erase_disks() {
   for disk in `lsblk -d -n -oKNAME,TYPE,RO | grep '^\w*\s*disk\s*0' | awk {'print $1'}`
   do
      echo "Erasing $disk..."
      bytes=$(blockdev --getsize64 /dev/$disk)
      head -c $bytes /dev/zero > /dev/$disk
   done
}