Configuration: Disk Groups and Virtual Disks 107
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Configuration: Disk Groups and 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. The maximum
number of physical disks supported in a disk group is 30. 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 capa city of an existing disk group. 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.
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