Arrays - Adaptec DuraStor 7220SS User Manual

Channel Number—Indicates to which channel (bus) on the
I
controller the SCSI drive is attached.
SCSI ID (also known as target ID)—Identifies the drive on the
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SCSI channel.
Logical Unit Number (LUN)—The number assigned to a
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subdevice (logical unit) of a SCSI device, which is usually zero
for a disk drive.
Note: If you are using an external controller, the host
computer addresses arrays via the controllers' ID and a
different LUN for each array.

Arrays

An array, also known as a container, is two or more physical disk
drives grouped together to appear as a single device (virtual drive)
to the user. A volume set created on a single disk drive is also
referred to as an array. You create arrays from the free space of one
or more partitions on one or more physical disk drives.
An array that spans multiple physical disk drives can be larger
than any one of the physical drives. An array's underlying
partitions can be smaller than a physical disk drive. Consequently,
if the controller allows, several arrays' partitions can reside on a
single physical disk drive.
The partitions that make up an array represent used (or allocated)
space on each disk drive. The used space is available to store data,
but cannot be allocated to another array.
Storage Concepts
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