1.\" $NetBSD: shutdown.8,v 1.33 2016/09/14 00:16:31 kre 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 September 12, 2016 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 Ddfhknprvxz 41.Op Fl b Ar bootstr 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 poweroff 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 v 114To enable verbose messages on the console, pass 115.Fl v 116to 117.Xr reboot 8 118or 119.Xr halt 8 . 120.It Fl x 121To enable debugging messages on the console, pass 122.Fl x 123to 124.Xr reboot 8 125or 126.Xr halt 8 . 127.It Fl z 128To silence some shutdown messages on the console, pass 129.Fl z 130to 131.Xr reboot 8 132or 133.Xr halt 8 . 134.It Fl D 135Prevents 136.Nm 137from detaching from the tty with 138.Xr fork 2 Ns / 139.Xr exit 3 . 140.It Ar time 141.Ar Time 142is the time at which 143.Nm 144will bring the system down and 145may be the word 146.Ar now 147or a future time in one of two formats: 148.Ar +number , 149or 150.Ar [[[[[cc]yy]mm]dd]hh]mm , 151where the century, year, month, day, and hour may be defaulted 152to the current system values. 153The first form brings the system down 154.Ar number 155minutes from the current time; the second brings the system down at the 156absolute time specified. 157If the century is not specified, it defaults to 1900 for years between 69 158and 99, or 2000 for years between 0 and 68. 159A leading zero in the 160.Dq yy 161value is 162.Em not 163optional. 164.It Ar message ... 165Any other arguments comprise the warning message that is broadcast 166to users currently logged into the system. 167.It Ar - 168If 169.Ar - 170is supplied as the only argument after the time, the warning message is read 171from the standard input. 172.El 173.Sh BEHAVIOR 174.Pp 175At intervals, becoming more frequent as apocalypse approaches 176and starting at ten hours before shutdown, warning messages are displayed 177on the terminals of all users logged in. 178Five minutes before shutdown, or immediately if shutdown is in less 179than 5 minutes, logins are disabled by creating 180.Pa /etc/nologin 181and copying the warning message there. 182If this file exists when a user attempts to log in, 183.Xr login 1 184prints its contents and exits. 185The file is removed just before 186.Nm 187exits. 188.Pp 189At shutdown time, a message is written in the system log containing the 190time of shutdown, who initiated the shutdown, and the reason. 191Next a message is printed announcing the start of the system shutdown hooks. 192Then the shutdown hooks in 193.Pa /etc/rc.shutdown 194are run, and a message is printed indicating that they have completed. 195After a short delay, 196.Nm 197runs 198.Xr halt 8 199or 200.Xr reboot 8 , 201or sends a terminate 202signal to 203.Xr init 8 204to bring the system down to single-user mode, depending on the choice 205of options. 206.Pp 207The time of the shutdown and the warning message are placed in 208.Pa /etc/nologin 209and should be used to tell the users why the system is 210going down, when it will be back up, and to share any other pertinent 211information. 212.Sh FILES 213.Bl -tag -width /etc/rc.shutdown -compact 214.It Pa /etc/nologin 215tells 216.Xr login 1 217not to let anyone log in 218.It Pa /fastboot 219tells 220.Xr rc 8 221not to run 222.Xr fsck 8 223when rebooting 224.It Pa /etc/rc.shutdown 225System shutdown commands 226.El 227.Sh SEE ALSO 228.Xr login 1 , 229.Xr wall 1 , 230.Xr fastboot 8 , 231.Xr halt 8 , 232.Xr init 8 , 233.Xr poweroff 8 , 234.Xr reboot 8 , 235.Xr rescue 8 236.Sh BACKWARD COMPATIBILITY 237The hours and minutes in the second time format may be separated by 238a colon (``:'') for backward compatibility. 239.Sh HISTORY 240A 241.Nm 242command was originally written by Ian Johnstone for UNSW's modified 243.At "6th Edn" , 244modified, and then incorporated in 245.Bx 4.1 . 246