1) List all units controlled by systemd
# systemctl
or
#systemctl list-units
2) List all _active_ services on the system
# systemctl list-units -t service
3) list all service on the system
# systemctl list-units -t service --all
4) Check service status
# systemctl status sshd.service
5) Start Service
# systemctl start sshd.service
6) Stop Service
# systemctl stop sshd.service
7) Enable Service
# systemctl enable sshd.service
8) Disable Service
# systemctl disable sshd.service
9) You can view service dependencies with the command
# systemctl list-dependencies
10) Systemd is also used to halt/reboot/hibernate/shutdown
check systemctl --help for commands which are available.
Systemd uses cgroups extensively and groups processes started by a particular service into its own groups. This means that killing a service will get all processes started by a particular service.
References:
http://www.linux.com/learn/tutorials/527639-managing-services-on-linux-with-systemd
