Adaptec 2074700-R - ICP Vortex GDT8514RZ RAID Controller, Руководство пользователя

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20 Software Installation and User’s Guide
Introduction
Figure 1-6. RAID 10 - Combination of RAID 1 and RAID 0
1.3.6 Levels of Drive Hierarchy Within the ICP RAID Firmware
The ICP RAID firmware is based on four fundamental levels of hierarchy. Each level has
its “own drives” (components). The basic rule is to build up a “drive” on a given level of
hierarchy. The “drives” of the next lower level of hierarchy are used as components.
1.3.6.1 Level 1
Physical drives are hard disks and removable hard disks. Some Magneto Optical (MO)
drives are located on the lowest level. Physical drives are the basic components of all
“drive constructions”. However, before they can be used by the firmware, these hard disks
must be “prepared” through a procedure called initialization. During this initialization
each hard disk receives information which allows an univocal identification even if the
SCSI ID or the controller is changed. For reasons of data coherency, this information is
extremely important for any drive construction consisting of more than one physical drive.
1.3.6.2 Level 2
On the next higher level are the logical drives . Logical drives are introduced to obtain full
independence of the physical coordinates of a physical device. This is necessary to easily
change the ICP RAID controller and the channels, IDs, without loosing the data and the
information on a specific disk array.
1.3.6.3 Level 3
On this level of hierarchy, the firmware forms the array drives . Depending on the
firmware installed an array drive can be: