Hi there,

When getting rid of an old NX4 array, what is the best way to DoD wipe the drives?

Thanks,

Hi Karen,
We have dealt with this quite a bit.  We were selling an old storage system that had emulated tape data on it.  The storage system was old enough that it didn't support encrypted drives so there wasn't any encryption key that we could change that instantly renders the data nonretrievable.  So, we came up with an AIX Shell script to write binary zeros to the volumes.  Before doing this, though, we deleted all the volumes and then redefined much larger ones so we didn't have so many to deal with.  This script is somewhat self explanatory with the comments.  This script will first clear the data from the drive by writing binary zeros across the entire drive in 4MB chunks.  It then displays portions of each volume to verify the writing was successful.  Here's the kornshell script that we used that we called disk_erase.sh:

**********Start of Script**********

#!/bin/ksh
#

hd="${1}"

/bin/date

#  Write zeros to the entire disk
/bin/dd if=/dev/zero of=/dev/r${hd} bs=4096k
print

#  Display data at 1/8 of the disk
/usr/sbin/lquerypv -h /dev/${hd} 7468600000
print

#  Display data at 1/4 of the disk
/usr/sbin/lquerypv -h /dev/${hd} e8d0a00000
print

#  Display data at 3/8 of the disk
/usr/sbin/lquerypv -h /dev/${hd} 15d38e00000
print

#  Display data at 1/2 of the disk
/usr/sbin/lquerypv -h /dev/${hd} 1d1a1200000
print

#  Display data at 5/8 of the disk
/usr/sbin/lquerypv -h /dev/${hd} 24609600000
print

#  Display data at 3/4 of the disk
/usr/sbin/lquerypv -h /dev/${hd} 2ba71a00000
print

#  Display data at 7/8 of the disk
/usr/sbin/lquerypv -h /dev/${hd} 32ed9e00000
print

#  Display data at the end of the disk
/usr/sbin/lquerypv -h /dev/${hd} 3a3421fff00

/bin/date

**********End of Script**********

Here is what the execution of this script would look like in AIX:

./disk_erase.sh hdiskn          where hdiskn is the name of the hdisk. 

Depending on the size of each volume, it will take a couple of hours for each one if they are multiple TB volumes, but we were fairly satisfied that we wiped the data from the drive. This was lesser expensive than the retail utilities that are available out in the market place.

Hope this helps.

Thank You.

Gary Monroe

SpartanNash Co.