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Quick Installation Guide
3. Support RAID Levels
RAID is an acronym for Redundant Array of Independent Disks. It is
an array of multiple independent hard disk drives that provides high
performance and fault tolerance. The ARC-1200 SATA RAID controlller
supports disk arrays using the following RAID levels:
3.1 RAID 0
RAID 0, also referred to as striping, writes stripes of data across
multiple disk drives instead of just one disk drive. RAID 0 does not
provide any data redundancy, but does offer the best high-speed data
throughput. RAID 0 breaks up data into smaller blocks and then writes
a block to each drive in the array. Disk striping enhances performance
because multiple drives are accessed simultaneously; the reliability of
RAID Level 0 is less because the entire array will fail if any one disk
drive fails, due to a lack of redundancy, the reliability of RAID Level 0
is less because the entire array will fail if any one disk drive fails.
3.2 RAID 1
RAID 1 is also known as “disk mirroring”; data written on one disk
drive is simultaneously written to another disk drive. Read performance
will be enhanced if the array controller can, in parallel, access both
members of a mirrored pair. During writes, there will be a minor
performance penalty when compared to writing to a single disk. If one
drive fails, all data (and software applications) are preserved on the
other drive. RAID 1 offers extremely high data reliability, but at the
cost of doubling the required data storage capacity. But at the cost of
doubling the required data storage capacity.
3.3 JBOD
(Just a Bunch Of Disks) A group of hard disks in a RAID controller are
not set up as any type of RAID configuration. All drives are available to
the operating system as an individual disk. JBOD does not provide data
redundancy.
