1.\" Copyright (c) 1990, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)reboot.8 8.1 (Berkeley) 6/9/93 33.\" $FreeBSD$ 34.\" 35.Dd June 9, 1993 36.Dt REBOOT 8 37.Os 38.Sh NAME 39.Nm reboot , 40.Nm halt , 41.Nm fastboot , 42.Nm fasthalt 43.Nd stopping and restarting the system 44.Sh SYNOPSIS 45.Nm halt 46.Op Fl lnqp 47.Op Fl k Ar kernel 48.Nm 49.Op Fl dlnqp 50.Op Fl k Ar kernel 51.Nm fasthalt 52.Op Fl lnqp 53.Op Fl k Ar kernel 54.Nm fastboot 55.Op Fl dlnqp 56.Op Fl k Ar kernel 57.Sh DESCRIPTION 58The 59.Nm halt 60and 61.Nm 62utilities flush the filesystem cache to disk, send all running processes 63a 64.Dv SIGTERM 65(and subsequently a 66.Dv SIGKILL ) 67and, respectively, halt or restart the system. 68The action is logged, including entering a shutdown record into the 69.Xr wtmp 5 70file. 71.Pp 72The options are as follows: 73.Bl -tag -width indent 74.It Fl d 75The system is requested to create a crash dump. This option is 76supported only when rebooting, and it has no effect unless a dump 77device has previously been specified with 78.Xr dumpon 8 . 79.It Fl k Ar kernel 80Boot the specified 81.Ar kernel 82on the next system boot. If the kernel boots successfully, the 83.Em default 84kernel will be booted on succesive boots, this is a one-shot option. 85If the boot fails, the system will continue attempting to boot 86.Ar kernel 87until the boot process is interrupted and a valid kernel booted. 88This may change in the future. 89.It Fl l 90The halt or reboot is 91.Em not 92logged to the system log. 93This option is intended for applications such as 94.Xr shutdown 8 , 95that call 96.Nm 97or 98.Nm halt 99and log this themselves. 100.It Fl n 101The filesystem cache is not flushed. 102This option should probably not be used. 103.It Fl q 104The system is halted or restarted quickly and ungracefully, and only 105the flushing of the filesystem cache is performed (if the 106.Fl n 107is not specified). 108This option should probably not be used. 109.It Fl p 110The system will turn off the power 111if it can. 112This is of course likely to make 113.Nm 114rather similar to 115.Nm halt . 116.El 117.Pp 118The 119.Nm fasthalt 120and 121.Nm fastboot 122utilities are nothing more than aliases for the 123.Nm halt 124and 125.Nm 126utilities. 127.Pp 128Normally, the 129.Xr shutdown 8 130utility is used when the system needs to be halted or restarted, giving 131users advance warning of their impending doom and cleanly terminating 132specific programs. 133.Sh SEE ALSO 134.Xr wtmp 5 , 135.Xr boot 8 , 136.Xr dumpon 8 , 137.Xr savecore 8 , 138.Xr shutdown 8 , 139.Xr sync 8 140.Sh HISTORY 141A 142.Nm 143command appeared in 144.At v6 . 145