proavio RS16FS User Manual page 7

RS16 FS – Manual v.6.1A
Logical Unit Number. A logical unit number (LUN) is a unique
LUN
identifier which enables it to differentiate among separate
devices (each one is a logical unit).
GUI Graphic User Interface.
RAID width, copy and row are used to describe one RG.
RAID width,
RAID copy,
E.g.:
RAID row
(RAID cell in
one row)
Write-Through cache-write policy. A caching technique in
WT
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.
Write-Back cache-write policy. A caching technique in which
WB
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.
Set the volume to be Read-Only.
RO
Dedicated Spare disks. The spare disks are only used by one
DS
specific RG. Others could not use these dedicated spare disks
for any rebuilding purpose.
Global Spare disks. GS is shared for rebuilding purpose. If
GS
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.
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.
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