User manual

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1.2 Terminology
The document uses the following terms:
RAID
RAID is the abbreviation of “Redundant Array of Independent
Disks”. There are different RAID levels with different degree
of the 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.
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:
Caution
Snapshot / rollback features need 512MB RAM or more.
Please refer to RAM certification list in Appendix A for more
detail.