RAID CONFIGURATION
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What kinds of hardware and software you need here:
1. A floppy drive.
2. A CD-ROM drive.
3. Several SATA hard disks.
4. A RAID driver diskette.
5. A motherboard driver CD.
6. Windows XP or Windows 7 Install CD.
Steps to install a new Windows XP (Windows 7) in a brand new RAID system:
1. Follow 5-3 to install SATA hard disks.
2. Follow 5-4 to create a RAID driver diskette.
(Windows 7 has in-box driver by its own and can skip this step).
3. Follow 5-5 to set BIOS setting “SATA Mode” to RAID or AHCI.
4. Follow 5-6 to create RAID in BIOS.
5. Follow 5-7 to Install Windows Operating System.
5-1 RAID Configuration Introduction
RAID (Redundant Array of Independent Disks) is a method for computer data storage schemes
that divide and/or replicate data among multiple hard drives. RAID can be designed to provide
increased data reliability (fault tolerance) or increased I/O (input/output) performance, or both.
The motherboard comes with the Intel® PCH. The following RAID configurations are provided
for users.
There are three major key concepts in RAID:
1. Mirroring : The copying of data to more than one disk;
2. Striping : The splitting of data across more than one disk;
3. Error correction : Where redundant data is stored to allow problems to be detected and
possibly fixed (known as fault tolerance).
Different RAID levels use one or more of these techniques, depending on the system require-
ments. The main aims of using RAID are to improve reliability, important for protecting informa-
tion that is critical to a business, for example a database of customer orders; or where speed is
important, for example a system that delivers video on demand TV programs to many viewers.
The configuration affects reliability and performance in different ways. The problem with using
more disks is that it is more likely that one will go wrong, but by using error checking the
total system can be made more reliable by being able to survive and repair the failure. Basic
mirroring can speed up reading data as a system can read different data from both the disks,
but it may be slow for writing if it insists that both disks must confirm that the data is correctly
written. Striping is often used for performance, where it allows sequences of data to be read
off multiple disks at the same time. Error checking typically will slow the system down as data
needs to be read from several places and compared. The design of RAID systems is there-
fore a compromise and understanding the requirements of a system is important. Modern disk
arrays typically provide the facility to select the appropriate RAID configuration.
RAID is often used in high availability systems, where it is important that the system keeps
running as much of the time as possible.
