HP XP Data Shredder Software - Manual (Page 7)

2 About Virtual LVI/LUN and Volume Shredder
This chapter provides an in-depth overview of Virtual LVI/LUN and Volume Shredder.
•
“Overview of Virtual LVI/LUN” (page 7)
•
“Overview of LDEV Formatting” (page 19)
•
“Overview of Quick Formatting” (page 20)
•
“Overview of Configuring External Mainframe Volumes” (page 20)
•
“Overview of Volume Shredder” (page 21)
Virtual LUN is a function for open systems. To use this function, you need the software called Open
Volume Management.
Virtual LVI is a function for mainframe systems. To use this function, you need the software called
Virtual LVI.
The shredding function is for both open and mainframe systems. To use this function, you need the
software called Volume Shredder.
The only difference between the Virtual LUN function and the Virtual LVI function is that the Virtual
LUN function is for open systems while the Virtual LVI function is for mainframe systems. Therefore,
in this manual, the Virtual LUN function and the Virtual LVI function are collectively referred to as
VLL.
In this manual, the term shredding refers to the process of deleting all data in a volume by
overwriting all data in the volume with dummy data.
Overview of Virtual LVI/LUN
This section describes the VLL function, configuration of VLL, and requirements of the storage
subsystem ID (SSID). The VLL operations include the following:
•
Viewing concatenated parity groups (see “Viewing Concatenated Parity Groups” (page 69) )
•
Converting a normal volume into free space (Volume to Space) (see “Converting Logical
Volumes to Space” (page 70) )
•
Defining and installing a VLL (customized) volume (Install CV) (see “Creating VLL Volumes
(Install CV Function)” (page 71) )
•
Deleting a VLL volume (see “Deleting VLL Volumes” (page 73) )
•
Initializing a VLL volume (Volume Initialize and Make Volume) (see “Converting CVs Back to
FVs (Volume Initialize Operation)” (page 74) and “Re-creating the CVs After Initializing the
VDEV (Make Volume Operation)” (page 76) )
Virtual LVI/LUN Functions
Virtual LVI/LUN (VLL) works on each virtual device (VDEV) that consists of a group of logical volumes
(LDEVs or LUs) in a parity group. Usually, one VDEV consists of some fixed volumes (FV) and some
free space. The number of fixed volumes is determined by the emulation type. A Virtual LVI/LUN
volume usually consists of at least one fixed volume (FV), one or more custom-sized volumes (CVs),
and some free space. VLL allows you to configure variable-size volumes, which are usually smaller
than normal (fixed-size) volumes. Therefore, if several frequently accessed files are located in the
same logical volume, access to some of these files can be delayed. To address this possible data
access problem, use VLL to split the logical volume into multiple volumes and scatter the files across
the multiple volumes. This can improve the data accessing performance. VLL can also be used to
divide logical volumes into smaller command devices and improve the efficiency of disk capacity.
Overview of Virtual LVI/LUN 7