Dangerous file system / disk problem

[Dan Strick]

On Sun, 6 Jun 2004 12:13:17 +0100, Ben Paley wrote:
>>
> I wanted to have FreeBSD on my first drive and Win98 on the second, but
> of course windows doesn't like being on the second disk, and began
> "preparing" my first drive which already had FreeBSD on it! Well, I
> swapped the drives over, put W98 on the first one, they both boot fine
> and I didn't lose any data.
>
> BUT - Windows now sees my BSD disk (which has never happened before) and
> keeps offering to format it for me. Partition Magic gives its filesystem
> type as 'BAD' rather than 'FreeBSD/i386', as it used to. Weirdly,
> Boot Magic (bundled with Partition Magic) found both operating systems
> with no difficulty.
>>

Perhaps something changed the partition type code in the MBR partition
table on your FreeBSD disk.  Do "fdisk ad1" to display the MBR partition
table.  The FreeBSD slice should say:

	sysid 165,(FreeBSD/NetBSD/386BSD)

If it says anything else, you can use the command "fdisk -u ad1" to
change the MBR partition type code back to 165 (decimal).

(Which release of FreeBSD do you run?  You used the "bsdlabel" command
to display the FreeBSD disk label on /dev/ad1s1.  That suggests you
are running FreeBSD 5.x.  In my experience, release 5.x won't recognize
FreeBSD disk labels in non FreeBSD slices and won't create special
files for the partitions in /dev.  This suggests that your MBR partition
type code is actually correct.  I dunno ... but it should be worth
checking anyway.)

Dan Strick