HowTo Completely Wipe Data From Hard Disk With Xubuntu

I had to erase all data from Laptop which had top secret material on it. This is how to wipe all data from hard drive with Linux.

1. First create bootable Linux cd or usb stick.
2. Open terminal and see if you have shred installed by typing: which shred
3. If it not installed you can install it with: apt-get install coreutils
4. Figure out which hard drive you want to erase: sudo fdisk -l
5. Wipe out disk (/dev/sda is the name or location of the disk): sudo shred -vfz -n 10 /dev/sda5

v: show progress
-f: change permissions to allow writing if necessary
-z: add a final overwrite with zeros to hide shredding
-n: overwrite N times instead of the default (3)

So this would overwrite /dev/sda5 ten times.

Original: http://www.howtoforge.com/how-to-securely-destroy-wipe-data-on-hard-drives-with-shred