shred - delete files securely

erases whole partitions by overwriting everything with 0s in a single iteration.

shred -vzn 0 /dev/<device>

where <device> refers to your hard drive partition or device

example

# shred-vzn 0 /dev/sdc1

erases the whole partition using 3 iterations with random numbers. In addition (option -z) writes zeros to hide the shredding process at the end. This will take 4 times longer than the fast method.

shred -vzn 3 /dev/<device>

where <device> refers to your hard drive partition or device

example

# shred-vzn 3 /dev/sdc1