I was in the process of securely wiping some disks on a Linux box when I did a df and got the following output:
demo@x225:~$ df -h Filesystem Size Used Avail Use% Mounted on /dev/sda1 130G 2.7G 120G 3% / none 1003M 372K 1003M 1% /dev none 1007M 248K 1007M 1% /dev/shm none 1007M 96K 1007M 1% /var/run none 1007M 0 1007M 0% /var/lock none 1007M 0 1007M 0% /lib/init/rw none 130G 2.7G 120G 3% /var/lib/ureadahead/debugfs /dev/sdb1 43Z 43Z 0 100% /u1 /dev/sdc1 4.0Z 4.0Z 0 100% /u2
The last two disks, sdb1 and sdc1 are being securely erased and they are reporting 43ZB and 4ZB respectively – yes, ZETTABYES. I really wish it was true!
According to Wikipedia, a zettabyte is “… is equal to 1,073,741,824 (~ 1 billion) terabytes” and “As of April 2012, no storage system has achieved one zettabyte of information. The combined space of all computer hard drives in the world was estimated at approximately 160 exabytes in 2006.”