sanitizing disc

[Karl Auer]

On Thu, 2014-01-30 at 17:07 +0100, Gary Kirkpatrick wrote:
> I have ubuntu 13.10 installed on an external harddrive which I have
> been using so it has my files on it.  I am going to give the drive to
> a friend.  What is the best way to remove my files from the drive?  I
> could just reinstall ubuntu but short of that is there anything I can
> do to sanitize the disk?  How about make another user and delete my
> original user? 

If you just delete the files, the data remains on disk and can be
reconstructed. In fact, it is quite easy to reconstruct, and there are
programs that will do it for you. Even formatting the disk will not
remove all the data.

To properly sanitise a disk, hit it several times with a large
sledgehammer :-)

Alternatively, use "shred". This takes a long time, but will very
effectively destroy all the data on a disk. Read the man page though,
because there are some limitations depending on the type of disk and the
disk format.

   sudo shred /dev/whatever

Regards, K.

-- 
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Karl Auer (kauer at biplane.com.au)
http://www.biplane.com.au/kauer
http://twitter.com/kauer389

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