John john at
Thu Jan 20 08:12:05 PST 2005

On Thu, Jan 20, 2005 at 03:52:29PM +0100, Anthony Atkielski wrote:
> Colin J. Raven writes:
> CJR> I always thought that formatting/fdisk'ing twice completely erased
> CJR> *permanently* whatever had been on the disc.
> Information can be recovered from disks even after a dozen or more
> overwrites.  The data is never safe with the platters intact.

Good gosh, what are you people doing on your machines - designing
weapons systems?

What what you are all saying is TRUE, it is not TRIVIAL.  After
a "security erase" on a disk drive, or a full over-write, it
takes increasingly sophisticated levels of lab equipement and
environments to do the sort of things that you are describing -
including disassembly and clean-room stuff.  In otherwords, someone
has to be willing to invest at least a few hundred dollars (if it
has simply been overwritten) to several THOUSAND dollars to do
these sorts of recoveries, and some patience, because it takes
TIME, and often, like million-year-old DNA, there are gaps that
need to be reconstructed.

What do you folks have on your hard drives that is worth thousands
of dollars and weeks of time for someone to recover?

If it was as easy as you describe, we'd rarely need backups.  Your
disk drive crash?  Oh, just bring it to the local recovery service
and they'll get all your data back for $9.95.  NOT!!!!

John Lind
john at starfire.MN.ORG

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