wipe /dev/sda

[Kevin O'Gorman]

On Tue, Jul 14, 2009 at 6:55 AM, Gregg Hastings<a47496 at tyldd.com> wrote:
> I have a disk I'm getting rid of via eBay.  For whatever reason I can't
> get DBAN to load on that laptop.  I was thinking about doing dd
> if=/dev/urandom of=/dev/sda from knoppix but then I ran across wipe.
>
> After looking over the man page I can't decided which, if any, options
> to include with wipe /dev/sda.
>
> Can anyone point me in the right direction?  From what I read it will be
> doing a 34 pass wipe by default with no options present.  Which is fine
> for the information the disk used to hold.  Nothing overly sensitive.
>
> Experiences?

What threat do you envision?  Spies spending a year recovering bits
from your disk?

I've always been content with coping /dev/zero onto the whole disk or
partition.  Now that I've learned from you about /dev/urandom, I'll
use that.

I use a cross-cut shredder on all my trash that has dollar amounts or
account numbers, and still consider that to be a greater vulnerability
than a drive that's been wiped with /dev/zero.  One could get useful
information with merely a hundred hours or so of low-tech jigsawing.
But I really don't think that's going to happen unless some reader
takes this up as a challenge.

You've got to draw the line somewhere, and the choice is a bit
arbitrary.  I'm not going to pour cement or acid into my shredder
bags, and I'm not going to do 34 passes on a dead drive.

YMMV.

-- 
Kevin O'Gorman, PhD