User manual

iSCSI GbE to SAS/SATA II RAID Subsystem

User Manual

1.4 Volume Relationship Diagram

This is the design of volume structure of the iSCSI RAID subsystem. It describes the

relationship of RAID components. One RG (RAID Group) is composed of several PDs

(Physical Disks). One RG owns one RAID level attribute. Each RG can be divided into

several VDs (Virtual Disks). The VDs in one RG share the same RAID level, but may have

different volume capacity. Each VD will be associated with the Global Cache Volume to

execute the data transaction. LUN (Logical Unit Number) is a unique identifier, in which

users can access through SCSI commands.