systemctl Command Cheat Sheet

systemctl is the central management tool for controlling the init system (systemd).

Synopsis

systemctl [OPTIONS...] COMMAND [UNIT...]

sudo systemctl start nginx
sudo systemctl stop nginx
sudo systemctl restart nginx
sudo systemctl reload nginx

sudo systemctl enable nginx
sudo systemctl disable nginx

Enable links the service file to the boot target.

systemctl status nginx

Shows: Loaded state, Active state, Main PID, and recent logs.

systemctl is-active nginx
systemctl is-enabled nginx

systemctl list-units --type=service

systemctl list-units --type=service --all

Find what crashed on boot.

systemctl --failed

systemctl reboot
systemctl poweroff
systemctl suspend

systemctl rescue

Safely edit a service unit override.

sudo systemctl edit nginx

Creates: /etc/systemd/system/nginx.service.d/override.conf.

For specific service (wrapper around journalctl).

systemctl status nginx -l

Completely forbid a service from starting (even manually or by dependency).

sudo systemctl mask nginx

(Unmask with unmask).

Who needs this service?

systemctl list-dependencies nginx --reverse

Who does this service need?

systemctl list-dependencies nginx

List active timers.

systemctl list-timers

Daemon Reload: If you manually edit unit files in /lib/systemd/ or /etc/systemd/, you must run:
```
sudo systemctl daemon-reload
```