How to completely erase a hard disk

[Bart Silverstrim]

Gabriel Dragffy wrote:
> On 1 Oct 2007, at 03:31, Twist O'Connor wrote:
> 
>> umm yea you can really just use the ubuntu live cd and manuelly  
>> setup your partitions..... i suggest alternet cd for more control  
>> over your situation
>>
> 
> That didn't work. I tried deleteing all partitions, reformating them  
> before and after, and even reformating the block device dd if=/dev/ 
> zero was the way I found. But you could use mdadm --zero-blocks  but  
> that didn't work for me for some reason.

Big electromagnet?