On Jun 7, 2009, at 12:06 PM, Niki Kovacs wrote: > Rainer Duffner a écrit : > >> Ideally, the zero'ing of the disk should take place before the OS is >> installed, via a boot-cd and using dd with the disk-device itself > > Erm... how exactly would you go about that? Let's say I want to do > that > with a Knoppix boot CD, and the only hard disk I have on the PC is > /dev/hdc. I've done the zeroing out thing on mounted filesystems before when I wanted to move the contents of a drive to another. zeroing out before would be best if you planned to do an install, then back it up for later. Otherwise, you end up with a lot of unused space that has remnants of old data scattered around. It does take awhile. Especially if you stuck the disk in an USB enclosure.