BOOT(8) | System Manager's Manual (landisk) | BOOT(8) |
boot
, boot.conf
— landisk-specific second-stage bootstrap
The main purpose of this program is to load the system kernel from the root file system of the machine.
As described in boot_landisk(8), this program is loaded by the xxboot(8) primary bootstrap loader and provides a convenient way to load the kernel. This program acts as an enhanced boot monitor for landisk systems, providing a common interface for the kernel to start from.
Basic operations include:
The sequence of its operation is as follows: initialization,
parsing the configuration file, then an interactive command line. While at
the command line you have 5 seconds to type any commands, if needed. If time
expires, the kernel will be loaded according to the current variable
settings (see the set
command). Each time a kernel
load fails, the timeout is increased by one second. The sequence of
boot
operations is as follows:
boot
was loaded from, open and parse
it. Lines beginning with the ‘#’ character, as well as
whitespace at the beginning of lines, are ignored. The file may contain
any commands boot
accepts at the interactive
prompt. Though default settings usually suffice, they can be changed
here.>> OpenBSD/landisk BOOT
[x.xx]
is displayed to the active console, where
x.xx is the version number of the
boot
program, followed by the
boot>
prompt, which means you are in interactive mode and may enter
commands. If you do not, boot
will proceed to
load the kernel with the current parameters after the timeout period has
expired.
By default, boot
attempts to load the
kernel executable /bsd. If it fails to find the
kernel and no alternative kernel image has been specified, the system will
be unable to boot.
The following commands are accepted at the
boot
prompt:
-acds
]boot
variables will be used.
The only bootable device, at the moment, is the internal IDE device (either a compactflash media or an ATA disk drive), and is named ‘cf’. Therefore, to boot kernel /bsd from the internal drive, specify “boot cf:/bsd”.
-a
root
device
to use.-c
-d
-s
addr
debug
boot
was compiled with DEBUG
defined.howto
image
timeout
Boot the default kernel:
boot> boot
Remove the 5 second pause at boot-time permanently, causing
boot
to load the kernel immediately without
prompting:
# echo "boot" >
/etc/boot.conf
Boot the kernel named /bsd.rd in
“User Kernel Configuration” mode (see
boot_config(8)). This
mechanism allows for the explicit enabling and disabling of devices during
the current boot sequence, as well as the modification of device parameters.
Once booted, such changes can be made permanent by using
config(8)'s
-e
option.
boot> boot cf:/bsd.rd
-c
gzip(1), autoconf(4), ddb(4), boot_config(8), boot_landisk(8), fdisk(8), reboot(8), xxboot(8)
This program was written by Michael Shalayeff for OpenBSD 4.1.
September 10, 2015 | OpenBSD-6.1 |