.

5. Reload a Service Configuration

sudo systemctl reload nginx

Reloads the service configuration without interrupting active connections.

6. Enable a Service at Boot

sudo systemctl enable docker

Configures Docker to start automatically during system boot.

7. Disable a Service at Boot

sudo systemctl disable docker

Prevents Docker from starting automatically at boot time.

8. List All Active Services

systemctl list-units --type=service

Shows all currently running services.

9. List All Loaded Units

systemctl list-units

Displays all loaded systemd units, not limited to services.

10. List Installed Unit Files

systemctl list-unit-files

Shows all installed unit files and their enablement state.

11. Display Detailed Unit Information

systemctl show sshd

Outputs all properties and runtime details of the SSH service.

12. Mask a Service

sudo systemctl mask apache2

Completely prevents a service from being started, even manually.

13. Unmask a Service

sudo systemctl unmask apache2

Removes the mask and allows the service to start again.

14. List Failed Services

systemctl --failed

Displays all services that failed to start or crashed.

15. Check System Boot Status

systemctl is-system-running

Shows whether the system is fully operational, degraded, or still booting.

16. Enable and Start a Service Immediately

sudo systemctl enable --now nginx

Enables the service at boot and starts it right away.

17. Reboot the System

sudo systemctl reboot

Reboots the system using systemd.

18. Power Off the System

sudo systemctl poweroff

Safely shuts down the system.

19. Switch to Rescue Mode

sudo systemctl rescue

Enters rescue mode for system recovery and troubleshooting.

20. Isolate a Target

sudo systemctl isolate multi-user.target

Switches the system to multi-user (non-graphical) mode.

Useful systemctl Tips

• Always check service status before restarting:

  systemctl status <service>

• After editing unit files, reload systemd:

  sudo systemctl daemon-reload

• Use journalctl together with systemctl for log analysis.

Conclusion

Mastering systemctl is essential for anyone managing Linux servers. With these 20 systemctl command-line examples, you can confidently control services, diagnose system issues, and manage system behavior efficiently.

Whether you are a system administrator, DevOps engineer, or Linux enthusiast, understanding systemctl will significantly improve your operational workflow.