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Appendix B
Disk States - Virtual and Physical Disks The following tables indicate the statuses that can appear at the PERC
Virtual Disk Management utility.
RAID 5 (striping with
parity)
Stripes data, as well as parity,
across all physical disks in the
virtual disk. Parity
information is interspersed
across the virtual disk.
In the event of a single
physical disk failure, parity
data exists on the remaining
physical disks, which can be
used to restore the data to a
new, replacement physical
disk.
• Offers exceptional read
performance, as well as
redundancy.
• Requires only one extra
physical disk to offer
redundancy.
• For most systems with three
or more physical disks this is
the best choice as a RAID
level.
Table B-2. Physical Disk States
State Definition
ATAPI Indicates a peripheral device (CD-ROM, DVD, o r tape drive ) instead
of a physical disk. An ATAPI device cannot be initialized or added to
a virtual disk.
Non-Raid A physical disk has been moved from another, non-PERC S100
controller or non-PERC S300 controller.
Online The physical disk has been initialized and is part of a virtual disk.
Ready The physical disk has been initialized but is not currently used in a
virtual disk.
Failed A failed physical disk appears as Fai led only when (a) Vie w Virt ual
Disk Details is selected, and (b) the virtual disk to which the physical
disk belongs is selected. The Failed status is reported only when the
physical disk is part of a virtual disk.
Spare A physical disk that is assigned as a dedicated or global hot spare.
Table B-1. RAID Levels and Characteristics
(continued)
RAID Level Main Characteristics Advantages
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