systemctl チートシート（Ubuntu）
systemd のユニット（サービス）操作。
状態・一覧
systemctl status nginx.service
systemctl list-units --type=service --state=running
systemctl --failed
起動・停止・再起動
sudo systemctl start nginx.service
sudo systemctl stop nginx.service
sudo systemctl restart nginx.service
sudo systemctl reload nginx.service
ブート時の有効・無効
sudo systemctl enable nginx.service
sudo systemctl disable nginx.service
sudo systemctl daemon-reload