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PD
The Physical Disk belongs to the member disk of one specific RAID group.
RD
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.
CV
Cache Volume. Controller uses onboard memory as cache. All RAM (except for
the part which is occupied by the controller) can be used as cache.
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 width,
RAID copy,
RAID row
(RAID cell in
one row)
RAID width, copy and row are used to describe one RG.
E.g.:
1.
One 4-disk RAID 0 volume: RAID width= 4; RAID copy=1; RAID
row=1.
2.
One 3-way mirroring volume: RAID width=1; RAID copy=3; RAID
row=1.
3.
One RAID 10 volume over 3 4-disk RAID 1 volume: RAID width=1;
RAID copy=4; RAID row=3.
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 media occurs at a later time. It speeds up system write performance but
needs to bear the risk where data may be inconsistent between data cache and
the physical disks in one short time interval.
RO
Set the volume to be Read-Only.
DS
Dedicated Spare disks. The spare disks are only used by one specific RG. Others
could not use these dedicated spare disks for any rebuilding purpose.
GS
Global Spare disks. GS is shared for rebuilding purpose. If some RGs need to use
the global spare disks for rebuilding, they could get the spare disks out from the
common spare disks pool for such requirement.
DC Dedicated
Cache.
GC Global
Cache.
