Making Boot Diskettes

All diskettes are not created equal. If you don't know the difference, read the explanation.

1. Kernel disk:

dd if=/boot/vmlinuz of=/dev/fd0

Make sure you put the right argument after 'of'. This is the 'output file', and you don't want to write over anything important! The diskette should be formatted but does not require any kind of file system present. The name and location of your Linux kernel may differ from /boot/vmlinuz shown above, so substitute as necessary.

2. Boot Floppy

The boot= line in lilo.conf determines where LILO is written to. So, find your lilo.conf file (should be in /etc), and edit it (make a backup copy first, if you like). One of the first lines will say:

boot=/dev/hda

If you have a boot manager and boot lilo from a partition you will see hda1 instead. And of course your partition is likely to be other than hda1. Now comment out that line and add a new one so that it reads:

# boot=/dev/hda boot=/dev/fd0

and save the file. Naturally, you can write to a second floppy by substituting /dev/fd1, and so on. Now put the diskette in, execute /sbin/lilo, and voila! The LILO boot is written to the diskette instead of the hard drive. Everything else is left the same. All of the other files are still read from your hard drive at bootup. Remember this disk only works with your computer! (And remember to change lilo.conf back!)

3. Emergency Boot

In this section we will learn how to make a diskette that will start Linux and mount the root file system from your hard disk. It can be used on other computers by specifying the partition where the root file system is found.

There's more than one way to do this.

The approach taken is not one I've seen elswhere. It may appear somewhat unusual but I believe that it has some advantages:

It should work reliably despite configuration differences in your machine.
It will help you along which makes it easier to understand and remember.
It will introduce you to some error messages and troubleshooting skills.
It will demonstrate and teach you the necessary components of a LILO-booted system.

On the other hand, I'm new at this and I could be all wet. But I've actually done this and it does work!

What we will do is create a lilo.conf file on the diskette and then obtain the necessary files to make it work.

Start with a blank formatted disk. (how).

Copy or create a lilo.conf

- - - - - - - - - - - - basically just take 'em to liloflop.htm . . .

`lilo`	`(lilo.conf not found)`
`liloetc/conf.lilo`	`(lilo.conf not found)`
`lilo /mnt/floppy/etc/lilo.conf`	`(lilo.conf not found)`
`cd /mnt/floppy/etc`
`lilo`	`(lilo.conf not found)`
`cd /mnt/floppy`
`cp etc/lilo.conf /etc`
`lilo`	`(boot/message not found)`
`cp boot/message /boot lilo`	`(no kernel to load)`
`cp vmlinuz-2.0.34-0.6 /`
`lilo`	`(initrd.img not found)`
`cp initrd.img /`
`lilo`	`(added linux added rescue)`

4. Rescue Disk or Repair Disk:

This procedure is currently beyond the scope of this site (in other words, my knowledge) for the following reasons:

I have not yet learned how to create ramdisks.
Creating a self-contained Linux system requires many things like a /dev tree, an init program, startup command files, getty, daemons, shells, etc.
There are several kinds of rescue and repair disks, so there would have to be a lot of instructions.

If you want one of these disks you can make one from your Linux distribution CD. Look for the rawrite program and the kernel images. There should be some files in those directories that explain how you do this.

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