shutdown(8)shutdown(8)Nameshutdown - close down the system at a given time
Syntax
/etc/shutdown [ -k ] [ -r ] [ -h ] [ -o ] time [ warning-message ... ]
Description
The command provides an automated shutdown procedure that a superuser
can use to notify users when the system is shutting down.
The time is the time at which will bring the system down. It may be
the word `now', indicating an immediate shutdown, or specify a future
time in one of two formats: + number or hour : min. The first form
brings the system down in number minutes. The second brings the system
down at the time of day indicated, using a 24-hour clock format.
At intervals which get shorter as shutdown nears, warning messages are
displayed at the terminals of all users on the system. Warning mes‐
sages are also sent to users who are logged in to a remote system that
has mounted a file system or directory from the local system using NFS.
Five minutes before shutdown, or immediately if shutdown is timed for
less than five minutes, logins are disabled by creating and writing a
message there. If this file exists when a user attempts to log in,
prints its contents and exits. The file is removed just before exits.
At shutdown time, a message is written in the file This message con‐
tains the time of shutdown, who ran shutdown, and the reason. Then, a
terminate signal is sent at to bring the system to single-user state.
If the or options are used, then executes or avoids shutting the system
down (respectively). The option is for use by only. It indicates to
that it is being called by and not to return to the user.
You should place the time of the shutdown and the warning message in
Use the message to inform the users about when the system will be back
up and why it is going down.
Restrictions
You can kill the system only between now and 23:59, if you use the
absolute time for shutdown.
Files
Tells login not to let anyone log in
Log file for successful shutdowns
See Alsologin(1), wall(1), halt(8), opser(8), reboot(8), rwalld(8c)shutdown(8)
