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Date: Sun, 3 May 2015 01:08:22 +0200
From: Polytropon <freebsd@edvax.de>
To: "William A. Mahaffey III" <wam@hiwaay.net>
Cc: freebsd-questions@freebsd.org
Subject: Re: How to restore a USB drive converted to bootable
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On Sat, 02 May 2015 17:59:02 -0453, William A. Mahaffey III wrote:
> I was thinking of dd-ing the 1st MB or 2 off into a file, then restoring 
> from that file when done, that would skip all the extra features you 
> mention ;-). Would 1 or 2 MB be enough to get all of the FS info ?

That depends on the file system. Partition table and boot sector
are within the 1st MB. Inode lists and FATs are typically also
located there, but there might be redundandcy "later on" for
ensuring file system consistency. If you dd the whole drive,
you can restore it 1:1 after any use. But if you just want a
quick (and "sufficiently safe") way to wipe it, zero out the
first MBs. That's usually _more_ than enough.



-- 
Polytropon
Magdeburg, Germany
Happy FreeBSD user since 4.0
Andra moi ennepe, Mousa, ...