Question on shredding a terebyte drive

[Marko Vojinovic]

On Wednesday 02 September 2009 21:32:32 Dean S. Messing wrote:
> I have a terebyte sata drive that I need to securely wipe clean.  It
> originally had 2 partitions.  I deleted them using `fdisk', rebooted,
> and then as root ran
>
>     shred -vz /dev/sdd
>
> The drive is capable of about 60MB/sec, but shred is only "shredding"
> about 25MB every 5 seconds according to its output.  Since the default
> number of passes is 25, this works out to about 5 days.

I have always wondered about this, why not just do a rm -rf *  on the drive, 
then put one big file on it (some divx movie or such), and copy it over and 
over under different names until the drive space gets exhausted completely? 
This can easily be scripted, and I believe it would work as fast as possible 
for a drive of given capacity.

The idea is that drive has a limited capacity overall, so if you do this a 
couple of times, there will be no way of recovering any sensitive previously 
deleted data. A drive can remember only so many bits, eventually all storage 
space will get exhausted/overwritten...

Or am I missing something?

Best, :-)
Marko