Administrator Guide

Disk Groups, Standard Virtual Disks, And Thin

Virtual Disks

Creating Disk Groups And Virtual Disks

Disk groups are created in the unconfigured capacity of a storage array, and virtual disks are created in the free

capacity of a disk group or disk pool. The maximum number of physical disks supported in a disk group is 120 (192 with

the premium feature activated). The hosts attached to the storage array read and write data to the virtual disks.

NOTE: Before you can create virtual disks, you must first organize the physical disks into disk groups and configure

host access. Then you can create virtual disks within a disk group.

To create a virtual disk, use one of the following methods:

• Create a new disk group from unconfigured capacity. First define the RAID level and free capacity (available

storage space) for the disk group, and then define the parameters for the first virtual disk in the new disk group.

• Create a new virtual disk in the free capacity of an existing disk group or disk pool. You only need to specify the

parameters for the new virtual disk.

A disk group has a set amount of free capacity that is configured when the disk group is created. You can use that free

capacity to subdivide the disk group into one or more virtual disks.

You can create disk groups and virtual disks using:

• Automatic configuration — Provides the fastest method, but with limited configuration options

• Manual configuration — Provides more configuration options

When creating a virtual disk, consider the uses for that virtual disk, and select an appropriate capacity for those uses.

For example, if a disk group has a virtual disk that stores multimedia files (which tend to be large) and another virtual

disk that stores text files (which tend to be small), the multimedia file virtual disk requires more capacity than the text file

virtual disk.

A disk group should be organized according to its related tasks and subtasks. For example, if you create a disk group for

the Accounting Department, you can create virtual disks that match the different types of accounting performed in the

department: Accounts Receivable (AR), Accounts Payable (AP), internal billing, and so forth. In this scenario, the AR and

AP virtual disks probably need more capacity than the internal billing virtual disk.

NOTE: In Linux, the host must be rebooted after deleting virtual disks to reset the /dev entries.

NOTE: Before you can use a virtual disk, you must register the disk with the host systems. See Host-To-Virtual Disk

Mapping.

Creating Disk Groups

NOTE: If you have not created disk groups for a storage array, the Disk Pool Automatic Configuration Wizard is

displayed when you open the AMW. For more information on creating storage space from disk pools, see Disk

Pools.