S-ATA RAID Configuration
Page 5-1
Section 5
S-ATA RAID CONFIGURATION
Introduction
This section gives a brief introduction on the RAID-related background knowledge
and a brief introduction on S-ATA RAID Host Controller.
RAID Basics
RAID (Redundant Array of Independent Disks) is a method of combining two hard
disk drives into one logical unit. The advantage of an Array is to provide better
performance or data fault tolerance. Fault tolerance is achieved through data
redundant operation, where if one drives fails, a mirrored copy of the data can be
found on another drive. This can prevent data loss if the operating system fails or
hangs. The individual disk drives in an array are called “members”. The configura-
tion information of each member is recorded in the “reserved sector” that identifies
the drive as a member. All disk members in a formed disk array are recognized as a
single physical drive to the operating system.
Hard disk drives can be combined together through a few different methods. The
different methods are referred to as different RAID levels. Different RAID levels
represent different performance levels, security levels and implementation costs.
The table below briefly introduced these RAID levels.
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