Linux Tips: Mastering systemctl — Control Services & Boot Targets Like a Pro
A practical cheat-sheet for managing services, targets, and power states on systemd-based Linux distributions.
Why systemctl?
systemctl is the main command to manage systemd units (services, sockets, timers, targets, and more). With it, you can start/stop services, set what runs at boot, switch boot targets, and even manage power states.
Essential Service Commands
systemctl start unit.serviceStart a service.
systemctl stop unit.serviceStop a running service.
systemctl restart unit.serviceRestart the service.
systemctl status unit.serviceShow active state and recent logs.
systemctl is-active unit.serviceIs it running? Returns active or inactive.
systemctl enable unit.serviceStart automatically at boot.
systemctl disable unit.serviceDo not start at boot.
systemctl is-enabled unit.serviceCheck if enabled (0 = yes, 1 = no).
Inspect & Discover Services
systemctl list-unit-files --type=serviceList available services on the system.
systemctl list-units --type=serviceShow currently active services.
Boot Targets (Runlevels, the systemd way)
Switch the current session or set the default boot target:
systemctl isolate multi-user.targetSwitch to multi-user (non-graphical, like runlevel 3).
systemctl set-default multi-user.targetMake multi-user the default boot target.
systemctl get-defaultShow the current default target.
| Classic Runlevel | systemd Target | Description |
|---|---|---|
| 3 | multi-user.target | Non-graphical, multi-user (servers/CLI) |
| 5 | graphical.target | Graphical login (desktop) |
| 1 | rescue.target | Single-user rescue mode |
Power Management
systemctl suspendLow-power suspend.
systemctl hibernateSave RAM to disk, power off.
Pro Tips
- Most commands require
sudo(or root). - Use
systemctl status <unit>to see logs; for deeper logs, tryjournalctl -u <unit>. - Unit names often end in
.service, but systemd manages many types (timers, sockets, targets, etc.).
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good job
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