To overwrite a partition or hard drive, two examples:
shred -vfuz -n 10 /dev/md1
shred -vfuz -n 10 /dev/sda
-v: show progress
-f: change permissions to allow writing if necessary
-u: truncate and remove file after overwriting (to shred occupied space with files)
-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.
http://linux.about.com/library/cmd/blcmdl1_shred.htm
http://www.howtoforge.com/how-to-securely-destroy-wipe-data-on-hard-drives-with-shred
Advertisements