easyRAID S4-FWTT, Руководство пользователя

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Chapter 2 – Before you begin
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What else you need
In order to setup a working system, the following user-supplied items are required:
z Host computer system with IEEE 1394 or USB interface (IEEE 1394 and USB
host interface version)
z Four disk drives
For non-proprietary accessories, such as cables, etc., ask your vendor to
recommend compatible and reliable brands.
The hard drives in a RAID should match in size and speed. All drives in any
array should be identical models with the same firmware versions. RAIDs can
use any size drive,
however the smallest drive will determine the size of the
array.
Pre-installation planning
Introduction to RAID levels
The can support the following RAID levels: 0, 0+1 and 5 with the additional option of
RAID 5 + hot spare. Which is the right level for you? The answer depends on the
application it is used for.
RAID Level 0 offers high transfer rates, and is ideal for large blocks of data where speed
is of importance. Computer Aided Design, Graphics, Scientific Computing, Image and
Multimedia applications are all good examples. If one drive in a RAID 0 array fails
however, the data on the whole array is lost.
RAID Level 0+1 combines mirroring and striping functions on a minimum of four hard
disks. Mirroring provides full redundancy and protects data in case of multiple drive
failure (providing that data on one of each mirrored pair of drives is intact).
RAID Level 5 arrays offer high I/O transaction rates, and are the ideal choice when used
with on-line transaction processing applications, such as those used in banks, insurance
companies, hospitals, and all manner of office environments. These applications typically
perform large numbers of concurrent requests, each of which makes a small number of
disk accesses. If one drive in a RAID 5 array fails, the lost data can be rebuilt from data
on the functioning disks. The allows users to set one disk as a
hot spare that will be
activated automatically to replace a failed disk.