FYI: Wiping a hard drive really clean

[Mike Reinehr]

On Thursday 26 May 2005 07:58 am, Matthew Carpenter wrote:
> Mike Reinehr wrote:
> > On Monday 23 May 2005 09:15 am, Michael Hipp wrote:
> >> The topic of how to wipe a hard drive truly clean has come up a
> >> couple of times. There's a good article on DistroWatch Weekly
> >> about it:
> >>
> >> http://distrowatch.com/weekly.php?issue=20050523#osa
> >>
> >> Michael
> >
> > Out of curiosity, couldn't you accomplish the same thing as DBAN by
> > booting your PC from Knoppix and then running dd if=/dev/random
> > of=/dev/hda ... a few times, i.e., 3, 7, 23, etc.?
> >
> > Alternatively, I seem to recall reading about encrypted file
> > systems, but don't know any details.
> >
> > cmr
>
> 7 is the magic number (supposedly).  I do know that the government has
> the capacity to pull off data which has been overwritten at least 3
> times.  From there, results are patchy.
> crypto-fs's are a mixed bag.  Microsoft's (of course) is simple to
> crack.  Others are better, but it depends on the implementation.
>
> As for /dev/random, that should work, although I think it would take
> longer.  I'm about to wipe some 1TB drives, I'll do some statitics,
> although it may prove that USB is the limiting factor on this system.  :(

	I just threw out /dev/random on a whim. I imagine that there might be a 
particular pattern, like is used in testing RAM, that might guarantee a 
successfull wipe in fewer passes.

Cheers!

cmr

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