On Thursday 28 May 2009, Robert L Cochran wrote:
I have a hard drive that I need to destroy the data on. What is the most dependable way to do this? Can reformatting the drive as ext3 or ext4 or some other filesystem effectively destroy the existing data?
Is there free software that can write zeroes or some form of nonsense to every storage location?
dd if=/dev/urandom of=/dev/(ice) repeated 3 or so times should pretty well destroy any attempts to recover any valid data from that drive. Don't use the partition, such as /dev/sda1, but the whole drive, /dev/sda which should also get the partition tables.
Formatting a hard drive just installs a new inode framework and root directory. The data itself is still there for something as simple as: dd if=/dev/sdX which will spit it all out to the screen with only the holes created by the installation of a new filesystem framework being invalid.
But /dev/urandom written to everything 3 or more times should render the data unrecoverable unless they wanna call out the guys with the electron microscopes to read the edges of the track byte by byte.
Thanks
Bob Cochran