Avago Technologies MegaRAID SATA 150-4 (523) - Manual (Page 23)

MegaRAID Configuration Software User’s Guide 2-1
Copyright © 2003–2006 by LSI Logic Corporation. All rights reserved.
Chapter 2
Introduction to RAID
This chapter describes RAID features and the advantages that RAID
systems offer in terms of fault tolerance, improved I/O performance, and
data storage reliability. In addition, it discusses RAID configuration
strategies and planning.
This chapter consists of the following sections:
•
Section 2.1, “RAID Description”
•
Section 2.2, “RAID Benefits”
•
Section 2.3, “RAID Functions”
•
Section 2.4, “RAID Components and Features”
•
Section 2.5, “RAID Levels”
•
Section 2.6, “RAID Configuration Strategies”
•
Section 2.7, “RAID Availability”
•
Section 2.8, “RAID Configuration Planning”
2.1 RAID Description
RAID is an array of multiple independent hard disk drives that provides
high performance and fault tolerance. The RAID array appears to the
host computer as a single storage unit or as multiple logical units. Data
throughput improves because several disks can be accessed
simultaneously. RAID systems also improve data storage availability and
fault tolerance. Data loss caused by a hard drive failure can be recovered
by rebuilding missing data from the remaining data or parity drives.