Hitachi G1000 User manual

Product Version
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Getting Help
F AST F IND L INKS
Hitachi Virtual Storage Platform G1000
Hitachi Volume Shredder User Guide
MK-92RD8025-01

Hitachi Virtual Storage Platform G1000 Hitachi Volume Shredder User Guide
ii
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iii
Hitachi Virtual Storage Platform G1000 Hitachi Volume Shredder User Guide
Contents
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v
Intended audience. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi
Product version . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi
Document revision level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi
Changes in this revision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi
Referenced documents. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi
Document conventions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi
Convention for storage capacity values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .viii
Accessing product documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .viii
Getting help . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .viii
Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .viii
1 Overview of Hitachi Volume Shredder . . . . . . . . . . . . . . . . . . . . . 1-1
Data security practices and Volume Shredder . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Supported volume types. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Volume Shredder operations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Shredding times . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
2 Volume Shredder operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
Workflow for shredding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
Blocking a volume . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
Blocking volumes in a parity group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
Calculating the number of overwrite passes for flash drives . . . . . . . . . . . . . . . 2-4
Example of shredding data on flash drives . . . . . . . . . . . . . . . . . . . . . . . . 2-4
Calculating the number of overwrite passes for FMDs . . . . . . . . . . . . . . . . . . . 2-5
Example of shredding data on FMDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6
Defining shredding conditions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6
Shredding a volume. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
Shredding volumes in parity groups. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
Viewing shredding status with the Tasks window . . . . . . . . . . . . . . . . . . . . . . 2-9
Viewing shredding status with the Logical Devices window . . . . . . . . . . . . . . 2-10

Hitachi Virtual Storage Platform G1000 Hitachi Volume Shredder User Guide
iv
Stopping a shredding operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10
Viewing shredding results with the Tasks window . . . . . . . . . . . . . . . . . . . . . 2-11
Viewing shredding results in the compressed files . . . . . . . . . . . . . . . . . . . . 2-12
A Volume Shredder GUI reference . . . . . . . . . . . . . . . . . . . . . . . . . A-1
Shred LDEVs wizard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-2
Shred LDEVs window . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-2
Shred LDEVs wizard Confirm window . . . . . . . . . . . . . . . . . . . . . . . . . . . A-3
Edit Shredding Data Pattern window . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-5
Index

Preface v
Hitachi Virtual Storage Platform G1000 Hitachi Volume Shredder User Guide
Preface
This guide describes and provides instructions for Hitachi Volume Shredder
secure erase software for the Hitachi Virtual Storage Platform G1000
storage system.
Read this document carefully to understand how to use this product, and
maintain a copy for reference purposes.
This preface includes the following information:
□Intended audience
□Product version
□Document revision level
□Changes in this revision
□Referenced documents
□Document conventions
□Convention for storage capacity values
□Accessing product documentation
□Getting help
□Comments

Hitachi Virtual Storage Platform G1000 Hitachi Volume Shredder User Guide
vi Preface
Intended audience
This document is intended for system administrators, HDS representatives,
and authorized service providers who install, configure, and operate the
Hitachi Virtual Storage Platform G1000 storage system.
Readers of this document should be familiar with the following:
• Data processing and RAID storage systems and their basic functions.
• The Hitachi Virtual Storage Platform G1000 storage system and the
Hitachi Virtual Storage Platform G1000 Hardware Guide.
• The Hitachi Command Suite software or the Hitachi Device Manager -
Storage Navigator software for the Hitachi Virtual Storage Platform
G1000 storage system and the Hitachi Command Suite User Guide or
the Mainframe System Administrator Guide.
• Data protection and security practices in enterprise storage
environments, including data retention, archival, and shredding.
Product version
This document revision applies to Hitachi Virtual Storage Platform G1000
microcode 80-01-4xor later.
Document revision level
Changes in this revision
• Added information about using Hitachi Command Suite to perform
Volume Shredder operations.
Referenced documents
Hitachi Virtual Storage Platform G1000 documents:
•Hitachi Virtual Storage Platform G1000 Hardware Guide, MK-92RD8007
•Hitachi Virtual Storage Platform G1000 Provisioning Guide for Open
Systems, MK-92RD8014
•Hitachi Virtual Storage Platform G1000 Mainframe System Administrator
Guide, MK-92RD8016
•Hitachi Command Suite Messages, MK-92RD8017
Document conventions
This document uses the following terminology conventions:
Revision Date Description
MK-92RD8025-00 April 2014 Initial release
MK-92RD8025-01 August 2014 Supersedes and replaces MK-92RD8025-00

Preface vii
Hitachi Virtual Storage Platform G1000 Hitachi Volume Shredder User Guide
This document uses the following typographic conventions:
The following table lists note icons that might appear in this document.
Convention Description
Hitachi Virtual Storage
Platform G1000
Refers to all models of the Hitachi Virtual Storage Platform
G1000 storage system, unless otherwise noted.
Convention Description
Bold Indicates the following:
• Text in a window or dialog box, such as menus, menu
options, buttons, and labels. Example: On the Add Pair
dialog box, click OK.
• Text appearing on screen or entered by the user. Example:
The -split option.
• The name of a directory, folder, or file. Example: The
horcm.conf file.
Italic Indicates a variable, which is a placeholder for actual text
provided by the user or system. Used for variables in regular
text. Example: copy source-file target-file
Monospace Indicates text that is displayed on screen or entered by the
user. Example: # pairdisplay -g oradb
< > angle brackets Indicates a variable, which is a placeholder for actual text
provided by the user or system. Used for variables in
monospace text. Example: # pairdisplay -g <group>
[ ] square brackets Indicates optional values. Example: [ a | b ] indicates that you
can choose a, b, or nothing.
{ } braces Indicates required or expected values. Example: { a | b }
indicates that you must choose either a or b.
| vertical bar Indicates that you have a choice between two or more options
or arguments. Examples:
[ a | b ] indicates that you can choose a, b, or nothing.
{ a | b } indicates that you must choose either a or b.
Icon Meaning Description
Tip Provides information, guidelines, or suggestions for
performing tasks more effectively.
Note Calls attention to additional information.
Caution Warns that failure to take or avoid a specified action can
result in adverse conditions or consequences (for example,
loss of access to data).
WARNING Warns that failure to take or avoid a specified action can
result in severe conditions or consequences (for example,
loss of data).

Hitachi Virtual Storage Platform G1000 Hitachi Volume Shredder User Guide
viii Preface
Convention for storage capacity values
Physical storage capacity values (for example, data drive capacity) are
calculated based on the following values:
Logical storage capacity values (for example, logical device capacity) are
calculated based on the following values:
Accessing product documentation
The Hitachi Virtual Storage Platform G1000 user documentation is available
on the Hitachi Data Systems Portal: https://portal.hds.com. Please check
this site for the most current documentation, including important updates
that may have been made after the release of the product.
Getting help
The Hitachi Data Systems customer support staff is available 24 hours a
day, seven days a week. If you need technical support, log on to the Hitachi
Data Systems Portal for contact information: https://portal.hds.com
Comments
Please send us your comments on this document [email protected].
Include the document title and number, including the revision level (for
example, -07), and refer to specific sections and paragraphs whenever
possible. All comments become the property of Hitachi Data Systems.
Thank you!
Physical capacity unit Value
1 KB 1,000 (103) bytes
1 MB 1,000 KB or 1,0002bytes
1 GB 1,000 MB or 1,0003bytes
1 TB 1,000 GB or 1,0004bytes
1 PB 1,000 TB or 1,0005bytes
1 EB 1,000 PB or 1,0006bytes
Logical capacity unit Value
1 block 512 bytes
1 KB 1,024 (210) bytes
1 MB 1,024 KB or 1,0242bytes
1 GB 1,024 MB or 1,0243bytes
1 TB 1,024 GB or 1,0244bytes
1 PB 1,024 TB or 1,0245bytes
1 EB 1,024 PB or 1,0246bytes

1
Overview of Hitachi Volume Shredder 1–1
Hitachi Virtual Storage Platform G1000 Hitachi Volume Shredder User Guide
Overview of Hitachi Volume Shredder
This chapter provides an overview of Volume Shredder operations on the
Hitachi Virtual Storage Platform G1000 storage system.
□Data security practices and Volume Shredder
□Supported volume types
□Volume Shredder operations
□Shredding times

Hitachi Virtual Storage Platform G1000 Hitachi Volume Shredder User Guide
1–2 Overview of Hitachi Volume Shredder
Data security practices and Volume Shredder
The Volume Shredder software enables you to securely erase data on
volumes in the Hitachi Virtual Storage Platform G1000 storage system by
overwriting existing data to prevent restoration of the erased data. For
example, when the user of a volume changes, you may want to purge the
data stored by the previous user before giving access to the new user. This
method of erasing data by overwriting it with dummy data is referred to as
shredding.
Because of the way data is written on the drives, overwriting data once or
twice might not be enough to ensure that the data cannot be restored. The
best practice is to overwrite data at least three times with dummy data.
Volume Shredder allows you to specify the number of times the data is
overwritten, enabling you to ensure compliance with applicable
requirements (for example, DoD5220.22-M).
Supported volume types
You can use Volume Shredder to shred both open-systems and mainframe
systems, including logical devices (LDEVs) and custom volumes (CVs) of all
emulation types. External volumes and Dynamic Provisioning virtual
volumes* can also be shredded.
*When a shredding operation is performed on an unused virtual volume for
Dynamic Provisioning, no dummy data is written to the volume.
You cannot use Volume Shredder to shred the following types of volumes:
• Pool volumes
• Virtual volumes for Thin Image
•Journalvolumes
• Volumes that are not write-enabled (access attribute is not read/write)
•TSE-VOL
Volume Shredder operations
The following figure shows user data that is being overwritten three times
(default value for number of overwrites). Volume Shredder overwrites data
using the following dummy data values:
• The first overwrite is 00.
• The second overwrite is FF.
• The third overwrite is 00.

Overview of Hitachi Volume Shredder 1–3
Hitachi Virtual Storage Platform G1000 Hitachi Volume Shredder User Guide
You can configure Volume Shredder to overwrite data from three to eight
times, and each time the system overwrites the data you can configure the
dummy data to be any hexadecimal number from 0 to FFFF.
After the system finishes overwriting data, you can view the results in the
user interface or, if configured, you can open the compressed results files.
We recommend that you execute the shredding function at times of day
when the host I/O load is lowest. If the number of LDEVs to be shredded is
large, shredding operations might affect host I/O operations. Use the
following formula to determine the standard required time for a shredding
operation.
(time required for shredding) = (time required for one dummy data
write (standard required time)) x (number of times dummy data is
written (n))

Hitachi Virtual Storage Platform G1000 Hitachi Volume Shredder User Guide
1–4 Overview of Hitachi Volume Shredder
Shredding times
The following tables show the standard required times for shredding without
host I/O, listed by drive type. The same standard times also apply to
shredding encrypted drives. The standard required time in each table
assumes the use of OPEN-V volumes.
For DKxxx-JxxxSS/KxxxSS/HxxxSS disk drives:
For flash drives (SSDs):
For FMDs:
Rotation per
minute RAID level Standard required time*
15 Krpm RAID 1 2D+2D 85 minutes
RAID 5 3D+1P 65 minutes
7D+1P 30 minutes
RAID 6 6D+2P 35 minutes
14D+2P 20 minutes
10 Krpm RAID 1 2D+2D 110 minutes
RAID 5 3D+1P 70 minutes
7D+1P 35 minutes
RAID 6 6D+2P 35 minutes
14D+2P 20 minutes
7.2Krpm RAID 1 2D+2D 185 minutes
RAID 5 3D+1P 120 minutes
7D+1P 50 minutes
RAID 6 6D+2P 65 minutes
14D+2P 25 minutes
*Data drive capacity is assumed to be 1 TB.
Number of parity
groups RAID level Standard required time*
From 1 to 4 RAID 1 2D+2D 30 minutes
RAID 5 3D+1P 20 minutes
7D+1P 15 minutes
RAID 6 6D+2P 15 minutes
14D+2P 10 minutes
*Flash drive capacity is assumed to be 1 TB.

Overview of Hitachi Volume Shredder 1–5
Hitachi Virtual Storage Platform G1000 Hitachi Volume Shredder User Guide
When host I/Os are performed, the required shredding time is at least six
times that of when no host I/Os are performed. If a DKxxx-HxxxAT data
drive is used for creating a parity group on an encrypted data drive, the time
required for shredding that parity group is the maximum time listed.
If the volumes to be shredded belong to drives of mixed types or mixed
configurations, the longest required times associated with the drive type or
drive configuration apply to all volumes. Thus, mixed types and
configurations take more time for the volumes to become available for use
than when the drive type and drive configuration are the same. When you
add drives or change drive configurations, you should arrange the drives
into those with the same standard required times, and then add drives
starting with those volume types requiring the least shredding time.
Fibre-channel connectivity is required for both mainframe and open-
systems volumes.
Number of parity
groups RAID level Standard required time*
From 1 to 4 RAID 1 2D+2D 20 minutes
RAID 5 3D+1P 10 minutes
7D+1P 10 minutes
RAID 6 6D+2P 10 minutes
14D+2P 5 minutes
*FMD capacity is assumed to be 1 TB.

Hitachi Virtual Storage Platform G1000 Hitachi Volume Shredder User Guide
1–6 Overview of Hitachi Volume Shredder

2
Volume Shredder operations 2–1
Hitachi Virtual Storage Platform G1000 Hitachi Volume Shredder User Guide
Volume Shredder operations
This chapter describes and provides instructions for performing Hitachi
Volume Shredder operations:
□Workflow for shredding
□Blocking a volume
□Blocking volumes in a parity group
□Calculating the number of overwrite passes for flash drives
□Calculating the number of overwrite passes for FMDs
□Defining shredding conditions
□Shredding a volume
□Shredding volumes in parity groups
□Viewing shredding status with the Tasks window
□Viewing shredding status with the Logical Devices window
□Stopping a shredding operation
□Viewing shredding results with the Tasks window
□Viewing shredding results in the compressed files

Hitachi Virtual Storage Platform G1000 Hitachi Volume Shredder User Guide
2–2 Volume Shredder operations
Workflow for shredding
Use the following workflow to shred volumes using Volume Shredder:
1. Viewing shredding status with the Logical Devices window on page 2-10
(Volume status should be Normal.)
2. Blocking a volume on page 2-2
3. Calculating the number of overwrite passes for flash drives on page 2-4
if you are shredding a volume on a flash drive.
Or, Calculating the number of overwrite passes for FMDs on page 2-5 if
you are shredding a volume on an FMD.
4. Defining shredding conditions on page 2-6
5. Shredding a volume on page 2-7
6. Stopping a shredding operation on page 2-10
7. Viewing shredding results in the compressed files on page 2-12 to check
results in the results file.
Blocking a volume
You must have the Storage Administrator (Provisioning) role to perform this
task.
To block a volume:
1. Display the volume to be blocked:
In Hitachi Command Suite:
a. On the Resources tab, click Storage Systems, expand All
Storage Systems, and then expand the target storage system.
b. Right-click one of the following, depending on the location of the
volume, Volumes, DP Pools, or Parity Groups, and then select
System GUI.
c. If you selected DP Pools in step (b), select the pool that contains
the virtual volume you want to block, and then click the Virtual
Volumes tab.
In Device Manager - Storage Navigator (mainframe-only environment):
Choose one of the following steps, depending on the location of the
volume:
 To display t he LDEVs tab, in the Storage Systems tree, select
Parity Groups, Internal, or External, and then select the parity
group that contains the volume you want to block.
 To display t he LDEVs tab, in the Storage Systems tree, select
Logical Devices.
 To display t he Virtual Volumes tab, in the Storage Systems tree,
select Pools, and then select the pool that contains the virtual
volume you want to block.
2. Confirm the current status of the volume you want to block by viewing
the Status column of the table.

Volume Shredder operations 2–3
Hitachi Virtual Storage Platform G1000 Hitachi Volume Shredder User Guide
 If the volume is already blocked, Blocked appears in the status
column.
 If the volume is not blocked, a status other than Blocked appears in
the status column.
3. Select the volume you want to block, click More Actions, and then
select Block LDEVs. The Block LDEVs window opens.
4. Note the settings in the Block LDEVs window, enter a unique task name
or accept the default name, and then click Apply.
If Go to tasks window for status is selected, the Tasks window will
open.
Related topics
•TheBlock LDEVs section in the Hitachi Virtual Storage Platform G1000
Provisioning Guide for Open Systems.
•TheTop window when selecting Logical Device section in the Hitachi
Virtual Storage Platform G1000 Provisioning Guide for Open Systems.
•TheTop window when selecting Internal or External of Parity Group
section in the Hitachi Virtual Storage Platform G1000 Provisioning Guide
for Open Systems.
Blocking volumes in a parity group
You must have the Storage Administrator (Provisioning) role to perform this
task.
To block volumes in a parity group:
1. Display the parity group to be blocked:
In Hitachi Command Suite:
a. On the Resources tab, click Storage Systems, and then expand
All Storage Systems.
b. Expand the target storage system, right-click Parity Groups, and
then select System GUI.
In Device Manager - Storage Navigator (mainframe-only environment):
Display the Parity Groups tab by choosing one of the following steps,
depending on the location of the parity group:
 In the Storage Systems tree, select Parity Groups.
 In the Storage Systems tree, select Parity Groups and then select
Internal or External.
2. Confirm the current status of the volumes you want to block by viewing
the LDEV Status column of the table.
 If the volume is already blocked, Blocked appears in the status
column.
 If the volume is not blocked, a status other than Blocked appears in
the status column.
3. Select the parity group you want to block, click More Actions, and then
select Block LDEVs. The Block LDEVs window opens.

Hitachi Virtual Storage Platform G1000 Hitachi Volume Shredder User Guide
2–4 Volume Shredder operations
4. Note the settings in the Block LDEVs window, enter a unique task name
or accept the default name, and then click Apply.
If Go to tasks window for status is selected, the Tasks window will
open.
Related topics
•TheBlock LDEVs section in the Hitachi Virtual Storage Platform G1000
Provisioning Guide for Open Systems.
•TheTop window when selecting Logical Device section in the Hitachi
Virtual Storage Platform G1000 Provisioning Guide for Open Systems.
•TheTop window when selecting Internal or External of Parity Group
section in the Hitachi Virtual Storage Platform G1000 Provisioning Guide
for Open Systems.
Calculating the number of overwrite passes for flash
drives
Because of the way space is allocated in flash drives, the dummy data that
is used to overwrite the volume must exceed the capacity of the target
volume. Therefore, before you shred a volume on flash drives, you need to
calculate the number of times the system must overwrite the volume with
dummy data.
You must have the Storage Administrator (Provisioning) role to perform this
task.
1. Select an LDEV on the LDEVs tab in the Logical Devices window, and
write down its capacity and the amount of data in the RAID
configuration.
Examples of amounts of data in a RAID configuration:
n of RAID5(nxD + 1P)
n of RAID6(nxD + 2P)
2. Use the following formula to calculate the number of times to overwrite
the data (N):
N = (User-capacity-for-Data x 2) / Capacity-of-target-volume
When the capacity of the flash drive is 400 GB, 400 GB x n
Example: The capacity of the flash drive is 400 GB, the RAID
configuration is 3D+1P, and the LDEV capacity is 440 GB.
[(400 x 3) x 2 ] / 440 = 5.45 = six times
Round up the value (5.45) to the nearest whole number. You need to
overwrite the data six times.
Example of shredding data on flash drives
In this sample configuration, the flash drive capacity is 400 GB, the RAID
configuration is 3D+1P, and the LDEV capacity is 440 GB.
1. Calculate the number of shredding operations.

Volume Shredder operations 2–5
Hitachi Virtual Storage Platform G1000 Hitachi Volume Shredder User Guide
[(400 × 3) × 2] / 440 = 5.45 = six times
Round up the value (5.45) to the nearest whole number. You need to
overwrite the data six times.
2. Define the shredding settings.
Refer to Defining shredding conditions on page 2-6, enter the dummy
data 00 in the text box and add a row to the Data Pattern (User
Setting) list (add rows for performing the shredding operation six
times).
3. Erase the volume data.
Refer to Defining shredding conditions on page 2-6 and execute the
shredding operation.
4. Repeat steps 2 and 3 using the dummy data FF.
5. Repeat steps 2 and 3 using the dummy data 00.
For more information, see the Top window when selecting Logical Device
section in the Hitachi Virtual Storage Platform G1000 Provisioning Guide for
Open Systems.
Calculating the number of overwrite passes for FMDs
Because of the way space is allocated in FMDs, the dummy data that is used
to overwrite the volume must exceed the capacity of the target volume.
Therefore, before you shred a volume on FMDs, you need to calculate the
number of times the system must overwrite the volume with dummy data.
You must have the Storage Administrator (Provisioning) role to perform this
task.
1. Select an LDEV on the LDEVs tab in the Logical Devices window, and
write down its capacity and the amount of data in the RAID
configuration.
Examples amounts of data in a RAID configuration:
n of RAID5(nxD + 1P)
n of RAID6(nxD + 2P)
2. Use the following formula to calculate the number of times to overwrite
the data (N):
N = (User-capacity-for-Data x 2) / Capacity-of-target-volume
When the capacity of the FMD is 1,600 GB, 1,600GB x n
Example: The capacity of the FMD is 1,600 GB, the RAID configuration is
3D+1P, and the LDEV capacity is 880 GB.
[(1,600 x 3) x 2] / 880 = 10.9 = 11 times
Round up the value (10.9) to the nearest whole number. You need to
overwrite the data 11 times.
You can write dummy data up to eight times in one shredding operation. To
write dummy data nine or more times, perform the shredding operation for
the volume as many times as required.

Hitachi Virtual Storage Platform G1000 Hitachi Volume Shredder User Guide
2–6 Volume Shredder operations
Example of shredding data on FMDs
This example assumes that the capacity of the FMD is 1,600 GB, the RAID
configuration is 3D+1P, and the LDEV capacity is 880 GB.
1. Calculate the number of times to overwrite the data:
[(1,600 x 3) x 2] / 880 = 10.9 = 11 times
Round up the value (10.9) to the nearest whole number. You need to
overwrite the data 11 times.
2. Define the shredding settings.
Refer to Defining shredding conditions on page 2-6, select the Data
Pattern (User Setting) list and Random Data, then click Add eight
times.
3. Erase the volume data.
Refer to Defining shredding conditions on page 2-6 for procedures on
erasing the volume data.
4. Repeat steps 2 and 3, three more times, clicking Add three times.
Defining shredding conditions
Configure data overwrite patterns and the number of overwrite passes in
the Shredding Data Pattern window. By default the number of overwrite
passes is three; but you can change this number from three to up to eight
times. The system keeps user-specified settings while the Shred LDEVs
window is open.
You must have the Storage Administrator (Provisioning) role to perform this
task.
1. Open the Shred LDEVs window:
In Hitachi Command Suite:
a. On the Resources tab, click Storage Systems, and then expand
All Storage Systems.
b. Expand the target storage system, right-click Volumes, and then
select System GUI.
In Device Manager - Storage Navigator (mainframe-only environments):
In the Storage Systems tree, select Logical Devices to display the
LDEVs tab.
2. Select a blocked volume, click More Actions, and then select Shred
LDEVs to open the Shred LDEVs window.
3. Click Edit Data Pattern.
The Edit Shredding Data Pattern window opens.
4. To use the default pattern, click Default Pattern (00-FF-00).
To specify custom settings, click Data Pattern (User Setting) and
specify the data pattern as follows:
Caution: For FMDs, make sure you select Random Data as the
specified Data Pattern.