User manual

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RAID drive obtains performance, capacity and reliability than a single drive. The
operating system detects the RAID drive as a single storage device.
1.2.1 Terminology
The document uses the following terms:
•
Part 1: Common
RAID
Redundant Array of Independent Disks. There are different
RAID levels with different degree of data protection, data
availability, and performance to host environment.
PD
The Physical Disk belongs to the member disk of one
specific RAID group.
RG
Raid Group. A collection of removable media. One RG
consists of a set of VDs and owns one RAID level
attribute.
VD
Virtual Disk. Each RD could be divided into several VDs.
The VDs from one RG have the same RAID level, but may
have different volume capacity.
LUN
Logical Unit Number. A logical unit number (LUN) is a
unique identifier which enables it to differentiate among
separate devices (each one is a logical unit).
GUI
Graphic User Interface.
RAID cell
When creating a RAID group with a compound RAID level, such as
10, 30, 50 and 60, this field indicates the number of subgroups in
the RAID group. For example, 8 disks can be grouped into a RAID
group of RAID 10 with 2 cells, 4 cells. In the 2-cell case, PD {0, 1,
2, 3} forms one RAID 1 subgroup and PD {4, 5, 6, 7} forms another
RAID 1 subgroup. In the 4-cells, the 4 subgroups are PD {0, 1}, PD
{2, 3}, PD {4, 5} and PD {6,7}.
WT
Write-Through cache-write policy. A caching technique in
which the completion of a write request is not signaled until
data is safely stored in non-volatile media. Each data is
synchronized in both data cache and accessed physical
disks.
WB
Write-Back cache-write policy. A caching technique in
which the completion of a write request is signaled as soon
as the data is in cache and actual writing to non-volatile
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