[svlug] 2 part Linux question

[Marc Maxwell]

Hello Linux Gurus and Penguinoids,

I am curious about a couple of things. I want to wipe
data off of an IDE drive COMPLETELY, absolutely and
totally gone forever and NOT recoverable.  I have
recently learned to my dismay that formats and even
the utilities that write ones and zeroes to the drive,
are really not completely erasing the data.  

Part 1.  I am curious about using dd for this.  My
understanding is you can say something like:

# dd if==/dev/hda of=/dev/urandom

I heard that you have to do this multiple times.  Does
anyone know if that is true?  If so, how many times
and why?  Also, the dd command *will* work ((it does
something, but it doesn't print hash marks or give you
a percentage done or anything like that).  So how long
do you let it run?  Ten instances of 2 minutes each? 
One instance of Five hours?  A whole day per instance
(times however many you have to repeat the process)? 
Does the size of the drive matter?

I am definitely not hung up on dd; if there is another
better utility please let me know, 3rd parties welcome
if they are good.

Part 2.  Is there a way to encrypt a drive under
linux? This is less important than the first question
just a fyi for me.

Any info is appreciated.  Thanks,

=====
Marc Maxwell
Registered Linux user # 319836
Linux- the Operating System of the 21st Century

__________________________________
Do you Yahoo!?
SBC Yahoo! DSL - Now only $29.95 per month!
http://sbc.yahoo.com