Mark Hull-Richter wrote: > Capstone (so to speak): > > I booted from the Seagate CD and ran both the quick and full > diagnostics on the disk. It failed them both. > > Now I'm wondering what's the best way to destroy all the data on the > drive so I can return it without my stuff, unreliable or not, on it. > > I suppose a dd from /dev/zero to the whole disk might work - am I > right? I'm not sure what block size or how many - it's a 400Gb drive.... the block size doesn't matter except for performance. use 1048576 (1MB) or something. Alternately, run the seatools destructive sequential write w/ random data diagnostic, at least 2 full passes of random data will completely scramble any residual data beyond any possibility of recovery. the old DOD standard 1111, 1010, 1100, 0011, 0101, 0000 thing is obsolete, and was based on MFM/ESDI/PLL bit encoding patterns, which no longer apply to modern disks... but, if the drives failed the diagnostics, it may not even let you write patterns over the full media. I suppose you might explain your data destruction requirements (are these corporate policy, or government/military based, or just personal policy?) to the Seagate customer services people, and ask for their guidance. surely, they have a provision for this as it can't be uncommon... they probably won't let you physically destroy the drive, as I've heard something like 80% of drive returns are retested and turn out to be 100% AOK, and can be reformatted, 'refurbished', and put back in service.