Hard Drive Arrays; The Drive Array - Compaq RAID Array 4100 User Manual

E
Appendix

Hard Drive Arrays

The information in this appendix describes hard drive array concepts, data
protection methods, including fault-tolerance options, and data reliability
features of the Compaq RA4000 Controller installed in the Compaq
StorageWorks RAID Array 4100. Before configuring the RA4000 Controller,
review the following general information so that you will be familiar with the
terms and concepts required for configuration.

The Drive Array

A drive array is a collection of hard drives (physical drives) grouped together
to create an array of physical drives. An array is made up of one or more
subsets called logical drives (sometimes called logical volumes) that are
spread across all physical drives in the array. Operating systems view logical
drives as a single, contiguous storage space although it is made up of parts of
several physical drives.
The generic drive array illustrated in Figure E-1 consists of two logical drives
spread across three physical drives. Figure E-2 through Figure E-4 illustrates
other drive array configurations.