[unisog] Wiping hard drives before computer transfer

Martin Radford Martin.Radford at bristol.ac.uk
Fri Jan 24 16:55:10 GMT 2003


--On 23 January 2003 16:14 -0600 Marty Hoag <Marty.Hoag at ndsu.nodak.edu>
wrote:

>     I'm curious what others are doing to remove data and
> software from hard drives of surplused or "passed down"
> PCs and Macs.  Besides things like FERPA and licensed
> software concerns, there could be some liability if we
> passed along a machine which had already be compromised
> and potential embarrassment of revealing old data.

We use a tool I wrote which simply writes ASCII NULs across the disk,
together with a counter at the end of each megabyte.  It then goes back
and checks that the disk looks as it expected.

The write up is at
http://www.bris.ac.uk/is/services/computers/general/ubcswipe.html

I don't claim that this would be enough to thwart a determined
attacker, but it's enough to stop the embarassment of a system finding
its way onto the second hand market with confidential data that just
needs to be undeleted using a DOS tool.

It wouldn't be difficult to extend the tool to do multiple passes and
write random data if that was required.

Martin
-- 
Martin Radford  (Martin.Radford at bristol.ac.uk)
Personal Computer Systems Team
Information Systems & Computing
University of Bristol Information Services
PGP keyID:       5D2D92E9
PGP fingerprint: 137E 0277 9D78 7447 71D0 BB3D C20D BB9A 5D2D 92E9



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