How to make sure it's really gone?

[Technomage]

badblocks is useful for this (someone else a long time ago posted a command 
line for badblocks that would make data on the drive truly non-recoverable).

here's the command line I used:

badblocks -f -t random -p 30 -sv -w /dev/<device>

this command will take a very long time to run on any of the large >10 GB 
drives BUT, it will insure that no usable data of any kind remains afterward 
(even the NSA would have a heart attack on this).

my scenario for a full wipe involves this:

dd if=/dev/zero of=/dev/<device> && dd if=/dev/urandom of=/dev/<device> && 
badblocks -f -t random -p 30 -sv -w /dev/<device>

that can be placed in a script and run as many times as you see fit. However, 
with 30 passes in the badblocks in -w mode, you can pretty much be assured 
that no data will exist afterward.

more comments?


On Saturday 21 October 2006 17:24, Jim wrote:
> Let's assume I have some data on a Dreiser's or ext3 partition.  Short
> of removing the drive and smashing it, how can I make sure with
> reasonable certainty the data is gone?
>
> I looked at the manage for shred and it says it doesn't work on
> journaled file systems such as ReiserFS, Ext3 and others.  Is there
> something that will do the job on an ext3 or reiserfs partition?
>
> Thanks