HOWTO: Boot a DOS floppy-image without a floppy drive

[Jussi Kukkonen]

The floppy drive is an almost dead technology by now. Unfortunately one may need to boot from a floppy image neverteless -- in my case I had to run a BIOS update utlity for my Matrox G450 graphics card. Here's how I did it without a floppy drive.
From step 2 onwards you'll have to be root (or use sudo) pretty much all the time. The example commands are for Ubuntu 6.06 and should work on Debian derivatives.

1. Download the files you want to put on the floppy. (I needed setup_g258_2.exe from Matrox), open the archive if needed:
   

   wget ftp://ftp.matrox.com/pub/mga/archive/bios/2006/setup_g258_2.exe
   unzip setup_g258_2.exe

2. Install syslinux (dos floppy bootloader):
   

   aptitude install syslinux

3. Create a directory for DOS stuff and copy the bootloader and the disk image there. memdisk may be elsewhere on your system, and the image will be wherever you copied/unzipped it to.
   

   mkdir /boot/dos
   cp /usr/lib/syslinux/memdisk /boot/dos
   cp ~/setup_g258_2/mini.ima /boot/dos

4. Create a mount point and mount the floppy image.
   

   mkdir /media/floppy
   mount -t msdos -o loop /boot/dos/mini.ima /media/floppy

5. Delete unnecessary files (if your actual files need all the space a floppy has). Copy your files to "floppy":
   

   rm ~/floppy/autoexec.bat /media/floppy/dl8.exe
   cp ~/setup_g258_2/*.bin ~/setup_g258_2/progbios.exe /media/floppy/
   umount /media/floppy

6. Add a boot option for the floppy image. With grub on Ubuntu this means adding something like this into /boot/grub/menu.lst (after AUTOMAGIC KERNELS LIST, of course):
   

   title	Matrox BIOS update (DOS)
   root	(hd0,1)
   kernel	/boot/dos/memdisk
   initrd	/boot/dos/mini.ima
   boot

7. Reboot, choose the "Matrox BIOS update" -boot option. Run whatever programs you need to run, this is for the Matrox BIOS updater:
   

   progbios -i auto -q

This howto originally lived in the Matrox forums. Unfortunately the tactless bastards closed the forum down without any warning (this content is rescued from Google cache). I hope this is useful for someone. Corrections are welcome.

sources:
http://gentoo-wiki.com/TIP_Boot_Flop...ppy_using_GRUB
http://forum.matrox.com/mga/viewtopic.php?t=4379 (not available, see above)

[chris_x1]

very clever, thanks

[guschdaevle]

that's what i am looking for
thanx for rescuing this howto

guschdaevle

[patrickjlbyrne]

I found that '-o mount' does not work in Ubuntu 9.04.

Instead I found via:

http://en.wikipedia.org/wiki/Loop_device

that doing (eg):

losetup /dev/loop0 example.img
mount /dev/loop0 /home/you/dir

works instead.