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ASUS GUI RAID Manager: Array Management
4.1
Background Information
4-3
4.1
Background Information
Redundant Arrays of Independent Disks (RAID) is a storage
technology used to improve the processing capability of storage
systems. This technology is designed to provide reliability in
disk array systems and to take advantage of the performance
gains multiple disks can offer.
RAID comes with a redundancy feature that ensures fault-
tolerant, uninterrupted disk storage operations. In the event of a
disk failure, disk access will still continue normally with the
failure transparent to the host system.
RAID has six levels: RAID 0 ~ 5. RAID levels 1, 3 and 5 are
the most commonly used levels, while RAID levels 2 and 4 are
the less popular ones.
Appendix C, RAID Levels, gives
information about these levels, including the benefits of each.
ASUS disk array controllers support hot-swapping where a failed
drive can be replaced while the disk array system continues to
function. Spares can also be assigned so that, as soon as a drive
fails, the spare will be automatically configured into the array
and reconstruction will commence.
4.1.1 Definition of Terms
This section describes some of the disk array terms used in this
documentation.
♦ Physical drives.
These are the actual SCSI drives
installed on the connectors of the SCSI cables.
These
drives are displayed on the Physical Drives window.
♦ Spare drives. These are physical drives that serve as
backups. When a drive fails, the spare is automatically
configured into the array, and data reconstruction will