1.\" $OpenBSD: boot.8,v 1.13 2023/02/23 19:48:22 miod Exp $ 2.\" 3.\" Copyright (c) 1997-2001 Michael Shalayeff 4.\" 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.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18.\" IN NO EVENT SHALL THE AUTHOR OR HIS RELATIVES BE LIABLE FOR ANY DIRECT, 19.\" INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 20.\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 21.\" SERVICES; LOSS OF MIND, USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 23.\" STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 24.\" IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 25.\" THE POSSIBILITY OF SUCH DAMAGE. 26.\" 27.\" 28.Dd $Mdocdate: February 23 2023 $ 29.Dt BOOT 8 landisk 30.Os 31.Sh NAME 32.Nm boot , 33.Nm boot.conf 34.Nd landisk-specific second-stage bootstrap 35.Sh DESCRIPTION 36The main purpose of this program is to load the system kernel from the 37root file system of the machine. 38.Pp 39This program is loaded by the 40.Xr xxboot 8 41primary bootstrap loader and provides a convenient way to load the kernel. 42This program acts as an enhanced boot monitor for landisk systems, providing 43a common interface for the kernel to start from. 44.Pp 45Basic operations include: 46.Pp 47.Bl -bullet -compact 48.It 49Loading kernels from any device supported by your system firmware. 50.It 51Loading kernels compressed by 52.Xr gzip 1 . 53.It 54Providing an interactive command line. 55.El 56.Pp 57The sequence of its operation is as follows: initialization, 58parsing the configuration file, then an interactive command line. 59While at the command line you have 5 seconds to type any commands, if needed. 60If time expires, the kernel will be loaded according to 61the current variable settings (see the 62.Ic set 63command). 64Each time a kernel load fails, the timeout is increased by one second. 65The sequence of 66.Nm 67operations is as follows: 68.Bl -enum 69.It 70If the file 71.Pa /etc/boot.conf 72exists on the filesystem 73.Nm 74was loaded from, open and parse it. 75Lines beginning with the 76.Sq # 77character, 78as well as whitespace at the beginning of lines, 79are ignored. 80The file may contain any commands 81.Nm 82accepts at the interactive prompt. 83Though default settings usually suffice, they can be changed here. 84.\" XXX CHECK_SKIP_CONF is not defined... 85.\" .Pa boot.conf 86.\" processing can be skipped by holding down either Control key as 87.\" .Nm 88.\" starts. 89.It 90The header line 91.Pp 92.Dl >> OpenBSD/landisk BOOT [x.xx] 93.Pp 94is displayed to the active console, where 95.Ar x.xx 96is the version number of the 97.Nm 98program, followed by the 99.Pp 100.Dl boot> 101.Pp 102prompt, which means you are in interactive mode and may enter commands. 103If you do not, 104.Nm 105will proceed to load the kernel with the current parameters after the 106timeout period has expired. 107.El 108.Pp 109By default, 110.Nm 111attempts to load the kernel executable 112.Pa /bsd . 113If it fails to find the kernel and no alternative kernel image has 114been specified, the system will be unable to boot. 115.Sh COMMANDS 116The following commands are accepted at the 117.Nm 118prompt: 119.Bl -tag -width shorten 120.It Ic boot Oo Oo Ar device : Oc Ns Ar image Oc Op Fl acds 121Boots the specified kernel image 122with any options given. 123If 124.Ar device 125or 126.Ar image 127are omitted, values from 128.Nm 129variables will be used. 130.Pp 131The only bootable device, at the moment, is the internal IDE device (either a 132compactflash media or an ATA disk drive), and is named 133.Sq cf . 134Therefore, to boot kernel 135.Pa /bsd 136from 137.\" XXX no support for partition different from `a' yet... 138.\" slice 139.\" .Sq a 140.\" on 141the internal drive, specify 142.Dq boot cf:/bsd . 143.Bl -tag -width _a_ 144.It Fl a 145Causes the kernel to ask for the 146.Nm root 147device to use. 148.It Fl c 149Causes the kernel to go into 150.Xr boot_config 8 151before performing 152.Xr autoconf 4 153procedures. 154.It Fl d 155Causes the kernel to drop into 156.Xr ddb 4 157at the earliest convenient point. 158.It Fl s 159Causes the kernel to boot single-user. 160.El 161.It Ic echo Op Ar args 162Displays 163.Ar args 164on the console device. 165.It Ic help 166Prints a list of available commands. 167.It Ic hexdump Ar addr size 168Show 169.Ar size 170bytes of memory at address 171.Ar addr . 172.It Ic ls Op Ar directory 173Prints contents of the specified 174.Ar directory 175in long format including: attributes and file type, owner, group, 176size, filename. 177.It Ic reboot 178Reboots the machine by initiating a warm boot procedure. 179.It Ic set Op Ar varname Op Ar value 180If invoked without arguments, prints a list of variables and their values. 181If only 182.Ar varname 183is specified, displays contents of that variable. 184If 185.Ar varname 186and 187.Ar value 188are both specified, sets that variable to the given value. 189Variables include: 190.Pp 191.Bl -tag -compact -width db_console 192.It Ic db_console 193Boolean (0 or 1) to permit entry into the kernel debugger before the 194.Em ddb.console 195sysctl gets effective. 196.It Ic debug 197Debug flag if 198.Nm 199was compiled with DEBUG defined. 200.\" XXX Useless until partitions are supported. 201.\" .It Nm device 202.\" Boot device name (e.g., 203.\" .Li cf0a , 204.\" .Li cf0d ) . 205.It Ic howto 206Options to pass to the loaded kernel. 207.It Ic image 208File name containing the kernel image. 209.It Ic timeout 210Number of seconds boot will wait for human intervention before 211booting the default kernel image. 212.It Ic time 213Displays system time and date. 214.El 215.Sh FILES 216.Bl -tag -width /usr/mdec/xxboot -compact 217.It Pa /boot 218system bootstrap 219.It Pa /etc/boot.conf 220system bootstrap's startup file 221.It Pa /bsd 222kernel image 223.It Pa /bsd.rd 224kernel image for installation/recovery 225.It Pa /usr/mdec/xxboot 226first stage bootstrap 227.El 228.Sh EXAMPLES 229Boot the default kernel: 230.Pp 231.Dl boot> boot 232.Pp 233Remove the 5 second pause at boot-time permanently, causing 234.Nm 235to load the kernel immediately without prompting: 236.Pp 237.Dl # echo \&"boot\&" > /etc/boot.conf 238.Pp 239Boot the kernel named 240.Pa /bsd.rd 241in 242.Dq User Kernel Configuration 243mode (see 244.Xr boot_config 8 ) . 245This mechanism allows for the explicit enabling and disabling of devices 246during the current boot sequence, as well as the modification 247of device parameters. 248Once booted, such changes can be made permanent by using 249.Xr config 8 Ns 's 250.Fl e 251option. 252.Pp 253.Dl boot> boot cf:/bsd.rd -c 254.Sh SEE ALSO 255.Xr gzip 1 , 256.Xr autoconf 4 , 257.Xr ddb 4 , 258.Xr boot_config 8 , 259.Xr fdisk 8 , 260.Xr reboot 8 , 261.Xr xxboot 8 262.Sh HISTORY 263This program was written by Michael Shalayeff for 264.Ox 4.1 . 265