systemd shutdown 8 shutdown Halt, power off or reboot the machine 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. 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 -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. On success, 0 is returned, a non-zero failure code otherwise. systemd1, systemctl1, halt8, wall1