Making a grub boot floppy

Having spent ages trying different methods of making a boot floppy and not having much success I finally found a method and just wish to pass it on.

Please note that I have only tried this with Debian and it may not work with other Linux distro's. The commands used apply specifically to Debian and may differ in other distro's.

Standard Disclaimer; I take no responsibility for the results achieved from the following!

First take a known good floppy and format it. Using a shell console or from the command line as root do

fdformat /dev/fd0 (or the number of your floppy drive)

Assuming that you have a correctly configured grub on your system we can now write it to the floppy by now doing;

grub-install /dev/fd0

Check that the floppy works by rebooting from it. If the boot floppy works then it is job done.

Creating a boot cd from the boot floppy

If you are thinking, why make a boot cd when you already have a floppy then the reason is that floppies don't tend to be very reliable media in my experience and just when you really need it, it doesn't work. A cd on the other hand, if stored properly is very reliable. So here's how to make a boot cd from the floppy

Firstly create a temporary directory in your home directory

mkdir /home/your_user_name/tmp

Now we need to create an image of the floppy in this directory, so do;

dd if=/dev/fd0 of=/home/your_user_name/tmp/boot.img bs=10k count=144

Now we have an image of the floppy disk we can create a boot iso to burn to a cd. If you want to know the technical background then here is a reference. Here are the mechanics. Again from a consol do;

mkisofs -r -b /home/your_user_name/tmp/boot.img -c -o /home/your_user_name/tmp/bootcd.iso .

Note the "." on the end of this line it is important

You can now burn the iso file to a cd and you should have a boot cd as well to keep in a safe place

I hope you find the information useful and enjoy the site. If you have any suggestions or comments or would like to contact me then please e-mail me
Rob Oats
July 2004