Raid Introduction; Raid Functions; Raid Levels; Raid 0 - Inspur 3008 Series Configuration Manual

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RAID Introduction

This chapter introduces the basic concepts and features of RAID.
1.1

RAID Functions

RAID is the abbreviation of "Redundant Array of Independent Disk". Simply put,
RAID is a technology that combines multiple independent hard disks (physical hard
disks) in different ways to form a group of hard disks (logical hard disks), thus
providing higher storage performance than a single hard disk and providing data
backup. Depending on the different combinations of disk displays, RAID can be
classified into different RAID levels. With data backup, users can restore corrupted
data from the backup to ensure data security. In addition, users can manage the
drive group just like a single drive, and can also partition or format it. In brief,
operations on a RAID array are the same as those on a single drive. The only
difference lies in that a RAID array delivers a higher storage speed and enables
automatic data redundancy backup.
RAID supports:
Automatic detection of failed drives

Rebuilding of data in bad sectors

Drive backup

Hot-swap drives

Drive capacity expansion

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RAID Levels

Various RAID levels are available to provide different data access speeds, security
levels, and cost performances. Users can select appropriate RAID levels based on
their actual needs in terms of availabilities, performances, and capacities of
storage systems. The commonly used RAID levels include RAID 0, RAID 1, RAID 5,
RAID 6, RAID 10, RAID 1E, RAID 50, and RAID 60.

1.2.1 RAID 0

Also known as striping, RAID 0 divides data into multiple data blocks with the same
size and writes them into different drives in the array. With data distributed across
multiple drives, data read/write is performed concurrently on these drives.
Therefore, the capacity and data transfer rate of RAID 0 is theoretically N times of
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