Lenovo ThinkServer RD240 MegaRAID SAS Software User Guide - Page 33

Introduction to RAID, 2.1 RAID Description, 2.2 RAID Benefits, 2.3 RAID Functions

Page 33 highlights

Chapter 2 Introduction to RAID This chapter describes RAID (Redundant Array of Independent Disks), RAID functions and benefits, RAID components, RAID levels, and configuration strategies. In addition, it defines the RAID availability concept, and offers tips for configuration planning. 2.1 RAID Description RAID is an array, or group of multiple independent physical drives that provide high performance and fault tolerance. A RAID drive group improves I/O (input/output) performance and reliability. The RAID drive group appears to the host computer as a single storage unit or as multiple virtual units. I/O is expedited because several drives can be accessed simultaneously. 2.2 RAID Benefits RAID drive groups improve data storage reliability and fault tolerance compared to single-drive storage systems. Data loss resulting from a drive failure can be prevented by reconstructing missing data from the remaining drives. RAID has gained popularity because it improves I/O performance and increases storage subsystem reliability. 2.3 RAID Functions Virtual drives are drive groups or spanned drive groups that are available to the operating system. The storage space in a virtual drive is spread across all of the drives in the drive group. MegaRAID SAS Software User Guide 2-1

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MegaRAID SAS Software User
Guide
2-1
Chapter 2
Introduction to RAID
This chapter describes RAID (Redundant Array of Independent Disks),
RAID functions and benefits, RAID components, RAID levels, and
configuration strategies. In addition, it defines the RAID availability
concept, and offers tips for configuration planning.
2.1
RAID Description
RAID is an array, or group of multiple independent physical drives that
provide high performance and fault tolerance. A RAID drive group
improves I/O (input/output) performance and reliability. The RAID drive
group appears to the host computer as a single storage unit or as
multiple virtual units. I/O is expedited because several drives can be
accessed simultaneously.
2.2
RAID Benefits
RAID drive groups improve data storage reliability and fault tolerance
compared to single-drive storage systems. Data loss resulting from a
drive failure can be prevented by reconstructing missing data from the
remaining drives. RAID has gained popularity because it improves I/O
performance and increases storage subsystem reliability.
2.3
RAID Functions
Virtual drives are drive groups or spanned drive groups that are available
to the operating system. The storage space in a virtual drive is spread
across all of the drives in the drive group.