Tandberg Data
Glossary
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Tandberg Viking FS-1600 Series NAS Hardware User Manual
RAID 1
RAID 1, also known as disk mirroring, writes data simultaneously to several
duplicate drives. If one drive fails, the other drive(s) continues to function as
a single drive until the failed drive is replaced.
RAID 5
RAID 5 is also known as striping with parity at byte level. In RAID 5, both
data and parity information are written to all of the drives in the subsystem. If
one drive in the system fails, the parity information can be used to
reconstruct the data from that drive. All drives in the array system can be
used for a seek operation at the same time, thereby increasing the
performance of the RAID system.
RAID 6
RAID 6 provides the highest reliability, but is not yet widely used. It is similar
to RAID 5, but it performs two different parity computations or the same
computation on overlapping subsets of data. RAID 6 can offer fault tolerance
greater than RAID 1 or RAID 5 but consumes the capacity of 2 disk drives
for distributed parity data. RAID 6 is an extension of RAID 5 but uses a
second, independent distributed parity scheme. Data is striped on a block
level across a set of drives, and then a second set of parity is calculated and
written across all of the drives.
RAID 10
RAID 10 is a combination of RAID 0 and RAID 1, striping and disk mirroring.
RAID Level 10 combines the fast performance of Level 0 with the data
redundancy of Level 1. In this configuration, data is distributed across
several drives, similar to Level 0. Then the data are duplicated to another set
of drives for data protection. RAID 10 provides the highest read/write
performance of any of the hybrid RAID levels.
RAID 0+1
RAID 0+1 is a mirrored array whose segments are RAID 0 arrays. It has the
same fault tolerance as RAID 5, and the same overhead for fault tolerance
as mirroring alone. This RAID has excellent performance, but not maximum
reliability.
Rack mount
Ordinarily, a 19-inch rack (cabinet) in which servers or drive units made to fit
such a rack are mounted. A rack mount kit is hardware, such as sliding rails,
for mounting devices in such a rack.
Router
