MBR

[Ed Wilts]

On Wed, May 18, 2005 at 07:18:40AM -0400, Burke, Thomas G. wrote:
> doing an fdisk /mbr shouldn't hurt you physically, in fact it is quite
> useful for when the master boot record gets corrupted.  Unfortunately,
> it wipes out lilo in the boot record, so you can't boot without a
> disk.

It wipes out both grub and lilo but your first sentence is also true -
it doesn't hurt you physically.  I did an fdisk /mbr when I was
studying for my RHCE to see how long it would take me to recover (not
long).  After you've wiped out the mbr, boot into rescue mode and do a
grub-install /dev/hda and you're done.

> If you have a disk that will allow you to boot to the normal OS & have
> everything mounted, do the following:

> 1) fdisk /mbr

You can do this from a Windows boot floppy.

> 2) reboot into single user mode

You can't boot into single user mode after wiping out the mbr - it's the
master BOOT record that you've just destroyed.

-- 
Ed Wilts, RHCE
Mounds View, MN, USA
mailto:ewilts at ewilts.org
Member #1, Red Hat Community Ambassador Program