System and processes

The `systemctl` command

Manages the system's services (units): start, stop, check whether they are active and decide whether they start with the machine.

Syntax

systemctl {status|start|stop|restart|enable|disable|is-active|is-enabled|list-units} UNIDAD

Most useful options

statusShows whether it is active, since when and its PID

start / stopRuns or stops it right now

enable / disableDecides whether it starts at boot

is-active / is-enabledAnswer active/inactive and enabled/disabled

$ systemctl status sshIs the ssh server active?

$ sudo systemctl restart nginxRestart it after changing the config

$ systemctl enable sshMake it start with the machine

$ systemctl list-units --allEvery unit

You can try them in the browser terminal: it does not touch your computer.

start is now and enable is at boot: you can have an active but disabled service (or the opposite).
Changing the state needs sudo.
The short name works: ssh is ssh.service.

What is the difference from service?

systemctl is the modern system (systemd); service is the old way, still supported.

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