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Copyright@2004~2014 Qsan Technology, Inc. All Rights Reserved.
Qsan Document – User Manual
RAID 6
2-dimensional parity protection over the member disks.
4
RAID 0+1
Mirroring of the member RAID 0 volumes.
4
RAID 10
Striping over the member RAID 1 volumes.
4
RAID 30
Striping over the member RAID 3 volumes.
6
RAID 50
Striping over the member RAID 5 volumes.
6
RAID 60
Striping over the member RAID 6 volumes.
8
JBOD
The abbreviation of
Just a Bunch Of Disks
. Independently
address a drive.
1
Volume Relationship
The following graphic is the volume structure which Qsan has designed. It describes the
relationship of RAID components.
One RG (RAID group) consists of a set of VDs (Virtual Disk) and owns one RAID level attribute. Each
RG can be divided into several VDs. The VDs in one RG share the same RAID level, but may have
different volume capacity. All VDs share the CV (Cache Volume) to execute the data transaction.
LUN (Logical Unit Number) is a unique identifier, in which users can access through SCSI
commands.
Fibre Channel Concepts
Fibre channel started use primarily in the supercomputer field, but has become the standard
connection type for storage area networks (SAN) in enterprise storage.
RG
PD 2
PD 3
DS
PD 1
VD 1
VD 2
QSnap
VD
RAM
Cache Volume
+
+
LUN 1
LUN 2
LUN 3
+
+
+
+