man/yaboot.conf.5

.\" Copyright (c) 2001 Ethan Benson <erbenson@alaska.net>
.\" Portions of this manual page from silo.conf documentation
.\" Copyright (c) 1999 Jakub Jelinek <jakub@redhat.com>
.\" Portions of this manual page from lilo.conf documentation
.\" Copyright (c) 1992-1998 Werner Almesberger
.\" This program is distributed according to the Gnu General Public License.
.\" See the file COPYING in the ybin source distribution.
.\"
.TH YABOOT.CONF 5 "28 October 2001" "GNU/Linux PowerPC" "File Formats"
.SH NAME
.B yaboot.conf
\- Configuration file format used by
.BR yaboot (8)
and
.BR ybin (8).
.SH SYNOPSIS
.BI "/boot/yaboot.conf"
.SH DESCRIPTION
The \fByaboot.conf\fP file is a configuration file for \fByaboot\fP
which is read during booting, and for \fBybin\fR(8) to generate a boot
menu and to properly install \fByaboot\fP onto the \fBbootstrap\fP(8)
partition.

\fByaboot.conf\fP provides instructions for \fByaboot\fP. This
includes which kernels to load and what options to pass to them.
\fByaboot\fP reads and parses its configuration file found on the
\fBbootstrap\fR(8) partition on PowerMacs, and directly from the root
filesystem on IBM PowerPC hardware.  On PowerMacs you must run the
\fBybin\fR(8) command each time you modify \fB/boot/yaboot.conf\fR.

\fByaboot\fP is able to boot kernels even without this configuration file or
if this file is crippled or contains syntax errors, but the user has to
enter full OpenFirmware names and full path of the images to load and all options
required for them manually.
.SH "FILE FORMAT"
The file consists of comments and variable assignments.
.TP
Comments
Start with a \fI#\fP character, and continue to
the end of the line.
.TP
Flag variables
Consist of a single keyword and are followed by whitespace
or the end of the file.
.TP
String variables
Consist of the variable name, optional whitespace, a
\fI=\fP character, optional whitespace, the value and required
newline.  IMPORTANT: \fBybin\fR(8) specific options do not support
embedded spaces.  It is important that there be no trailing whitespace
at the end of a line.
.TP
File names
Some string variables are expecting file names. A file name format in \fByaboot\fP
is:

  [<devicename>][<part>]<absolute_pathname>

  or

  [<devicename>][<part>][\fB[\fP<m>\fB-\fP<n>\fB]\fP]

The first form refers to a file or directory on some supported filesystem
(currently \fIext2\fP, \fIhfs\fP, \fIhfs+\fP or \fIiso9660\fP), the latter
refers to a range of 512B blocks on a device. For a device block range,
either <devicename>, or <part>, or [<m>-<n>] must be given.

Optional <devicename> is the OpenFirmware name of the device the file or range
is located on. See below for its syntax. For OpenFirmware the device
name must be immediately followed by the \fI:\fP character. The default is
the boot device yaboot was booted from, or the value of \fIdevice=\fR
in \fB/boot/yaboot.conf\fR.

Optional <part> is the 1 based partition number on the device. First
partition is 1 (e.g. on \fI/dev/sda\fP in Linux is this \fI/dev/sda1\fP).
The default is the default partition (the value of the \fIpartition\fP
variable in the config file).  Note that on Apple partition tables the
first partition is always the partition table itself (/dev/sda1 is the
partition table).

<absolute_pathname> must start with a \fI/\fP character and is the
pathname from the root of the filesystem on that device (unless it is the
root filesystem this is different to the pathname you will see in GNU/Linux).

<m> is the first block number (in blocksize 512 bytes) of the range to
be loaded and <n> is the last block number plus one.
.TP
Device name syntax is:

  <fully_qualified_prom_device_name>[\fB:\fP<part_number>]

where the fully qualified OpenFirmware device name starts with a
\fI/\fP character for the root of the OpenFirmware device tree and
contains all the nodes from the root in the tree up to the disk device
node. If some node contains more than one child node with the same
name and the path has to go through such node, a \fI@\fP character
followed by hexadecimal address pair is desirable to resolve the
ambiguity. Optional partition number is a number that follows the
\fI:\fP character \fI1\fP (for first partition) \fI2\fP (for second,
partition, etc). OpenFirmware device names might look like:

  /pci@80000000/pci-bridge@d/ADPT,2930CU@2/@0:
  /pci/@d/mac-io/ata-3@20000/disk@1:
  /pci/@d/pci-ata@1/ata-4@0/disk@0:
  /pci/@d/pci-ata@1/ata-4@0/disk@1:

OpenFirmware device names if specified as part of the file name (see above)
should be followed by the \fI:\fP character to separate the device name from
the optional Linux partition number, as shown above.  For more information on
this topic, consult
.BR bootstrap (8).

OpenFirmware also has some predefined aliases which are used instead
of the longer canonical device names.  Standard aliases include:

   hd: - The primary master IDE hard disk.
   ultra1: - The primary slave IDE hard disk.
   cd: - The secondary master device (usually CDROM).
   zip: - The secondary slave device (usually zip drive).
.PP
Variable names are case sensitive, values of string variables are also
case sensitive.

Blanks and equal signs may only be part of a variable name or a value if
they are escaped by a backslash or if the value is embedded in double
quotes. An equal sign may not be the only character in a name or value.

An escaped tab is converted to an escaped blank. An escaped newline is
removed from the input stream. An escaped backslash (i.e. two
backslashes) is converted to a backslash. Inside quoted strings, only
double quotes, backslashes and newlines can be escaped.

Example:

  # Simple yaboot.conf
  boot=/dev/hda2
  device=hd:
  partition=3
  magicboot=/usr/local/lib/yaboot/ofboot
  timeout=50
  root=/dev/hda3
  read-only
  # End of global variables - begin image labels
  image=/boot/vmlinux
    label=linux
  image=/boot/vmlinux.old
    label=old

This file contains options for two distinct programs: the
\fBybin\fR(8) (and \fBmkofboot\fR(8)) \fBbootstrap\fR(8) installer, and the
\fByaboot\fR(8) bootloader, each ignores the other's configuration
options.

The \fBybin\fR/\fBmkofboot\fR options are:
.B boot=
.B ofboot=
.B install=
.B magicboot=
.B delay=
.B bsd=
.B macos=
.B macosx=
.B darwin=
.B defaultos=
.B usemount
.B mntpoint=
.B fstype=
.B hfstype=
.B nobless
.B hide
.B protect
.B nonvram
.B enablecdboot
.B enablenetboot
.B enableofboot
.B brokenosx

The remaining options belong to \fByaboot\fR(8).
.SH "GLOBAL OPTIONS"
\fB/boot/yaboot.conf\fP begins with a possibly empty global options section.
This section contains all variable assignments up to the first \fIimage\fP
setting.

The following global options are recognized:
.TP
.BI "boot=" boot-device
Specifies the \fBbootstrap\fR(8) partition \fBybin\fR(8) will install
the boot loader on.  This partition needs to have an HFS or MSDOS
filesystem created on it (except on IBM hardware).  \fBybin\fR(8) will
not create a filesystem.  If a filesystem is not present run
\fBmkofboot\fR(8) instead of \fBybin\fR(8) for the first time. The
\fBbootstrap\fR(8) partition must have a partition type of
Apple_Bootstrap to prevent MacOS[X] from mounting it.  If MacOS is able
to mount the \fBbootstrap\fR(8) partition it will make it unbootable
by removing the attributes \fBybin\fR(8) set to make the partition
bootable by OpenFirmware.  The \fBbootstrap\fR partition must not be
mounted anywhere on your filesystem, \fBybin\fR(8) and
\fBmkofboot\fR(8) will refuse to operate on it if it is mounted.  On
IBM hardware the \fBbootstrap\fR(8) should be a type 0x41 PReP Boot
partition.
.TP
.BI "ofboot=" of-path
This option defines the OpenFirmware device path to the
\fBbootstrap\fR(8) partition.  This is needed so the first stage
\fIofboot.b\fR loader can be configured properly.  It should include
the OpenFirmware path including the partition number (but not a
filename). Example: if your bootstrap partition is /dev/hda2 the OF
path will likely be hd:2.  As of \fBybin\fR(8) 0.18 you no longer are
required to (and should not) specify this option.  If left undefined
\fBybin\fR(8) will attempt to figure out the OpenFirmware path
automatically using the \fBofpath\fR(8) utility.  You should only need
to define this option if \fBofpath\fR(8) fails.
.TP
.BI "install=" boot-loader
Specifies the path to the \fByaboot\fR(8) OpenFirmware executable
file.  This file is copied by \fBybin\fR(8) to the \fBbootstrap\fR(8)
partition.  The default if this is not specified is
\fI/usr/local/lib/yaboot/yaboot\fR or \fI/usr/lib/yaboot/yaboot\fR.
.TP
.BI "magicboot=" magicboot-script
Specifies the path to an OpenFirmware CHRP script that \fBybin\fR(8)
will copy to the \fBbootstrap\fR(8) partition.  Such a script contains
Forth commands that can allow you to do interesting things such as
creating a boot menu to choose between MacOS or GNU/Linux.  Currently
you must use a magicboot script do to a bug in OpenFirmware.
Eventually a CHRP header could be added to the \fByaboot\fR(8)
executable so this can be optional.  When this option is defined the
magicboot script will be executed by OF automatically at boot (instead
of the \fBinstall\fR file.)  See man \fBbootstrap\fR(8) for more
information on this.  As of ybin 0.22 you should set this to
/usr/local/lib/yaboot/ofboot which is a autoconfiguring first stage
loader for yaboot.  It is capable of presenting a dual boot menu for
GNU/Linux, MacOS and MacOSX.  If dual booting is not required or
configured it will simply load yaboot directly.  You must specify this
for most PowerMacs or they will fail to boot.  You cannot use
magicboot scripts with IBM hardware.
.TP
.BI "default=" name
Uses the specified image as the default boot image. If `default' is omitted,
the image appearing first in the configuration file is used.
.TP
.BI "defaultos=" linux|bsd|macos|macosx|darwin
Defines the default OS for the first stage boot menu to load, by
default this is linux, which really means \fByaboot\fR.
Valid values are: linux, bsd, macos, macosx, and
darwin.  This is only relevant if you have \fIbsd=\fR, \fImacos=\fR,
\fImacosx=\fR, or \fIdarwin=\fR options defined.
.TP
.BI "message=" message_filename
Specifies a file containing a message that is displayed before the
boot prompt.  You may specify either a plain pathname, in which case
the default device and partition will be derived from the
\fIdevice=\fR and \fIpartition=\fR lines in the global section of
\fByaboot.conf\fR, or you can specify a full OpenFirmware device path,
the file may be on any \fByaboot\fR(8) supported filesystem.  The message
file must be plain ASCII text with UNIX newlines.  Note: only the
first 2000 bytes of this file will be read.
.TP
.BI "password=" password
Protect booting by a password. The password is given in either
cleartext or an md5 hash (of the same format as used in GNU/Linux
passwd files)in the configuration file.  Because of that, the
configuration file should be only readable by the superuser and the
password should differ if possible from other passwords on the system.
See
.BR chmod (1)
to set permissions on
.BR yaboot.conf (5).
Passwords currently do not affect the boot menu entries
(\fImacos=\fR, \fImacosx=\fR, etc).
.TP
.BI "timeout=" tsecs
Sets a timeout (in tenths of a second) for keyboard input. If no key is
pressed for the specified time, the first image is automatically booted.
.TP
.BI "delay=" secs
Sets a timeout (in seconds) for an OS choice in the first stage
\fIofboot\fR loader.  If no key is pressed for the specified time, the
default OS defined by \fIdefaultos=\fR (or GNU/Linux) is automatically
booted.  If this is left unset, the value of \fItimeout=\fR (converted
to seconds) will be used.
.TP
.BI "init-code=" string
Specifies that \fByaboot\fR(8) should call OpenFirmware to
execute the string given (a series of forth commands) before printing
the boot prompt.
.TP
.BI "fgcolor=" string
Specifies the foreground (text) color used by \fByaboot\fR(8) and the
boot menu.  Available colors are: black, blue, light-blue, green,
light-green, cyan, light-cyan, red, light-red, purple, light-purple,
brown, light-gray, dark-gray, yellow, and white.  The default is white.
.TP
.BI "bgcolor=" string
Specifies the background color used by \fByaboot\fR(8) and the
mulitboot menu.  Available colors are: black, blue, light-blue, green,
light-green, cyan, light-cyan, red, light-red, purple, light-purple,
brown, light-gray, dark-gray, yellow, and white.  The default is
black.
.TP
.BI "bsd=" of-path
The OpenFirmware or Unix device path to a NetBSD or OpenBSD root
partition, this partition must have the BSD kernel located at \fI/bsd\fR.
You must also have the BSD bootloader
\fIofwboot\fR installed at \fI/usr/local/lib/yaboot/ofwboot\fR,
\fBybin\fR(8) will install this onto the \fBbootstrap\fR(8) partition.
When you define this option you will be presented with a simple menu at
bootup allowing you to hit L to boot GNU/Linux or B to boot BSD (along
with other choices if configured).  This will only work if you are
using the new \fI/usr/local/lib/yaboot/ofboot\fR script.  When this is
set to a unix device node (ie \fI/dev/hda11\fR) then ybin will use the
\fBofpath\fR(8) utility to determine the OpenFirmware device path.
.TP
.BI "macos=" of-path
The OpenFirmware or Unix device path to a MacOS 8.* or 9.* boot
partition.  When you define this option you will be presented with a
simple menu at bootup allowing you to hit L to boot GNU/Linux or M to
boot MacOS (along with other choices if configured).  This will only
work if you are using the new \fI/usr/local/lib/yaboot/ofboot\fR
script.  When this is set to a unix device node (ie \fI/dev/hda11\fR)
then ybin will use the \fBofpath\fR(8) utility to determine the
OpenFirmware device path.
.TP
.BI "macosx=" of-path
The OpenFirmware or unix device path to a MacOS X boot partition.
When you define this option you will be presented with a simple menu
at bootup allowing you to hit L to boot GNU/Linux or X to boot MacOSX
(along with other choices if configured).  This will only work if you
are using the new \fI/usr/local/lib/yaboot/ofboot\fR script.  When
this is set to a unix device node (ie \fI/dev/hda11\fR) then ybin will
use the \fBofpath\fR(8) utility to determine the OpenFirmware device
path.
.TP
.B "brokenosx"
This option causes the menu entry for MacOSX to execute
\\System\\Library\\CoreServices\\BootX from the macosx=device instead
of the usual \\\\:tbxi.  This is necessary if OSX is installed onto an
HFS+ filesystem instead of UFS. When OSX is installed on an HFS+
filesystem MacOS will mount and debless the OSX partition.  Add this
option if the OSX menu entry breaks after booting MacOS.  You should
not use this option if OSX is installed on a UFS filesystem, for UFS
installs you specify the OSX bootstrap partition which is protected
against MacOS.  This option requires \fImacosx=\fR to be set.
.TP
.BI "darwin=" of-path
The OpenFirmware or unix device path to a Darwin boot partition.
When you define this option you will be presented with a simple menu
at bootup allowing you to hit L to boot GNU/Linux or D to boot Darwin
(along with other choices if configured).  This will only work if you
are using the new \fI/usr/local/lib/yaboot/ofboot\fR script.  When
this is set to a unix device node (ie \fI/dev/hda11\fR) then ybin will
use the \fBofpath\fR(8) utility to determine the OpenFirmware device
path.
.TP
.B "enablecdboot"
This option adds an entry to the boot menu to boot from the CDROM drive.
.TP
.B "enablenetboot"
This option adds an entry to the boot menu to boot from the network.
.TP
.B "enableofboot"
This option adds an entry to the boot menu to boot into an OpenFirmware
prompt.
.TP
.B "usemount"
This option causes \fBybin\fR to use the regular \fBmount\fR(8)
utilities to access the filesystem on the \fBbootstrap\fR(8) partition
instead of the userspace \fBhfsutils\fR(1).  This is not recommended
for HFS filesystems since it is not possible to set all the attributes
required for automatic OpenFirmware booting.  If you use this option
you will have to modify OpenFirmware's boot-device variable to make
your machine bootable (see man \fBbootstrap\fR(8)).  Without this option
you can normally reset OpenFirmware to its default configuration and
your system will boot automatically into GNU/Linux. (See
\fBbootstrap\fR(8) for details) This option is required for MSDOS
filesystems.
.TP
.BI "mntpoint=" /path/to/directory
Requires \fIusemount\fR this works exactly like usemount does except it
does not mount the \fBbootstrap\fR(8) partition but rather installs the
bootloader into the directory defined as the mountpoint.  The pathname
MUST be clean, ie no embedded spaces or metacharacters.  The directory
may not be more then one subdirectory deep from the root of the
partition (not necessarily the unix /).  You must not have a trailing
/ either.  This option is NOT recommended since it has the same
limitations as usemount, your system will not be bootable by
OpenFirmware, it will only be manually bootable or bootable if you
change the boot-device variable to the direct pathname to the
bootloader (which \fBybin\fR(8) will attempt to do).  WARNING: This
option is not secure if untrusted users can write to the value of
\fImntpoint=\fR, and the filesystem supports links.
.TP
.BI "fstype=" hfs|msdos|raw
Specifies what kind of filesystem is created on the \fBbootstrap\fR(8)
partition by \fBmkofboot\fR(8).  It must be either \fIhfs\fR or
\fImsdos\fR or \fIraw\fR.  For Apple PowerMacs HFS is the only
workable option unless you have partitioned your disk with Intel
partition tables. \fBYbin\fR(8) also uses this option to determine how
to access the partition properly.  The \fIraw\fR type causes
\fBybin\fR(8) or \fBmkofboot\fR(8) to copy the bootloader (value of
\fIinstall=\fR) to the \fBbootstrap\fR(8) partition without any
filesystem. CAUTION: this will destroy any data or filesystem on the
\fBbootstrap\fR(8) partition (value of \fIboot=\fR) if you specify
something like \fIboot=/dev/sda\fR you will destroy the partition
table and lose ALL data on the disk. The default if omitted, is hfs.
.TP
.BI "hfstype=" type-code
Specifies the four character HFS type code that is given to the boot
loader (or magicboot script).  The default is \fItbxi\fR and should
not be changed unless you really know what you are doing, OpenFirmware
(on PowerMacs) looks for a file of this type to execute as a boot
loader so if you change this your system will not boot automatically.
This is only meant for users who must use a MacOS boot partition as
the bootstrap partition, otherwise the conflict of two \fItbxi\fR
files could potentially cause MacOS to fail to boot.  This code is
only given to the file intended for OpenFirmware to boot.  This option
is ignored on non-HFS filesystems.
.TP
.B "nobless"
This prevents \fBybin\fR(8) from \*(lqblessing\*(rq the root directory of
the \fBbootstrap\fR(8) partition.  Blessing the root directory is required
for OpenFirmware to boot correctly.  This should only be used when a
MacOS boot partition is being used as the \fBbootstrap\fR(8) in which case
blessing the root directory would make MacOS unbootable.  If you use
this option you must manually configure OpenFirmware to boot
\fByaboot\fR(8).  (see \fBbootstrap\fR(8))
.TP
.B "hide"
This causes \fBybin\fR(8) to set the HFS invisible bit on all the boot
loader files.  OpenFirmware ignores this bit, but MacOS will not show
invisible files in the Finder.  This is useful if the \fBbootstrap\fR(8)
partition is MacOS mountable and you want to prevent annoying MacOS
lusers from screwing up your GNU/Linux boot loader ;-). This option is
ignored for non-HFS filesystems.
.TP
.B "protect"
This causes \fBybin\fR(8) to set the HFS/MSDOS read-only bit on all the boot
loader files.  MacOS will not allow a read-only file to be modified or
deleted (but does not prevent anyone from removing this bit) This is
only useful if the \fBbootstrap\fR(8) partition is MacOS mountable and
you want to discourage modification/deletion of the boot loader.
.TP
.B "nonvram"
This option prevents \fBybin\fR(8) from setting the OpenFirmware
boot-device variable with \fBnvsetenv\fR(8).
.PP
In addition to these global options, per-image options \fIappend\fP,
\fIdevice\fP, \fIimage\fP, \fIinitrd-prompt\fP, \fIinitrd-size\fP,
\fIinitrd\fP, \fIpartition\fP, \fIpause-after\fP, \fIpause-message\fP,
\fIramdisk\fP, \fIread-only\fP, \fIread-write\fP, \fIroot\fP and
\fIrestricted\fR can be specified in the global section. They are used
as defaults if they aren't specified in the configuration sections of
the respective kernel images and will be used also for the arbitrary
images specified on the input line and not mentioned in the
configuration file (unless overridden by input line options).
.SH "PER-IMAGE SECTIONS"
A per-image section starts with either a line

  \fBimage=\fP\fIfilename\fP

(for booting from files)
From the \fIimage\fP line on until next \fIimage\fP line are variable
assignments and flags for this image's section. The following options
and flags are recognized:
.TP
.BI "label=" name
The bootloader uses the main file name (without its path) of each image
specification to identify that image. A different name can be used by
setting the variable `label'.
.TP
.BI "alias=" name
A second name for the same entry can be used by specifying an alias.
.TP
.BI "partition=" part_no
Specifies the default partition number (a digit, hda1 is part_no 1) to
be used if some filename does not specify a partition number
explicitly.  The kernel images should be located on the root
filesystem, thus \fIpartition\fR should usually be set to the root
partition number.  For example if the root partition is /dev/hda3 (the
third partition), then \fIpartition\fR should be set to
\fIpartition=3\fR.
.TP
.BI "device=" device_name
Specifies the default device name to be used if some filename does not
specify a device name explicitly. This defaults to the device
\fByaboot\fP has been booted from if you don't specify \fIdevice\fP in either
the global section or per-image section of the config file.
.TP
.BI "append=" string
Appends the options specified to the parameter line
passed to the kernel. This is typically used to
specify parameters of hardware that can't be
entirely auto-detected or for which probing may be
dangerous. Example:

  append = "video=ofonly"
.TP
.BI "literal=" string
Like `append', but removes all other options (e.g. setting of the root
device). Because vital options can be removed unintentionally with
`literal', this option cannot be set in the global options section.
.TP
.BI "ramdisk=" size
This specifies the size of the optional RAM disk. A value of zero indicates
that no RAM disk should be created. If this variable is omitted, the RAM
disk size configured into the boot image is used.
.TP
.BI "read-only"
This specifies that the root file system should be mounted read-only.
Typically, the system startup procedure re-mounts the root file system
read-write later (e.g. after fsck'ing it).
.TP
.BI "read-write"
This specifies that the root file system should be mounted read-write.
.TP
.BI "root=" root-device
This specifies the device that should be mounted as root.
.TP
.BI "initrd=" filename
Specifies the file that will be loaded at boot time as the initial RAM disk.
Example:

  initrd=/images/initrd.img

yaboot will not decompress the initial ramdisk, the Linux kernel will do that.
If the initial ramdisk does not fit on one media (usually floppy), you can
split it into several pieces and separate the filenames in the list by
\fI|\fP characters. In this case, you have to provide a non-zero
\fIinitrd-size\fP and, if the images reside on different medias,
\fIinitrd-prompt\fP as well.
Example (on the first floppy is initrd1.img, on the second initrd2.img
always in the root directory and the sum of both image sizes is 1700000
bytes):

  initrd=/initrd1.img|/initrd2.img
  initrd-size=1700000
  initrd-prompt
.TP
.BI "initrd-size=" size
When more than one initial ramdisk part is specified in the \fIinitrd\fP
setting, this option is required to be the sum of sizes of all the images
mentioned on that line, in bytes. It is required so that yaboot can reserve
space for the image, even though size of some parts has not been determined
yet.
.TP
.BI "initrd-prompt"
If more than one initial ramdisk part is specified, wait for user pressing a
key between loading the different images, so that the user can exchange
media. This flag is needed if some initrd parts reside on the same device,
but different removable media. On the other side, if you e.g. load one part
from a floppy and the second part from a hard disk, such option is not
needed (the question is who'd write something like that into yaboot.conf).
.TP
.BI "pause-after"
If this flag is specified, yaboot will stop after loading the kernel (and
initial ramdisks if specified) and ask the user to press a key before
continuing.
.TP
.BI "pause-message=" string
If \fIpause-after\fP is specified, this variable specifies the string to
print to the user when asking him to press a key. The default is:

  Press ENTER to continue.
.TP
.BI "sysmap=" filename
Specifies the path for the System.map file that goes with the kernel
image (\fIimage=\fR).  This is for 2.4 kernels with a kernel debugger only.
.TP
.BI "single-key"
Enables booting the image by hitting a single key when the cursor is at the
first character in the input line, without the need to press <ENTER>
afterwards. \fIsingle-key\fP requires that either the image's label or its
alias (or both) is a single character. If you need to specify parameters for
such an image, or if you want to boot some other image which happens to
start with the same letter, then you need to start the input line with at
least one space which will be removed before processing but will disable
this single-key feature.
.TP
.BI "restricted"
Restricted limits the ability to customize command line arguments.
\fIrestricted\fR has no effect if \fIpassword=\fR is not specified.
A password is only required to boot the image specified in
\fB/boot/yaboot.conf\fP if parameters are specified on the command line
or if the user enters an image that is not specified in the configuration
file at all (arbitrary file load).  For an image not including
the \fIrestricted\fR keyword (unless \fIrestricted\fR is in the global
section), the password will be required.  If \fIrestricted\fR
is in the global section, all boot labels act as above (duh:).
.SH EXAMPLES
Here is an example \fIyaboot.conf\fR file:
.IP
.nf
boot=/dev/hda2
device=hd:
root=/dev/hda3
partition=3
timeout=20
install=/usr/local/lib/yaboot/yaboot
magicboot=/usr/local/lib/yaboot/ofboot
fgcolor=black
bgcolor=green
default=Linux
defaultos=linux
password=secret

image=/boot/vmlinux
	label=Linux
	read-only
	restricted

image=/boot/vmlinux.old
	label=linux.old
	read-only

macos=hd:9
macosx=/dev/hda10
.fi
.SH NOTES
The format defined in this man page will not work with versions of
\fByaboot\fR(8) older then 0.6.  The color options only work with
yaboot 1.0 and later.
.SH BUGS
Some
.B yaboot
options may not be implemented fully.
.SH AUTHORS
This man page was derived from \fBsilo.conf\fR(5) written by Jakub
Jelinek and the SparcLinux team, and modified for
\fByaboot\fR(8)/\fBybin\fR(8) by Ethan Benson.
.P
\fByaboot\fR(8) was written by Benjamin Herrenschmidt <benh@kernel.crashing.org>.
.P
\fBybin\fR(8) was written by Ethan Benson <erbenson@alaska.net>.
.SH SEE ALSO
.BR bootstrap (8),
.BR chmod (1),
.BR hfsutils (1),
.BR mkofboot (8),
.BR mount (8),
.BR nvsetenv (8),
.BR ofpath (8),
.BR yaboot (8),
.BR ybin (8).