Intel SRCU31, Руководство пользователя

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Introduction and General Information 19
Levels of Drive Hierarchy Within the Intel
®
RAID
Controller SRCU31 Firmware
The Intel RAID Controller SRCU31 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.
Level 1
Physical drives are hard disk drives and removable hard disk drives. 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 disk drives must be
“prepared” through a procedure called initialization. During this initialization each hard disk drive
receives information, which allows an unequivocal 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.
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 Intel RAID Controller SRCU31 and the channels, IDs, without loosing the data and the
information on a specific disk array.
Level 3
On this level of hierarchy, the firmware forms the array drives. Depending on the firmware
installed an array drive can be:
•
Single Disks: one disk or a JBOD (just a bunch of drives)
•
Chaining sets (concatenation of several hard disk drives)
•
RAID 0 array drives
•
RAID 1 array drives, RAID 1 array drives plus a hot fix drive
•
RAID 4 array drives, RAID 4 array drives plus a hot fix drive
•
RAID 5 array drives, RAID 5 array drives plus a hot fix drive
•
RAID 10 array drives, RAID 10 array drives plus a hot fix drive