On 04/01/2008, at 8:19 AM, Brad Tilley wrote:
One pass from /dev/zero is more than enough for all cases.
I agree that after a single pass of zeroes, getting anything but zeroes from a fully working, unaltered drive is not going to happen.
But if you remove the digital logic which masks residual signals via thresholds used to determine at what point a 1 is considered a 1 and a 0 a 0, then perhaps 1's and 0's could be restored from some drives. Through the use of a replacement device that samples each bit with a bit depth greater than 1, allowing analysis to interpret what I would have thought would not be constant uniform samples.
I think more importantly, if it is comparatively very cheap to erase a drive in a paranoid manner and the leaking of that data could cost a fortune, then the comparatively small cost of paranoid erasure could be a risk worth taking.
Shane
