[Install] WantedBy=multi-user.target This is the mechanism by which one unit can ask to be added to the Wants= of another when it is installed. i.e., when

[Install] WantedBy=multi-user.target This is the mechanism by which one unit can ask to be added to the Wants= of another when it is installed. i.e., when you run 'systemctl enable whatever.service', it will be symlinked into '/etc/systemd/system/multi-user.target.wants'. And 'systemctl show multi-user.target' will show 'whatever.service' in its Wants property. https://www.freedesktop.org/software/systemd/man/systemd.unit.html#%5BInstall%5D%20Section%20Options https://www.freedesktop.org/software/systemd/man/systemd.uni... During bootup of a headless system, the 'default' target is usually multi-user.target, so what we've done here is ensure that whatever.service will be started before the machine finishes booting. https://www.freedesktop.org/software/systemd/man/bootup.html https://www.freedesktop.org/software/systemd/man/bootup.html