Backing Up the MBR

BACKING UP THE MBR

Here is a clever trick that John Locke sent us for backing up and restoring the MBR . . . :

QUOTE (John @ Mail 2004)

Just another note about restoring the boot loader for dual boot systems,
after Windows messes it up. In Linux, the "dd" command can read and
write to/from raw disks and files. If you have a floppy drive, creating
a boot disk is as simple as putting a floppy in the drive and typing
this:

$ su
<type password>
# dd if=/dev/hda of=/dev/fd0 bs=512 count=1

This makes an exact copy of the MBR of the first hard drive, copying it
to a floppy disk. You can boot directly from this floppy, and see your
old boot menu. You can restore it by switching the "if=" and "of="
(input file, output file) parameters.

If you don't have a floppy drive, you can back it up to a file with
this:

# dd if=/dev/hda of=/home/john/boot.mbr bs=512 count=1

Then you can boot into a CD-ROM distribution such as Knoppix, or often
use your Linux distribution's installation CD to boot into rescue mode,
and restore it with:

$ su
# dd if=/mnt/hda5/john/boot.mbr of=/dev/hda bs=512 count=1

(you'll need to find and mount the partition containing the directory
where you backed up the MBR for the "if" parameter--this is an example).

Cheers,
--
John Locke

Thanks John, nice one !

Bruno

PS: Also, Striker shows us a way to write lilo to floppy:

QUOTE (Striker @ Forum 2004)

# /sbin/lilo -b /dev/fd0