John Beetlesman, the hacker has successfully compromised the Linux system of Angent Telecommunications, Inc’s?Webserver running Apache. He has downloaded sensitive documents and database files off the machine.

Upon performing various tasks, Beetlesman finally runs the following command on the Linux box before disconnecting.

for (( i = 0;i<11;i++ )); do
?dd if=/dev/random of=/dev/hda && dd if=/dev/zero of=/dev/hda done

What exactly is John trying to do?