Search notes:

systemctl list-units

Show running services:
$ systemctl list-units --type=service --state=running
  UNIT                      LOAD   ACTIVE SUB     DESCRIPTION
  atd.service               loaded active running Deferred execution scheduler
  cron.service              loaded active running Regular background program processing daemon
  dbus.service              loaded active running D-Bus System Message Bus
  getty@tty1.service        loaded active running Getty on tty1
  mdmonitor.service         loaded active running MD array monitor
  nginx.service             loaded active running A high performance web server and a reverse proxy server
  ssh.service               loaded active running OpenBSD Secure Shell server
  systemd-journald.service  loaded active running Journal Service
  systemd-logind.service    loaded active running User Login Management
  systemd-timesyncd.service loaded active running Network Time Synchronization
  systemd-udevd.service     loaded active running Rule-based Manager for Device Events and Files
  user@1000.service         loaded active running User Manager for UID 1000

LOAD   = Reflects whether the unit definition was properly loaded.
ACTIVE = The high-level unit activation state, i.e. generalization of SUB.
SUB    = The low-level unit activation state, values depend on unit type.
12 loaded units listed.

See also

systemctl

Index