shutdown - Man Page

• Power off ([h]alt) immediately: shutdown -h now
• Reboot immediately: shutdown [-r|--reboot] now
• Reboot in 5 minutes: shutdown [-r|--reboot] +5 &
• Shutdown at 1:00 pm (Uses 24h clock): shutdown -h 13:00
• [c]ancel a pending shutdown/reboot operation: shutdown -c

tldr.sh

shutdown [Options...] [TIME] [WALL...]

shutdown may be used to halt, power off, or reboot the machine​.

The first argument may be a time string (which is usually "now")​. Optionally, this may be followed by a wall message to be sent to all logged-in users before going down​.

The time string may either be in the format "hh:mm" for hour/minutes specifying the time to execute the shutdown at, specified in 24h clock format​. Alternatively it may be in the syntax "+m" referring to the specified number of minutes m from now​. "now" is an alias for "+0", i​.e​. for triggering an immediate shutdown​. If no time argument is specified, "+1" is implied​.

The time string specifies the earliest point in time the shutdown may take place; it is a lower bound only: the shutdown is executed as soon as possible, but not before the specified time​. Specifying a time that already elapsed (for example an "hh:mm" time earlier today) is not an error and results in an immediate shutdown​. See the discussion of --when= in systemctl(1) for details​.

Note that to specify a wall message you must specify a time argument, too​.

If the time argument is used, 5 minutes before the system goes down the /run/nologin file is created to ensure that further logins shall not be allowed​.

The following options are understood:

--help

Print a short help text and exit​.

-H,  --halt

Halt the machine​.

-P,  --poweroff

Power the machine off (the default)​.

-r,  --reboot

Reboot the machine​.

-h

The same as --poweroff, but does not override the action to take if it is "halt"​. E​.g​. shutdown --reboot -h means "poweroff", but shutdown --halt -h means "halt"​.

-k

Do not halt, power off, or reboot, but just write the wall message​.

--no-wall

Do not send wall message before halt, power off, or reboot​.

-c

Cancel a pending shutdown​. This may be used to cancel the effect of an invocation of shutdown with a time argument that is not "+0" or "now"​.

--show

Show a pending shutdown action and time if there is any​.

Added in version 250​.

On success, 0 is returned, a non-zero failure code otherwise​.

The shutdown command in previous init systems (including sysvinit) defaulted to single-user mode instead of powering off the machine​. To change into single-user mode, use systemctl rescue instead​.

systemd(1), systemctl(1), halt(8), wall(1)

apccontrol(8), kexec(8), last(1), login(1), nologin(5), openrc(8), poweroff(8), reboot(2), sudo(8), systemd.directives(7), systemd.index(7), wall(1).