1.\" $NetBSD: shutdown.8,v 1.28 2008/10/21 02:35:51 lukem Exp $ 2.\" 3.\" Copyright (c) 1988, 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. Neither the name of the University nor the names of its contributors 15.\" may be used to endorse or promote products derived from this software 16.\" without specific prior written permission. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.\" @(#)shutdown.8 8.2 (Berkeley) 4/27/95 31.\" 32.Dd October 21, 2008 33.Dt SHUTDOWN 8 34.Os 35.Sh NAME 36.Nm shutdown 37.Nd close down the system at a given time 38.Sh SYNOPSIS 39.Nm 40.Op Fl b Ar bootstr 41.Op Fl Ddfhknpr 42.Ar time 43.Op Ar message ... | Ar - 44.Sh DESCRIPTION 45.Nm 46provides an automated shutdown procedure for super-users 47to nicely notify users when the system is shutting down, 48saving them from system administrators, hackers, and gurus, who 49would otherwise not bother with such niceties. 50.Pp 51Available friendlinesses: 52.Bl -tag -width bootstr 53.It Fl b Ar bootstr 54The given 55.Ar bootstr 56is passed to 57.Xr reboot 8 58for the benefit of those systems that can pass boot arguments to the 59firmware. 60Currently, this only affects sun3 and sparc machines. 61.It Fl d 62.Nm 63will pass the 64.Fl d 65flag to 66.Xr reboot 8 67or 68.Xr halt 8 69to request a kernel core dump. 70If neither the 71.Fl h 72or 73.Fl r 74flags are specified, then 75.Fl d 76also implies 77.Fl r . 78.It Fl f 79.Nm 80arranges, in the manner of 81.Xr fastboot 8 , 82for the file systems 83.Em not to be 84checked on reboot. 85.It Fl h 86The system is halted at the specified 87.Ar time , 88using 89.Xr halt 8 . 90.It Fl k 91Kick everybody off. 92The 93.Fl k 94option 95does not actually halt the system, but leaves the 96system multi-user with logins disabled (for all but super-user). 97.It Fl n 98Prevent the normal 99.Xr sync 2 100before stopping. 101.It Fl p 102The system is powered down at the specified 103.Ar time , 104using 105.Xr halt 8 . 106If the powerdown fails, or the system does not support software powerdown, 107the system will simply halt instead. 108.It Fl r 109The system is rebooted at the specified 110.Ar time , 111using 112.Xr reboot 8 . 113.It Fl D 114Prevents 115.Nm 116from detaching from the tty with 117.Xr fork 2 Ns / 118.Xr exit 3 . 119.It Ar time 120.Ar Time 121is the time at which 122.Nm 123will bring the system down and 124may be the word 125.Ar now 126or a future time in one of two formats: 127.Ar +number , 128or 129.Ar [[[[[cc]yy]mm]dd]hh]mm , 130where the century, year, month, day, and hour may be defaulted 131to the current system values. 132The first form brings the system down 133.Ar number 134minutes from the current time; the second brings the system down at the 135absolute time specified. 136If the century is not specified, it defaults to 1900 for years between 69 137and 99, or 2000 for years between 0 and 68. 138A leading zero in the 139.Dq yy 140value is 141.Em not 142optional. 143.It Ar message ... 144Any other arguments comprise the warning message that is broadcast 145to users currently logged into the system. 146.It Ar - 147If 148.Ar - 149is supplied as the only argument after the time, the warning message is read 150from the standard input. 151.El 152.Sh BEHAVIOR 153.Pp 154At intervals, becoming more frequent as apocalypse approaches 155and starting at ten hours before shutdown, warning messages are displayed 156on the terminals of all users logged in. 157Five minutes before shutdown, or immediately if shutdown is in less 158than 5 minutes, logins are disabled by creating 159.Pa /etc/nologin 160and copying the warning message there. 161If this file exists when a user attempts to log in, 162.Xr login 1 163prints its contents and exits. 164The file is removed just before 165.Nm 166exits. 167.Pp 168At shutdown time, a message is written in the system log containing the 169time of shutdown, who initiated the shutdown, and the reason. 170Next a message is printed announcing the start of the system shutdown hooks. 171Then the shutdown hooks in 172.Pa /etc/rc.shutdown 173are run, and a message is printed indicating that they have completed. 174After a short delay, 175.Nm 176runs 177.Xr halt 8 178or 179.Xr reboot 8 , 180or sends a terminate 181signal to 182.Xr init 8 183to bring the system down to single-user mode, depending on the choice 184of options. 185.Pp 186The time of the shutdown and the warning message are placed in 187.Pa /etc/nologin 188and should be used to tell the users why the system is 189going down, when it will be back up, and to share any other pertinent 190information. 191.Sh FILES 192.Bl -tag -width /etc/rc.shutdown -compact 193.It Pa /etc/nologin 194tells 195.Xr login 1 196not to let anyone log in 197.It Pa /fastboot 198tells 199.Xr rc 8 200not to run 201.Xr fsck 8 202when rebooting 203.It Pa /etc/rc.shutdown 204System shutdown commands 205.El 206.Sh SEE ALSO 207.Xr login 1 , 208.Xr wall 1 , 209.Xr fastboot 8 , 210.Xr halt 8 , 211.Xr init 8 , 212.Xr poweroff 8 , 213.Xr reboot 8 , 214.Xr rescue 8 215.Sh BACKWARD COMPATIBILITY 216The hours and minutes in the second time format may be separated by 217a colon (``:'') for backward compatibility. 218.Sh HISTORY 219The 220.Nm 221command appeared in 222.Bx 4.0 . 223