HP XP P9500 Storage - Manual (Page 6)

2 Volume Shredder Process
To overwrite a volume, block the volume, configure the shred settings, and then run the application.
You can view the results and stop the shredding process.
Volume Shredder workflow
Use the following workflow to overwrite a volume:
1. “Blocking volumes” (page 6)
2. “Calculating shredding passes for flash disks” (page 6)
3. “Shredding a volume” (page 7)
4. “Shredding a volume” (page 7)
5. “Viewing results from the Task window” (page 9)
You can also stop the shredding process. For more information, see “Stopping volume shredding”
(page 8) .
Blocking volumes
Before you can overwrite a volume, you must change the status of the volume to blocked.
NOTE: When a volume has a status of blocked, you cannot write to the volume.
1. Open the Remote Web Console main window.
2. Select Storage System in Explorer.
3. Select the volume (resource) under the Storage System folder.
The LDEVs tab appears when you select a parity group in Parity Group or when you select
an LDEV in Logical Device.
4. Check the volume status in the Status column.
If Block appears, calculate the shredding passes for flash disks. For more information, see
(page 6) .
5. Select the volume, and then click Block LDEVs.
6. When the confirmation message appears, click Apply.
Calculating shredding passes for flash disks
Before you overwrite a flash disk volume, calculate the number of times the system must overwrite
the volume with dummy data. Because of the way space is allocated in a flash disk, you must
overwrite data with dummy data that exceeds the capacity of the target volume.
1.
Select an LDEV in Logical Device and write down its capacity and the amount of data in the
RAID configuration (found on the LDEVs tab).
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 = (Capacity-of-target-volume + User-capacity-for-Data *1 ) / Capacity-of-target-volume
*1: User capacity for data.
When the capacity of the flash disk is 72 GB, 72 GB x n
Example: Flash disk is 72 GB, RAID configuration is 3D+1P, and LDEV is 100 GB
[(72 x 3) + 100] / 100 = 3.16
Round the value (3.16) to the nearest whole number. You need to overwrite the data four times.
6 Volume Shredder Process