LILO Mini-HOWTO
This file describes some typical LILO installations.
It's intended as a supplement to the LILO User's Guide.
I think examples are informative even if your setup isn't much like mine.
I hope this saves you trouble.
Cameron Spitzer, cls@truffula.sj.ca.us
Example 1:
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I have two IDE drives, and a SCSI drive. The SCSI drive can't be
seen from BIOS.
The Linux Loader, LILO, uses BIOS calls and can only see drives that
BIOS can see. My stupid AMI BIOS will only boot from "A:" or "C:"
My root file system is on a partition on the SCSI drive.
The solution:
Store the kernel, map file, and chain loader in a Linux partition on
the first IDE. Notice that it is not necessary to keep your kernel on
your root partition.
The second partition on my first IDE (/dev/hda2) is mounted on /u2.
Here is the /etc/lilo.conf file I used.
# Install LILO's boot record as Master Boot Record
# on the first IDE.
#
boot = /dev/hda
# /sbin/lilo (the installer) copies the LILO boot record from the
# following file to the MBR location.
install = /u2/etc/lilo/boot.b
#
# I wrote a verbose boot menu. LILO finds it here.
message = /u2/etc/lilo/message
# The installer will build the following file.
# It tells the boot-loader where the blocks of the kernels are.
map = /u2/etc/lilo/map
compact
prompt
# Wait 10 seconds, then boot the 1.2.1 kernel by default.
timeout = 100
# The kernel is stored where BIOS can see it by doing this:
# cp -p /usr/src/linux/arch/i386/boot/zImage /u2/z1.2.1
image = /u2/z1.2.1
label = 1.2.1
# LILO tells the kernel to mount the first SCSI partition as root.
# BIOS does not have to be able to see it.
root = /dev/sda1
# This partition will be checked and remounted by /etc/rc.d/rc.S
read-only
# The same kernel can be told to mount a different partition as
# root instead. I have an emergency root setup on /u2.
image = /u2/z1.2.1
label = 1.2.1-hda2
root = /dev/hda2
read-only
# I kept an old Slackware kernel lying around in case I built a
# kernel that doesn't work. I actually needed this once.
image = /u2/z1.0.9
label = 1.0.9
root = /dev/sda1
read-only
# My DR-DOS 6 partition.
other = /dev/hda1
loader=/u2/etc/lilo/chain.b
label = dos
alias = m
Example 2:
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The system in my office has a 1GB IDE drive.
The BIOS can only see the first 504 MB of the IDE.
(Where MB means 2**10 bytes, not 10**6 bytes.)
So I have MS-DOS on a 350 MB partition /dev/hda1 and my
Linux root on a 120 MB partition /dev/hda2.
MS-DOS was unable to install itself correctly when the drive was
fresh. Novell DOS 7 had the same problem.
Luckily for me, "Options by IBM" forgot to put the "OnTrack"
diskette in the box with the drive. The drive was supposed to
come with a product called "OnTrack Disk Manager." If you only
have MSDOS, I guess you have to use it.
So I made a partition table with Linux' fdisk.
MSDOS-6.2 refused to install itself in /dev/hda1. It said
something like
'this release of MS-DOS is for new installations.
Your computer already has MS-DOS
[which was wrong, the drive was fresh]
so you need to get an�upgrade release from your dealer.'
What a crock! So I ran Linux' fdisk again and deleted partition 1
from the table. This satisfied MS-DOS 6.2 which proceeded to
create the exact same partition 1 I had just deleted and installed
itself. MS-DOS 6.2 wrote its Master Boot Record on the drive, but
it couldn't boot.
Luckily I had a Slackware kernel on floppy (made by the Slackware
installation program "setup"), so I booted Linux and wrote LILO
over MS-DOS' broken MBR. This works.
Here is the /etc/lilo.conf file I used:
boot = /dev/hda
map = /lilo-map
delay = 100
ramdisk = 0 # Turns off the ramdisk in the Slackware kernel
timeout = 100
prompt
disk = /dev/hda # BIOS only sees first 500 MB.
bios=0x80 # specifies the first IDE.
sectors = 63 # get these numbers from your drive's documentation.
heads = 16
cylinders = 2100
image = /vmlinuz
append = "hd=2100,16,63" # This may be redundant.
root = /dev/hda2
label = linux
read-only
vga = extended
other = /dev/hda1
label = msdos
table = /dev/hda
loader = /boot/chain.b
## end
After I installed these systems, I verified that the partition containing
the zImage, boot.b, map, chain.b, and message files can use an msdos
file system, as long as it is not "stackered" or "doublespaced."
So I could have made the DOS partition on /dev/hda1 500 MB.
I have also learned that "OnTrack" would have written a partition table
starting a few dozen bytes into the drive, instead of at the beginning,
and it is possible to hack the Linux IDE driver to work around this
problem. But installing would have been impossible with the precompiled
Slackware kernel. Eventually, IBM sent me an "OnTrack" diskette.
I called OnTrack's technical support. They told me Linux is broken
because Linux doesn't use BIOS. I gave their diskette away.
Example 3:
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Next, I installed Windows-95 on my office system. It blew away my nice
LILO MBR, but it left my Linux partitions alone. Kernels take a long
time to load from floppy, so I made a floppy with a working LILO setup
on it, which could boot my kernel from the IDE.
I made the lilo floppy like so:
fdformat /dev/fd0H1440 # lay tracks on virgin diskette
mkfs /dev/fd0 1440 # make file system of type minix
mkdir /3 # make a place to mount it
mount /dev/fd0 /3
cp -p /boot/chain.b /3 # copy the chain loader over
lilo -C /etc/lilo.flop # install LILO and the map on the diskette.
umount /3
Notice that the diskette MUST BE MOUNTED WHEN YOU RUN THE INSTALLER
so that lilo can write its map file properly.
This file is /etc/lilo.flop. It's almost the same as the last one:
# Makes a floppy that can boot kernels from HD.
boot = /dev/fd0
map = /3/lilo-map
delay = 100
ramdisk = 0 # Turns off the ramdisk in the Slackware kernel
timeout = 100
prompt
disk = /dev/hda # 1 GB IDE, BIOS only sees first 500 MB.
bios=0x80
sectors = 63
heads = 16
cylinders = 2100
image = /vmlinuz
append = "hd=2100,16,63"
root = /dev/hda2
label = linux
read-only
vga = extended
other = /dev/hda1
label = msdos
table = /dev/hda
loader = /3/chain.b
## end
Finally, I needed MS-DOS 6.2 on my office system, but I didn't
want to touch the first drive. I added a SCSI controller and
drive, made an msdos file system on it with Linux' mkdosfs, and
Windows-95 sees it as "D:". But of course MSDOS will not boot
off of D:. This is not a problem when you have LILO. I added
other = /dev/sda1
label = d6.2
table = /dev/sda
loader = /boot/any_d.b
to the lilo.conf in Example 2. MSDOS-6.2 runs, and it thinks
it is on C: and Windows-95 is on D:.