UNIX for Advanced & Expert Users

A colleague has friends in the data recovery business. They recommended 25 runs with shred in order to make it reasonably hard for them to recover the data; ten runs would be something they could routinely cope with. Still, modern hardware maps out bad sectors on the fly, and you then can't shred those mapped-out sectors, so their ultimate recommendation is physical destruction. Strong magnets I would have thought would be a good approximation, but apparently redoubtable thinks otherwise?

era I'm not quite sure about the magnets, I just heard that it was possible to predict the modifications and reverse them. But this is not even close to my areas of expertise so I can't be sure. I was hopping someone would also explain that when I opened the thread.

That's a good point. The hard disk has some sectors reserved to replace others when they become unusable and although those sectors (being bad and all) cannot be read from or written to by the kernel, they can still be read using special microscopes and some information can still be recovered.

Watch it Shred!: Hard Drives ;-)

A drill is a little neater than the hammer