systemctl commands
check status
all services status
systemctl statusfor one service
systemctl status <service_name>check failed
systemctl --failedalso by state
systemctl list-units --state failedmanage service
stop a service
systemctl stop <service_name>start a service
systemctl start <service_name>restart a service
systemctl restart <service_name>reload a service with out stop/start/restart
systemctl reload <service_name>