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Date: Tue, 3 Feb 2004 00:41:35 -0800 (PST)
From: Dan Strick <strick@covad.net>
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To: freebsd-questions@FreeBSD.ORG
cc: dan@mist.nodomain
Subject: Re: MBR
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On Tue, 27 Jan 2004 16:49:02 +0100 (?), Namik Dala wrote:
>>
> On Tue, Jan 27, 2004 at 09:10:51AM -0600, Brian H wrote:
> > Currently I have the BSD boot loader running in my MBR, but since I only
> > have BSD on my system I would like to replace it with the standard MBR. Is
> > there a way with unix to safely reset the MBR?
>
> This
>
>   dev=/dev/ad0 # change this
>   dd if=$dev of=/boot/mbr.backup bs=512 count=1
>   dd if=/boot/mbr of=$dev bs=512 count=1
>
> should to the trick.
>>

I suspect this would erase the MBR partition (aka "slice") table.

Use the "fdisk" command "-B" option to install the bootstrap program
from /boot/mbr.  Be sure to set the desired "active" partition so that
the bootstrap program knows which partition to boot.

Dan Strick
strick@covad.net