[rrq/maintain_lilo.git] / man / lilo.conf.5

'\" t
.\" @(#)lilo.conf.5 1.0 950728 aeb
.\" This page is based on the lilo docs, which carry the following
.\" COPYING condition:
.\"
.\" LILO program code, documentation and auxiliary programs are
.\" Copyright 1992-1998 Werner Almesberger.
.\" Extensions to LILO, documentation and auxiliary programs are
.\" Copyright 1999-2005 John Coffman.
.\" All rights reserved by the respective copyright holders.
.\" 
.\" Redistribution and use in source and binary forms of parts of or the
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.\"
.TH LILO.CONF 5 "July 2010"
.SH NAME
lilo.conf \- configuration file for lilo
.SH DESCRIPTION
.LP
This file, by default
.IR /etc/lilo.conf ,
is read by the boot loader installer 'lilo' (see lilo(8)).
.LP
It might look as follows:
.IP
.nf
# lilo.conf
#
#  global options:
boot=/dev/hda
prompt
timeout=150
lba32
compact
vga=normal
root=/dev/hda1
read-only
menu-title=" John's Computer "
#
#  bootable kernel images:
image=/boot/zImage-1.5.99
     label=try
image=/boot/zImage-1.0.9
     label=1.0.9
image=/tamu/vmlinuz
     label=tamu
     initrd=initramdisk.img
     root=/dev/hdb2
     vga=ask
#
#  other operating systems:
other=/dev/hda3
     label=dos
     boot-as=0x80    # must be C:
other=/dev/hdb1
     label=Win98
     boot-as=0x80    # must be C:
other=/dev/hdb5
     label=os2
     loader=os2_d
     table=E:   # os2 sees as E:
.fi
.LP
This configuration file specifies that lilo uses the Master
Boot Record on /dev/hda. (For a discussion of the various ways
to use lilo, and the interaction with other operating systems,
see user.tex from the lilo documentation.)
.LP
When booting, the boot loader will issue its 
.I "boot:"
prompt and wait for you to enter the label of the kernel (and any options)
which you wish to boot. At any time you may hit [Tab] to see
a list of kernel/other labels.
Alternately, if the \fBmenu\fP boot loader is installed,
a menu of boot options will be presented for your selection.
The title of this menu is overridden with the menu
title specification in this configuration file.
If you enter nothing,
then the default kernel image, the first mentioned, (/boot/zImage-1.5.99)
will be booted after a timeout of 15 seconds (150 deciseconds).
There may be at least 16 images mentioned in lilo.conf. (The exact number depends
upon compilation options.)
.LP
As can be seen above, a configuration file starts with a number
of global options (the top 9 lines in the example),
followed by descriptions of the options for the various images.
An option in an image description will override a global option.
.LP
Comment lines may appear anywhere, and begin with the "#" character.

.SH "GLOBAL OPTIONS"
There are many possible keywords. The description below is
almost literally from user.tex (just slightly abbreviated).
.TP
.BI "backup=" <backup-file>
Specifies the location where a copy of any modified boot sector will be
saved in a file. 'backup=' may specify this location in one of three ways:
a directory where the default backup file 'boot.NNNN' will be created;
a file pathname template to which the '.NNNN' suffix will be added; or
the full file pathname, which must include the correct '.NNNN' suffix.
All RAID installations should use only the first two alternatives, as
multiple backups may be created.  The '.NNNN' suffix is the hexadecimal
representation of the major and minor device numbers of the device or
partition. If this option is not specified, the default name of boot sector
backups is '/boot/boot.NNNN'. If a backup already exists, it will be
preserved, rather than overwritten.  C.f., \fBforce-backup=\fP below.
.TP
.BI "bios-passes-dl=" <option>
The option is indicated as \fIyes\fP, \fIno\fP, or \fIunknown\fP.  If not
specified, a value of "unknown" is assumed, unless additional information
is available to the boot installer. When "no" is specified, it indicates
that the BIOS is known not to pass the current boot device code to the boot
loader in the DL register.  Its only function at this point is experimental,
as certain RAID installations may benefit from knowing that the
BIOS is 100% reliable.  Its use should be considered experimental.
.sp
N.B.:  This option may not be retained in releases beyond 22.5.1, and
may be specified on the command line with the '\-Z' switch:  yes=1, no=0.
.TP
.BI "bitmap=" <bitmap-file>
Specifies use of a 640x480x16 (VGA BIOS) or 640x480x256 (VGA/VESA BIOS)
bitmap file as the background on which a boot
menu is displayed.  May not be used if 'message=' is specified.
Use of this option will select a bitmap-capable boot
loader, unless overridden with "install=" (see below).
.sp
When a bitmap file is specified as a background screen during the boot
process, the color selection and layout of the text which overlays the
graphic image must be specified in one of two ways.  One way, is to use
a bitmap image (*.bmp) file which has had a header written by the
.BI "lilo -E"
command.  If this command is used, then all of the
information specified by the 'bmp-colors', 'bmp-table', and 'bmp-timer'
options is stored in a special LILO header within the bitmap file.
Without this header, the 'bmp-' option values should be
specified in the configuration file; if not, default values are used.
Any use of the 'bmp-' options
within the configuration file overrides the values stored in the
bitmap file header.
.TP
.BI "bmp-colors=" <fg>,<bg>,<sh>,<hfg>,<hbg>,<hsh>
Specifies the decimal values of the colors to be used for the menu display
on a 'bitmap=' background.  The list consists of 6 entries, 3 for normal
text followed by 3 for highlighted text.  The order of each triple is:
foreground color, background color, shadow color.  If background color is
not specified, "transparent" is assumed.  If shadow color is not specified,
then "none" is assumed.  The list entries are separated by commas, with no
spaces.
.TP
.BI "bmp-retain"
Option applies to all 'image=' and 'other=' sections.
(See COMMON OPTIONS, below.)
.TP
.BI "bmp-table=" <x>,<y>,<ncol>,<nrow>,<xsep>,<spill>
Specifies the location and layout of the menu table.  <x>,<y> specify the
starting x- and y-position of the upper left corner of the table in
character coordinates: x in [1..80], y in [1..30]. <ncol> is the number of
columns in the menu (1..5); and <nrow> is the number of rows (entries)
in each column.
If more than one column is specified, then <xsep> is the number of character
columns between the leftmost characters in each column: (18..40), and
<spill> is the number of entries in one column which must be filled before
entries spill into the next column. <spill> must be .le. <nrow>. If pixel
addressing is used, instead of character addressing, then any of <x>, <y>,
or <xsep> may be specified with a 'p' suffix on the decimal value.
.TP
.BI "bmp-timer=" <x>,<y>,<fg>,<bg>,<sh>
Optional specification of the 'timeout='
countdown timer.  <x>,<y> 
specifies the character (or pixel) coordinate of the location of the timer
the same as 'bmp-table='
above; and the color triple specifies the character color attributes
the same as 'bmp-colors=' above, with the exception that the background color
.I must
be specified.  If used to override the timer specification in a bitmap file,
then the form 'bmp-timer = none' is acceptable.  This will disable the timer
display entirely.
.TP
.BI "boot=" <boot-device>
Sets the name of the device (e.g. a hard disk partition) that contains
the boot sector. If this keyword is omitted, the boot sector is read
from (and possibly written to) the device that is currently mounted as root.
.sp
A raid installation is initiated by specifying a RAID1 device as the boot
device; e.g., "boot=/dev/md0".  Note that LILO version 22.0 and later
operate differently from earlier versions with respect to the actual
location of the boot records.
.sp
On newer systems you need an unique ID for the boot device. If the boot
sector should write to a partition you can use its UUID in the same manner
is for the root options.
.sp
If your boot device is a hard disk you need a special ID, which is supported
by udev. You find the right ID in the directory /dev/disks/by-id, i. e.:
.IP
.nf
    boot = /dev/disk/by-id/ata-SAMSUNG_SV1604N_S01FJ10X999999
.fi
.TP
.BI "change-rules"
Defines boot-time changes to partition type numbers (`hiding').
.IP
.nf
change-rules
   reset
   type=DOS12
      normal=1
      hidden=0x11
   type=DOS16_small
      normal=4
      hidden=0x14
   type=DOS16_big
      normal=0x06
      hidden=0x16
.fi
.IP
The above excerpt from a configuration file specifies that all default
.I change-rules
are removed ("reset"), and the change-rules for three partition types
are specified.  Without the \fIreset\fP, the three types specified would
have been added to the existing default change-rules.  Normally, the default
rules are sufficient.  The strings which define the partition types
are used in a
.I change
section (see below), with the suffixes "_normal" or "_hidden" appended.
See section "Partition type change rules" of user.tex for more details.
.TP
.BI "compact"
Tries to merge read requests for adjacent sectors into a single 
read request. This drastically reduces load time and keeps the map file
smaller. Using `compact' is especially recommended when booting
using a map file on a floppy disk. 
.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. See also,
.I vmdefault
below.
.TP
.BI "delay=" <tsecs>
Specifies the number of tenths of a second the boot loader should 
wait before automatically booting a locked command line,
a command line pre-stored by
"lilo \-R", or the default `image=' or `other='.
When `delay' is non-zero, the boot loader will wait for an interrupt for the 
specified interval. If an interrupt is received, or
is already waiting, the \fBboot:\fP
prompt will be be issued, and no automatic boot will take place. The setting
of CAPS LOCK or SCROLL LOCK, or any of the
keys ALT, CTRL, or SHIFT, when held down, are taken as interrupts.

This action is modified by specifying `prompt' (see below).
.TP
.BI "disk=" <device-name>
Defines non-standard parameters for the specified disk.
See section "Disk geometry" of user.tex for details.
For versions of LILO prior to 22.5, the `bios=' parameter
is quite useful for specifying how the BIOS has assigned
device codes to your disks.
For example,
.sp
.nf
       disk=/dev/sda
            bios=0x80
       disk=/dev/hda
            bios=0x81
       disk=/dev/sdb
            inaccessible
.fi
.sp
would say that your SCSI disk is the first BIOS disk (0x80),
that your (primary master) IDE disk is the second BIOS disk (0x81),
and that your second SCSI disk (perhaps a USB device) receives no
device code, and is therefore inaccessible at boot time.
.sp
NOTE: Use of the 'bios=' option is largely obsolete beginning
with LILO version 22.5, as the boot loader now identifies disks
by 32-bit Volume-ID, and defers BIOS device code determination
until boot time.
.sp
Other options include the specification of disk geometry; e.g.,
.sp
.nf
       disk=/dev/fd0
            sectors=18
            heads=2
            cylinders=80
.fi
.sp
probably only useful for floppy disks and loopback devices,
since for hard disks the
.BI lba32
disk addressing option (LILO 21.2) ignores disk geometry.
.sp
(22.5.8) Developers who have implemented a disk driver for a new block storage
device will have to indicate to LILO the maximum number of partitions
on the device.  This is in addition to making all of the necessary
entries for the device in the "/dev" directory (with 'mknod').  The
maximum number of partitions must be one of 63 (like an IDE disk), 31 (uncommon), 15
(like SCSI disks -- most common value), or 7 (like one array controller).
An example specification would be:
.sp
.nf
     disk=/dev/userd0
          max-partitions=15
.fi
.sp
In cases where there is no
kernel partition information available, such as on loopback devices,
the 'disk=' specification may include paritition start information;
viz.,
.sp
.nf
       disk=/dev/loop0
            bios=0x80                   # use this BIOS code
            max-partitions=7            # declare partitionable
            paritition=/dev/loop1
                 start=63               # offset from sector 0
            paritition=/dev/loop2
                 start=102400           # offset from sector 0
.fi
.sp
.TP
.BI "disktab=" <disktab-file>
Specifies the name of the disk parameter table.
The map installer looks for
.I /etc/disktab
if `disktab' is omitted. The use of disktabs is discouraged.
.TP
.BI "el-torito-bootable-CD"
Flag second stage loader to terminate disk emulation when booting
from an El Torito Bootable CD. This option is used by the
\fBmkrescue\fP utility when the "\-\-iso" switch is specified.
.TP
.BI "fix-table"
This allows lilo to adjust 3D addresses in partition tables. Each 
partition entry contains a 3D (cylinder/head/sector) and a linear 
address of the first and the last sector of the partition. If a 
partition is not track-aligned and if certain other operating systems 
(e.g. PC/MS-DOS or OS/2) are using the same disk, they may change the 
3D address. lilo can store its boot sector only on partitions where 
both address types correspond. lilo re-adjusts incorrect 3D start 
addresses if `fix-table' is set.

WARNING: This does not guarantee that other operating systems may 
not attempt to reset the address later. It is also possible that this 
change has other, unexpected side-effects. The correct fix is to 
re-partition the drive with a program that does align partitions to 
tracks. Also, with some disks (e.g. some large EIDE disks with address 
translation enabled), under some circumstances, it may even be 
unavoidable to have conflicting partition table entries.
.TP
.BI "force-backup=" <backup-file>
Operation is identical to \fBbackup=\fP above, except an existing backup
file is unconditionally overwritten if it exists.
.TP
.BI "geometric"
Force disk addressing which is compatible with older versions of LILO. 
Geometric addressing uses cylinder/head/sector addresses, and is limited to
disk cylinders up to 1023.  If inaccessible cylinders are referenced,
diagnostics will be issued at boot-install time, rather than boot-time. 
With a newer BIOS, use of 'lba32' is recommended.
.TP
.BI "ignore-table"
tells lilo to ignore corrupt partition tables. 
.TP
.BI "install=" <user-interface>
Selects the user interface which will be seen at boot time.  One of the
following three options may be specified:  \fBtext\fP, \fBmenu\fP, or
\fBbmp\fP. The traditional LILO interface is `text'; but `menu' is now the
default, unless the configuration file contains the `bitmap='
specification.  The \fItext\fP interface is strictly a command-line
interface as though the console were a dumb terminal.  The \fImenu\fP
interface is a text-based screen of the boot choices, with the option to
enter additional command line parameters.  And the \fIbmp\fP interface is a
menu presented against a graphic screen, specified as a 640x480 BitMaP file
of 16 or 256 colors.  (See the 'lilo \-E' switch for editing options).
.sp
(Prior to LILO version 22.3, `install=' specified the user interface as
a file in the `/boot' directory.)
.TP
.BI "large-memory"
Normally any initial ramdisk (initrd) loaded with a kernel is loaded as
high in memory as possible, but never above 15Mb.  This is due to a BIOS
limitation on older systems.  On newer systems, this option enables using
memory above 15Mb (up to a kernel imposed limit, around 768Mb) for
passing the initrd to the kernel.  The presence of this option merely
indicates that your system does not have the old BIOS limitation.

This switch (or its absence) is not passed to the kernel, and does not
in any way affect the
amount of physical memory which it will use.  (See the
kernel documentation for the kernel command line parameter
"mem=" for limiting the memory used by the kernel.)
.TP
.BI "lba32"
Generate 32-bit Logical Block Addresses instead of cylinder/head/sector 
addresses. If the BIOS supports packet addressing, then packet calls will be
used to access the disk. This allows booting from any partition on disks
with more than 1024 cylinders.
If the BIOS does not support packet addressing, then 'lba32' addresses are
translated to cylinder/head/sector ('geometric'), just as for 'linear'.
All floppy disk
references are retained in C:H:S form.  Use of 'lba32' is recommended on
all post-1998 systems.  Beginning with LILO version 22, 'lba32' is the
default disk addressing scheme.
.TP
.BI "linear"
Generate 24-bit linear sector addresses instead of cylinder/head/sector 
(geometric) addresses. Linear addresses are translated at run time to
geometric addresses, and are limited to cylinders <= 1023. When using
`linear' with large disks,
.I /sbin/lilo
may generate references to inaccessible disk cylinders. 'lba32' avoids
many of these pitfalls with its use of packet addressing, but requires a
recent BIOS (post-1998).  The 'linear' option is considered obsolete,
and its use is strongly discouraged.
.TP
.BI "lock"
Enables automatic recording of boot command lines as the defaults 
for the following boots. This way, lilo "locks" on a choice until it is 
manually overridden.
.TP
.BI "mandatory"
The per-image password option `mandatory' (see below) applies to all images.
.TP
.BI "map=" <map-file>
Specifies the location of the map file. If `map' is omitted, the file
.I /boot/map
is used.

On machines with a pre-1998 BIOS, the EDD bios extensions which are required
to support "lba32" disk sector addressing may not be present. In this case,
the boot-loader will fall back automatically to "geometric" addressing; this
fall back situation, or the specific use of "geometric" or "linear"
addressing, will require the map file to be located within the first 1024
cylinders of the disk drive. This BIOS limitation is not present on
post-1998 systems, most of which support the newer EDD disk BIOS calls.
.TP
.BI "menu-title=" <title-string>
Specifies the title line (up to 37 characters) for the boot menu. This
title replaces the default "LILO Boot Menu" title string. If
.I menu
is not installed as the boot loader (see
.I "install="
option), then this line has no effect.
.TP
.BI "menu-scheme=" <color-scheme>
The default color scheme of the boot menu may be overridden on VGA displays
using this option. (The color scheme of MDA displays is fixed.)
The general
.I color-scheme
string is of the form:
.sp
.nf
     <text>:<highlight>:<border>:<title>
.fi
.sp
where each entry is two characters which specify a
foreground color and a background color. Only the first entry is
required. The default highlight is the reverse of the text color; and the
default border and title colors are the text color.
Colors are specified using the characters \fBkbgcrmyw\fP, for blac\fBK\fP,
\fBB\fPlue, \fBG\fPreen, \fBC\fPyan, \fBR\fPed,
\fBM\fPagenta, \fBY\fPellow, and \fBW\fPhite: upper case for
intense (fg only), lower case for dim.
Legal color-scheme strings would be
.sp
.nf
    menu-scheme=Wm     intense white on magenta
    menu-scheme=wr:bw:wr:Yr    the LILO default
    menu-scheme=Yk:kw    bright yellow on black
.fi
.sp
If
.I "menu"
is not installed as the boot loader, then this line has no effect.
.TP
.BI "message=" <message-file>
specifies a file containing a message that is displayed before
the boot prompt. No message is displayed while waiting 
for a shifting key after printing "LILO ". In the message, the FF
character ([Ctrl L]) clears the local screen. This is undesirable when
the \fImenu\fP boot loader is installed. 
The size of the message 
file is limited to 65535 bytes. The map file has to be rebuilt if the 
message file is changed or moved.  'message=' and 'bitmap=' are mutually
exclusive.
.TP
.BI "nodevcache"
(22.8)
Disables pre-loading of the internal device cache. May be needed for
Linux distributions which use non-standard device naming conventions;
e.g., when the first IDE disk is not `/dev/hda'.
.TP
.BI "nokbdefault=" <name>
(22.7.2)
The named descriptor is taken to be the default boot image 
if no IBM-PC keyboard is 
present. If no serial interface ("serial=") is in use, then any "prompt"
keyword and "timeout" value are bypassed, and default booting occurs as
specified by "delay=".
The keyboard detection codes cannot detect the presence or absence of
a newer USB keyboard.
.TP
.BI "noraid"
Disables the automatic marking of disk volumes which are components of
RAID arrays as \fBinaccessible\fP.  This allows the user to edit the \fBdisk=\fP
/ \fBinaccessible\fP declarations into the configuration file himself.  Without
such declarations, duplicate Volume IDs will be overwritten, leading to
confusing situations at boot-time, and possible failure to boot.  The use
of this keyword is generally not necessary.
.TP
.BI "nowarn"
Disables warnings about possible future dangers.
.TP
.BI "optional"
The per-image option `optional' (see below) applies to all images.
.TP
.BI "password=" <password>
The per-image option `password=...' (see below) applies to all images. This
option may prevent unattended booting, if the default image is `password='
protected at the default level `mandatory', which is a level higher than
`restricted'.
.TP
.BI "prompt"
Automatic booting (see `delay' above) will not take place unless a locked or
pre-stored ("lilo \-R") command line is present. Instead, the boot
loader will issue the 
.I boot:
prompt and wait for user input before proceeding (see
.I timeout
below).
Unattended default image reboots are impossible if `prompt' is set
and `timeout' is not, or the default image is password protected at a higher
level than `restricted'.
.TP
.BI "raid-extra-boot=" <option>
This option only has meaning for RAID1 installations.
The <option> may be specified as \fInone\fP, \fIauto\fP, \fImbr\fP,
\fImbr-only\fP,
or a comma-separated list of devices; e.g., "/dev/hda,/dev/hdc6".  Starting
with LILO version 22.0, the boot record is normally written to the first
sector of the RAID1 partition.  On PARALLEL raid sets, no other boot records
are needed.  The
default action is \fIauto\fP, meaning, automatically generate auxiliary boot
records as needed on SKEWED raid sets.  \fInone\fP means
suppress generation of all auxiliary boot records.
\fImbr-only\fP suppresses generation of a boot record on the raid device,
and forces compatibility with versions of LILO earlier than version 22.0
by writing boot records to all Master Boot Records (MBRs) of all disks which
have partitions in the raid set. \fImbr\fP is like \fImbr-only\fP except the
boot record on the RAID partition is not suppressed.
Use of an explicit list of devices, forces writing of auxiliary boot records
only on those devices enumerated, in addition to the boot record on the RAID1
device. Since the version 22 RAID1 codes will never automatically write a boot
record on the MBR of device 0x80, if such a boot record is desired, this is
one way to have it written. Use of \fImbr\fP is the other way to force
writing to the MBR of device 0x80.
.TP
.BI "restricted"
The per-image password option `restricted' (see below) applies to all images.
.TP
.BI "serial=" <parameters>
enables control from a serial line. The specified serial port is
initialized and the boot loader is accepting input from it and from 
the PC's keyboard. Sending a break on the serial line corresponds to 
pressing a shift key on the console in order to get the boot loader's
attention. 
All boot images should be password-protected if the serial access is 
less secure than access to the console, e.g. if the line is connected 
to a modem. The parameter string has the following syntax:
.sp
.nf
    <port>[,<bps>[<parity>[<bits>]]]
.fi
.sp
<port>:  the number of the serial port, zero-based. 0 corresponds to
COM1 alias /dev/ttyS0, etc. All four ports can be used (if present).
.sp
<bps>:  the baud rate of the serial port. The following baud rates are 
supported: 110, 150, 300, 600, 1200, 2400(default), 4800, 9600, plus the 
extended rates 19200, 38400, and 57600(56000).  115200 is allowed, but may
not work with all COMx port hardware.
.sp
<parity>:  the parity used on the serial line. The boot loader ignores input 
parity and strips the 8th bit. The following (upper or lower case) 
characters are used to describe the parity:  "n" for no parity, "e" 
for even parity and "o" for odd parity.
.sp
<bits>:  the number of bits in a character. Only 7 and 8 bits are 
supported. Default is 8 if parity is "none", 7 if parity is "even" 
or "odd". 
.sp
If `serial' is set, the value of `delay' is automatically raised to 20.
.sp
Example: "serial=0,2400n8" initializes COM1 with the default parameters.
.TP
.BI "single-key"
This option specifies that boot images or 'other's are to be selected and
launched with a single keystroke.  Selection is based upon the first
character of each name, which must be unique.  This option should not be
used with the menu or bitmap user interface ("install=").
.TP
.BI "static-BIOS-codes"
Causes the operation of the boot installer and boot loader to bypass the
use of Volume-ID information, and to revert to a mode of operation of
versions of LILO from 22.4 backward.  With Volume-ID booting (22.5 and later),
the BIOS codes
of disks are determined at boot time, not install time; hence they may
be switched around, either by adding or removing disk(s) from the hardware
configuration, or by using a BIOS menu to select the boot device.
.sp
With the use of
this option, BIOS codes of disks MUST be correctly specified at install
time; either guessed correctly by LILO (which often fails on
mixed IDE/SCSI systems), or explicitly specified with 'disk=/dev/XXX
bios=0xYY' statements.  The use of this option precludes
any activity which may switch around the BIOS codes assigned to particular
disk devices, as noted above.
.sp
In general, this option should
never be used, except as a bug workaround.
.TP
.BI "suppress-boot-time-BIOS-data"
This global option suppresses the boot-time real mode collection of BIOS data
on systems which hang on certain BIOS calls.  It is equivalent to using the
boot-time switch 'nobd'.
.sp
This option defeats the disk volume recognition and BIOS device code
detection features of LILO on systems with more than one disk. Thus the use
of this option will produce a strong cautionary message,
which cannot be suppressed.
.TP
.BI "timeout=" <tsecs>
sets a timeout (in tenths of a second) for keyboard input at the 
.I boot:
prompt.  "timeout" only has meaning if "prompt" is mentioned.
If no key is pressed for the specified time, the default image is 
automatically booted. The default timeout is infinite.
.TP
.BI "unattended"
(22.6) Alters the operation of the "timeout" parameter in a manner which
is useful on
noisy serial lines.  Each typed (or noise) character restarts the "timeout"
timer and a timeout will always boot the default descriptor, even if noise
characters have appeared on the input line.
.TP
.BI "verbose=" <number>
Turns on lots of progress reporting. Higher numbers give more verbose
output. If  \-v  is additionally specified on the lilo command line,
the level is increased accordingly. The maximum verbosity level is 5.
.TP
.BI "vmdefault=" <name>
The named boot image is used as the default boot if booting in "virtual"
mode with a virtual monitor, such as VMware(tm).  Thus a real mode boot and
a virtual mode boot can be made to have different default boot images.
.br

.LP
Additionally, the kernel configuration parameters
.BR append ", " ramdisk ", " read-only ", " read-write ", " root
and
.B vga
can be set in the global options section. They are used as defaults
if they aren't specified in the configuration sections of the
respective kernel images.

.SH "PER-IMAGE SECTION"
A per-image section starts with either a line
.sp
.nf
    \fBimage=\fP\fI<pathname>\fP
.fi
.sp
to indicate a file or device containing the boot image of a Linux
kernel, or a line
.sp
.nf
    \fBother=\fP\fI<device>\fP
.fi
.sp
to indicate an arbitrary system to boot.
.LP

In the former case, if an \fBimage\fP line specifies booting
from a device, then one has to indicate the range of sectors to be mapped
using
.sp
.nf
    \fBrange=\fP\fI<start>-<end>\fP
    \fBrange=\fP\fI<start>+<nsec>\fP
    \fBrange=\fP\fI<sector>\fP
.fi
.LP
In the third case, 'nsec=1' is assumed.

.SH "KERNEL OPTIONS (image=)"
If the booted image is a Linux kernel, then one may pass
command line parameters to this kernel.
.TP
.BI "addappend=" <string>
(22.6) The kernel parameters from the specified string, are concatenated to the
parameter(s) from an
.B "append="
specification (see below).
The string must be enclosed within double quotes.  Usually, the previous
.B "append="
will specify parameters common to all kernels by appearing in the top,
or global, section of the configuration file and
.B "addappend="
will be used to add local parameter(s) to an individual image.
Addappend= may be used only once per "image=" section.
.TP
.BI "append=" <string>
Appends the options specified to the parameter line passed to the kernel.
This is typically used to specify hardware parameters that can't be
entirely auto-detected or for which probing may be dangerous. Multiple
kernel parameters are separated by a blank space, and the string must be
enclosed in double quotes.  A local append= appearing withing an image=
section overrides any
global append= appearing in the top section of the configuration file.
Append= may be used only once per "image="
section. To concatenate parameter strings, use "addappend=". Example:
.sp
.nf
     append="mem=96M hd=576,64,32 console=ttyS1,9600"
.fi
.sp
.TP
.BI "initrd=" <name>
Specifies the initial ramdisk image to be loaded with the kernel.  The
image will contain modules needed at boot time, such as network and scsi
drivers. See man pages for \fImkinitrd(8)\fP.
.TP
.BI "literal=" <string>
Like `append', but removes all other options (e.g. setting of the root
device). 'literal' overrides all 'append' and 'addappend' options.
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 (e.g., "4096k") 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.
It may be specified as a global option.
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.
It may be specified as a global option.
.TP
.BI "root=" <root-device>
This specifies the device that should be mounted as root. 
It may be specified as a global option.
If the special name
.B current
is used, the root device is set to the device on which the root file
system is currently mounted. If the root has been changed with  \-r ,
the respective device is used. If the variable `root' is omitted,
the root device setting contained in the kernel image is used.
(And that is set at compile time using the ROOT_DEV variable in
the kernel Makefile, and can later be changed with the rdev(8) program.)
.sp
The root filesystem may also be specified by a
.B LABEL=
or
.B UUID=
directive, as in '/etc/fstab'.  In this case, the argument to
.I root=
must be enclosed in quotation marks, to avoid a syntax error on the second
equal sign, e.g.:
.sp
.nf
     root="LABEL=MyDisk"
     root="UUID=5472fd8e-9089-4256-bcaa-ceab4f01a439"
.fi
.sp
Note:  The command line
.I root=
parameter passed to the kernel will be: 'root=LABEL=MyDisk'; i.e., without
the quotation marks. If the
.I root=
parameter is passed from the boot time
.B boot:
prompt, no quotes are used.  The quotes are only there to satisfy the
requirements of the boot-installer parser, which treats an equal sign as
an operator.  The kernel command line parser is very much simpler, and
must not see any quotation marks.  Simply stated, only use the quotation
marks within
.IR /etc/lilo.conf .
.TP
.BI "vga=" <mode>
This specifies the VGA text mode that should be selected when 
booting.
It may be specified as a global option.
The following values are recognized (case is ignored): 
.sp
.BR normal :
select normal 80x25 text mode. 
.sp
.BR extended " (or " ext ):
select 80x50 text mode.
.sp
.BR ask :
stop and ask for user input (at boot time).
.sp
<number>: use the corresponding text mode. A list of available modes 
can be obtained by booting with
.I vga=ask
and pressing [Enter]. 
.sp
If this variable is omitted, the VGA mode setting contained in the 
kernel image is used. (And that is set at compile time using the
SVGA_MODE variable in the kernel Makefile, and can later be changed with
the rdev(8) program.)

.SH "ALTERNATE SYSTEM (other=)"
.LP
Used to load systems other than Linux. The `other = <device>' specifies
the boot sector of an alternate system contained on a device or disk
partition; e.g., DOS on, say, `/dev/hda2', or a floppy on `/dev/fd0'.
In the case of booting another system there are these options:
.TP
.BI "loader=" <chain-loader>
This specifies the chain loader that should be used.  It may also be
specified as a global option.
By default
.I chain
is used.  This chain loader passes partition and drive information in the
boot sector it loads only to DOS on FAT12 or FAT16, Windows on FAT16 or
FAT32, or OS/2 on FAT16 or HPFS.
The alternate chain loader,
.I os2_d
passes partition and drive information unconditionally, and uses a format
suitable for OS/2 and DOS (see 
.I table=<letter>
below).
.TP
.BI "table=" <device>
This specifies the device that contains the partition table. 
The boot loader will pass default partition information to the booted
operating system if this variable is omitted. (Some operating systems
have other means to determine from which partition they have been booted.
E.g., MS-DOS usually stores the geometry of the boot disk or partition
in its boot sector.)
Note that /sbin/lilo must be re-run if a partition table mapped referenced
with `table' is modified.
.TP
.BI "table=" <drive-letter>
This is a special case for the
.I os2_d
chain loader.  It specifies the DOS drive letter for the partition
that will be booted.  This is
.I mandatory
when booting OS/2 installed on
an extended partition.  The drive letter may be specified with or without a
trailing colon.
.TP
.BI "change"
This keyword starts a section which describes how primary partition IDs are
changed, and how primary partitions are activated and deactivated.  If
.B change
is omitted, change rules are generated as though the 
.I "automatic"
keyword were specified.  The keyword
.B change
alone, without any rules following, will suppress automatic change-rules.
For example,
.IP
.nf
   other=/dev/hda2
      label=dos
      table=/dev/hda
      change
        automatic
        partition=/dev/hda1
           set=DOS12_hidden
           deactivate
        partition=/dev/hda2
           set=DOS16_big_normal
           activate
.fi
.IP
specifies that when primary partition /dev/hda2 is booted, automatic
change-rules will be in effect; plus, partition 1, a DOS12 partition, will
be set hidden, and deactivated.  In addition, partition 2, will be set
normal, and activated.  Activation sets the boot-flag in the partition
table.  The 
.I automatic
keyword may conflict with default change rules, so the
.I set=
lines above may be redundant.
.TP
.BI "boot-as=" "<bios>"
This option (LILO version 22.5.1) indicates the BIOS device code which must
be assigned to the specified drive in order for the "other=" operating
system to boot.  If the chain loader detects that another BIOS device code
is assigned to this disk, then it will dynamically swap the assigned device
code with the specified device code.
.sp
This option is easier to specify than "map-drive=" and more general than
"master-boot" in that any device code may be specified.  Unlike
"map-drive=", the determination whether to swap device codes is made at boot
time, not install time.  This is advantageous on systems where the BIOS
presents a boot menu of devices, and will map disks to devices in different
ways, depending upon the BIOS boot selection.
.sp
This option may be specified as a global option, in which case it applies to
all "other=" sections unless overridden with a specific "master-boot" option.
If one of "boot-as=" or "master-boot" is specified as a global option, it is
better to specify "master-boot" as the global option, as it will not
interfere with floppy disk BIOS device codes; "boot-as=" is then used as a
local option to override "master-boot" as necessary.
.TP
.BI "master-boot"
This flag (LILO version 22.5) indicates a DOS/Windows/OS2 or other
system which will only boot from BIOS device 0x80, the "C:" drive, or BIOS
device 0, the A: drive. When this
flag is specified, if this drive is not assigned device code 0x80 or 0 by the
BIOS, then the chain loader will dynamically swap the device code actually
assigned with device code 0x80 or 0 to make this drive appear
to be the first hard or floppy drive, "C:" or "A:".
.sp
This flag is easier to use than "map-drive=" (see below), and is preferred,
if simple forcing of device code 0x80 is all that is required. It is also
more general, in that the necessity to swap BIOS device codes is determined
dynamically at boot-time, not at boot install-time, as with "map-drive=". 
It is slightly more powerful than "boot-as=", in that the device code which
is assigned, 0 or 0x80, is determined dynamically.
.sp
This option may be specified as a global option, in which case it applies to
all "other=" sections unless overridden with a specific "boot-as=" option.
.TP
.BI "map-drive=" <num>
Maps BIOS calls for the specified drive to the device code specified on the
next line as \fBto=\fP<num>.  This mapping is useful for booting operating
systems, such as DOS, from the second hard drive.  The following, swaps the
C: and D: drives,
.sp
.nf
   map-drive=0x80
      to=0x81
   map-drive=0x81
      to=0x80
.fi
.sp
This option is largely
rendered obsolete by "boot-as=", introduced with LILO version 22.5.
.TP
.BI "unsafe"
Do not access the boot sector at map creation time. This disables 
some sanity checks, including a partition table check. If the boot 
sector is on a fixed-format floppy disk device, using UNSAFE avoids the 
need to put a readable disk into the drive when running the map 
installer. If the boot sector is on a hard drive, the BIOS device code
of the drive will have to be specified explicitly with "disk=/dev/XXXX
bios=0x8X inaccessible" in the configuration file.
`unsafe' and `table' (explicit or implicit) are mutually incompatible. 

.SH "COMMON DESCRIPTOR OPTIONS (image= & other=)"
.LP
In both the
.BR image= " and " other=
cases, the following options apply.
.TP
.BI "bypass"
No password is required to boot this image. Used to indicate that the global
password does not apply to this `image=' or `other='.  See 'password=' below.
.TP
.BI "label=" <name>
The boot loader 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 "bmp-retain"
The bitmap graphic (install=bmp) is retained when control is passed to the
loaded kernel image, or other= bootloader; i.e., the screen is not
blanked to alphanumeric mode before starting the kernel.  This feature is
considered EXPERIMENTAL, for those users working with startup splash
screens.
.TP
.BI "fallback=" <command-line>
Specifies a string that is stored as the default 
command line if the current image is booted. This is useful when 
experimenting with kernels which may crash before allowing interaction 
with the system. If using the
.BI fallback
option, the next reboot (e.g. 
triggered by a manual reset or by a watchdog timer) will load a 
different (supposedly stable) kernel. The command line stored by the fallback 
mechanism is cleared by removing or changing the default command line 
with the
.IR "-R"
option, which should be a part of the boot startup scripts.
.TP
.BI "lock"
(See above.)
.TP
.BI "optional"
Omit the image if it is not available at map creation time.
It may be specified as a global option.
This is useful to specify test kernels that are not always present.
.TP
.BI "password=" <password>
Protect the `image=' or `other=' with a password (or passphrase).
It may be specified as a global option.
The interpretation of the `password=' setting is modified by the words
`mandatory', `restricted', and `bypass' (see below).
.br
The password may be specified in the config-file (less secure) or entered
at the time the boot loader is installed. To request interactive entry of
the password, it should be specified: \fBpassword=""\fP.
Passwords entered interactively are not required to be entered again if the
boot installer is re-run. They are cached, in hashed form, in a companion
file to the config-file, default name: \fB/etc/lilo.conf.crc\fP. If the 
config-file is updated, a warning message
will be issued telling you to re-run \fIlilo \-p\fP to force re-creation of the
password cache file.
.TP
.BI "mandatory"
A password is required to boot this image. This is the default. May be used
on a single `image=' or `other=' to override a different global setting.
.TP
.BI "nokbdisable"
(22.7.2)
The specified descriptor is not bootable if the IBM-PC keyboard is not present.
This option is really only useful if the "serial=" boot terminal is in use.
With no keyboard (and no serial terminal) attached, selecting a boot descriptor 
other than the default is impossible.
See
.I nokbdefault
above.
.TP
.BI "restricted"
A password is only required to boot the image if kernel parameters
are specified on the command line (e.g. 'single').  May be used
on a single `image=' or `other=' to override a different global setting.
.TP
.BI "vmwarn"
If booting under a virtual monitor such as VMware(tm), the image with this
label will cause a cautionary warning to be issued at boot time, and user
intervention will be required to continue or to abort the boot process.
.TP
.BI "vmdisable"
If booting under a virtual monitor, the image with this label will not be
displayed as a boot option.  The image is only bootable in real mode.  See
.I vmdefault
above.

.LP

.SH "SEE ALSO"
lilo(8), mkinitrd(8), mknod(1), mkrescue(8), rdev(8).