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Foxconn A79A-S User Manual

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5

RAID 0 (Striped)

RAID 0 reads and writes sectors of data interleaved among multiple drives. If any disk

member fails, it affects the entire array. The disk array data capacity is equal to the

number of drive members times the capacity of the smallest member. RAID 0 does

not support fault tolerance.

RAID 1 (Mirror)

RAID 1 writes duplicate data onto a pair of drives and reads both sets of data in

parallel. If one of the mirrored drives suffers a mechanical failure or does not respond,

the remaining drive will continue to function. Due to redundancy, the drive capacity of

the array is the capacity of the smallest drive.

RAID Ready

A "RAID Ready" system is a specific system configuration that, with the addition of

a second Serial ATA hard drive, can be seamlessly migrated to a configuration that

provides either improved storage performance or data protection from a single hard

drive failure.

RAID 5 (Parity)

RAID 5 provides data striping at the byte level and also stripes error correction infor-

mation. This results in excellent performance and good fault tolerance. Level 5 is one

of the most popular implementations of RAID.

RAID 10 (Striped Mirror)

RAID 10 is a combination of striping and mirroring. This configuration provides optimal

speed and reliability, but you need four SATA hard disks.

Span (JboD)

JBOD stands for “Just a Bunch of Disks”. Each drive is accessed as if it were on a

standard SCSI host bus adapter. This is useful when a single drive configuration is

needed, but it offers no speed improvement or fault tolerance. A spanned volume is a

formatted partition which data is stored on more than one hard disk, yet appears as

one volume. Unlike RAID, spanned volumes have no fault-tolerance, so if any disk

fails, the data on the whole volume could be lost. Additionally, the system or boot

partitions cannot be included in a spanned volume. FAT16/32 and NTFS file systems

may be used, and the volume can span up to 32 hard disks.

Comparison Table :

Solution

Hard Disks No.

Capacity

Performance

Reliability

Application

RAID0

>=2

All

Highest

Dangerous

Look for speed

RAID1

2

50%

Read faster

Excellent

100% Data backup

RAID5

>=3

Smallest*(N-1)

Read faster

Write slower

Good

Limited budget

RAID10

>=4 (Even number)

Smallest*2

High

Excellent

Unlimited budget

Span

>=1

All

none

Dangerous

Big disk space