[ale] erasing a hard drive

[Fred Dinkler IV]

Hi,
Erase seems to be a vague term depending on your context and level of
paranoia. Here are some more precice terms / methods people use to
"Erase" their drive

Reformat
	re-creates a file system
	Will protact your data from people that dont have any knowledge
	nearly full data recovery possible, most formats do not seek and remove
backup file tables, simple recovery possible
	example linux command: mkfs.ext2 /dev/sda1

repartition
	re-draws file system boundaries
	barely better than reformat
	nearly full data recovery possible, have to seek for backup file
tables, data cutter (foremost) also very effective
	example linux command: fdisk /dev/sda

reinstall OS
	Usually used with repartition and reformat
	overwrites random data in relation to previous data, but will typically
occupy the same footprint as previous OS install
	large amount of data recovery still possible with data cutter (ie
foremost )
	
zero drive
	blanks all data with zeros
	software recovery impossible
	recovery with Magnetic force microscope
	example linux command: dd if=/dev/zero of=/dev/sda

shred drive
	repeated over write of drive with structured, random, and blank data
	no known recovery options
	utilities such as DBAN and *nix shred command

physical destruction
	if you simply snap the platter in half the halves can be subject to
Magnetic force microscope recovery.
	Thermite is widely accepted as thorough in its destruction of the drive
platters and silicon buffers that data could be read from. Also very
dangerous to handle. Let me say that again, as it cannot be understated,
very dangerous to handle. Once you light it you cannot extinguish it.
Thermite is dangerous.

I have no good information on demagnetizers

so, unless you are in the intelligence or finacncial industries, zero
the drive and be done with it. if you are in inteligence or finacncial
industries hire someone like iron mountain to take care of it, they have
shredders that can eat volvos, hard drive confetti is pretty thoroughly
"erased"
	
Thermite is dangerous.

On 08/26/2011 07:21 AM, Geoffrey Myers wrote:
> I've drawn a blank.  What is the name of that free software that I can 
> use to erase a hard drive?  It will run multiple overwrites?
> 
> I've got a number of old drives I need to dispose of and I don't want to 
> bother trying to figure out what's on them.
>