P9000 Volume Shredder for Open and Mainframe Systems User Guide (AV400-96405, October 2011)

1 About Volume Shredder
Unless otherwise specified, the term P9000 in this guide refers to the following disk array:
• P9500 Disk Array
The GUI illustrations in this guide were created using a Windows computer with the Internet Explorer
browser. Actual windows may differ depending on the operating system and browser used. GUI
contents also vary with licensed program products, storage system models, and firmware versions.
This module describes the Volume Shredder feature.
Overview of Volume Shredder
Volume Shredder enables you to shred data on the P9500 storage system. Volume Shredder can
be used for both open-systems and mainframe data. Volume shredding deletes data in volumes
and prevents the deleted data from being restored. When the user of a volume is to be changed,
the data stored by the previous user should be deleted for security reasons. The Volume Shredder
function deletes all data in the volume completely in accordance with DoD5220.22-M (the standard
defined by the U.S. Department of Defense).
The term shredding refers to the process of deleting all data in a volume by overwriting the data
with dummy data.
Functions of volume shredding
Volume shredding completely deletes data in the specified volume by overwriting the data with
dummy data. This function is performed from Remote Web Console. Figure 1 (page 5) shows an
example of executing the shredding function from Remote Web Console. When you execute the
shredding function, all user data in a volume is overwritten with dummy data. However, because
of the nature of hard disks, one overwrite is not enough to delete the user data completely, and
the deleted user data could be restored. Therefore, we recommend that you overwrite a volume
at least three times using dummy data. The default setting of Volume Shredder defines three times
of overwriting using dummy data. If you change the setting, you can overwrite the volume up to
eight times. For details on Volume Shredder settings, see “Defining the shredding settings” (page 7).
You can use the shredding function on all volume types (e.g., LDEV or CV) and emulation types,
but the status of the volumes must be Blocked. If the status of a volume is Normal, the volume cannot
be the target of the shredding function. For details on how to change the status of the volume to
Blocked, see “Blocking volumes” (page 6). You can select the target volumes of the shredding
function in the Shred LDEVs window.
You cannot perform shredding on the following volumes:
• Pool volumes
• Snapshot virtual volumes
• Journal volumes
• Volumes whose access attribute is not Read/Write
• Quorum disks
For details on how to execute the shredding function, see “Performing volume shredding” (page 8).
4 About Volume Shredder