9 Mar
2011
9 Mar
'11
9:46 p.m.
Jerome H. Fine wrote:
If the secure erase feature is not available, then if
it can be assumed
that there are no bad blocks with valid date and hidden away, about
how many time does it take to completely erase a hard disk drive block
for both ATA and non-ATA hard drive beyond all possibility of recovery?
On drives with older recording technology (MFM or RLL), three passes of
random data should be enough, though the military standard used more
passes, some with fixed patterns and some random.
On modern drives using PRML (as they all do these days), one pass with
random data should be enough, but do several just to be certain.
I saw a paper about this a year or two ago, but can't find it at the moment.
Eric