Provided by: systemd-sysv_257.9-0ubuntu2_amd64 

NAME
poweroff, reboot, halt - Power off, reboot, or halt the machine
SYNOPSIS
poweroff [OPTIONS...]
reboot [OPTIONS...]
halt [OPTIONS...]
DESCRIPTION
poweroff, reboot, and halt may be used to power off, reboot, or halt the machine. All three commands take
the same options.
OPTIONS
The following options are understood:
--help
Print a short help text and exit.
Added in version 253.
--halt
Halt the machine, regardless of which one of the three commands is invoked.
Added in version 253.
-p, --poweroff
Power off the machine, when either halt or poweroff is invoked. This option is ignored when reboot is
invoked.
Added in version 253.
--reboot
Reboot the machine, regardless of which one of the three commands is invoked.
Added in version 253.
-f, --force
Force immediate power-off, halt, or reboot. If specified, the command does not contact the init
system. In most cases, filesystems are not properly unmounted before shutdown. For example, the
command reboot -f is mostly equivalent to systemctl reboot -ff, instead of systemctl reboot -f.
Added in version 253.
-w, --wtmp-only
Only write wtmp shutdown entry, do not actually power off, reboot, or halt.
Added in version 253.
-d, --no-wtmp
Do not write wtmp shutdown entry.
Added in version 253.
-n, --no-sync
Do not sync hard disks/storage media before power-off, reboot, or halt.
Added in version 253.
--no-wall
Do not send wall message before power-off, reboot, or halt.
Added in version 253.
EXIT STATUS
On success, 0 is returned, a non-zero failure code otherwise.
NOTES
These commands are implemented in a way that preserves basic compatibility with the original SysV
commands. systemctl(1) verbs poweroff, reboot, halt provide the same functionality with some additional
features.
Note that on many SysV systems halt used to be synonymous to poweroff, i.e. both commands would equally
result in powering the machine off. systemd is more accurate here, and halt results in halting the
machine only (leaving power on), and poweroff is required to actually power it off.
SEE ALSO
systemd(1), systemctl(1), shutdown(8), wall(1)
systemd 257.9 POWEROFF(8)