

Ask HN: Best way to wipe a disk? - zw123456

What is the best way to wipe a disk:
1) write all 1&#x27;s
2) write all 0&#x27;s
3) write alternating 1&#x27;s &amp; 0&#x27;s or other pattern
4) write random patters
5) write fake data, that is mark sectors as deleted but then fill them with words, perhaps random text from news articles off the web for example.
======
nabla9
It does not matter. "Basically the change in track density and the related
changes in the storage medium have created a situation where the acts of
clearing and purging the media have converged. That is, for ATA disk drives
manufactured after 2001 (over 15 GB) clearing by overwriting the media once is
adequate to protect the media from both keyboard and laboratory attack."
[http://csrc.nist.gov/publications/nistpubs/800-88/NISTSP800-...](http://csrc.nist.gov/publications/nistpubs/800-88/NISTSP800-88_with-
errata.pdf)

If somebody knows disc recovery firm that claims the ability to rescue data
from modern hdd after

    
    
        dd if=/dev/zero of=/dev/sda bs=1M
    

let me know.

Don't forget secure erase command. It clears even hidden data areas:

    
    
        hdparm  --security-erase Eins /dev/sda

------
anthony_franco
If you have a HDD (and maybe with SSD, not sure), the drive won't read/write
to any bad sectors you might have. If that's the case, then a software
solution won't completely wipe your drive. You'd most likely have to take the
drive apart and apply a strong magnet on each of the platters. Or, as
previously suggested, "FIRE!".

------
wikwocket
DBAN (Darik's Boot And Nuke) is my favorite solution. You can put it on a
bootable CD, bypass your OS, and just wipe the disks easily.

Here is a link to a bunch of other solutions as well:
[http://superuser.com/questions/4678/securely-erasing-all-
dat...](http://superuser.com/questions/4678/securely-erasing-all-data-from-a-
hard-drive)

------
2close4comfort
FIRE! or Over-writing about 7 times but I usually go for the first one unless
it is trivial data.

------
junto
If you are paranoid - Thermite

