# ln -sf /lib/systemd/system/multi-user.target /etc/systemd/system/default.target
Restore to GUI mode:
# ln -sf /lib/systemd/system/graphical.target /etc/systemd/system/default.target
Switch to 'runlevel 3' by running
systemctl isolate multi-user.target
Or 'runlevel 5' by
systemctl isolate graphical.target
Set default
systemctl set-default multi-user.target
systemctl get-default
Manage services:
systemctl [start|stop|restart|status|enable|disable] foo
hostnamectl set-hostname fedora
firewall-cmd --permanent --zone=home --add-port=29418/tcp
firewall-cmd --permanent --zone=home --add-source="130.245.126.112"
firewall-cmd --permanent --zone=home --add-service=http