Adaptec MAN-00005-UG, Инструкция по установке и эксплуатации

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B.6.1 Array Configuration Table: Overview
Consider these points when using the tables:
To determine the approximate capacity of a particular configuration, assume that each physical disk has a unit capacity
of one. The value in the Effective Capacity column will indicate the effective available capacity for a Drive Group with
a given RAID level.
A configuration, is fault-tolerant or has enhanced availability, if there is an asterisk after the value in the Effective
Capacity column. The number of asterisks is proportional to the level of fault-tolerance, or availability, that a
configuration will exhibit. The more asterisks, the better the fault tolerance.
To determine the performance of a given configuration, correlate the configuration’s RAID level with the application.
See CAP Strategies.
Drives that are not affiliated with a Drive Group are assumed to be hot spare, or standby drives, and provide an
additional measure of fault-tolerance. The use of Standby drives with redundant RAID levels are indicated in the
Possible RAID Levels column as SBY.
In most of the configurations, multiple RAID levels can exist for a given Drive Group. These multiple RAID levels can
be implemented in the same Drive Group on different System Drives. A System Drive can be any percentage of a Drive
Group. If different RAID levels are configured for a single Drive Group, then the effective capacity will be different
than the value shown in the table. This is because the table does not consider the mixing of RAID levels within a Drive
Group.
The maximum number of logical drives that can be created is 32.
B.6.2 Array Configuration Tables
The following tables (One Drive, Two Drives, Three Drives, Four Drives, Five Drives, Six Drives, Seven Drives, Eight
Drives) give drives and drive groups, possible RAID levels for these drives or drive groups, and the effective capacity
for these drives or drive groups. See also Example RAID configurations. For example:
For One Drive: If you have one drive, you would have one drive group (A:o), a JBOD RAID level (A:JBOD), and an
effective capacity of 1 drive (A:1).
For Two Drives: If you have two drives, you could have two drive groups (A:o, B:o), both are JBODs (A:JBOD,
B:JBOD), each with an effective capacity of 1 drive (A:1, B:1). Or, you could have one drive group
(A:oo), a RAID 0 level (A:0), with an effective capacity of 2 drives (A:2). Or, you could have one
drive group (A:oo), a RAID 1 level (A:1), with an effective capacity of 1 drive with fault tolerance
(A:1*).
For Five Drives: If you have five drives, you could have five drive groups (A, B, C, D, E), all are JBODs, each with an
effective capacity of 1 drive. Or, you could have one drive group (A), a RAID 5 level with a standby
drive (spare), with an effective capacity of 3 drives with double the amount of fault tolerance. Or, you
could have two drive groups (A, B), where drive group A is a RAID 0 with an effective capacity of 2
drives; drive group B is a RAID 0+1 with a standby drive (spare) and an effective capacity of 1 drive
with double fault tolerance. Or, you could have one drive group (A): as a RAID 5, with a 4 drive
effective capacity and fault tolerance; as a RAID 0+1, with a 2.5 drive effective capacity and fault
tolerance; or as a RAID 0, with a 5 drive effective capacity.
Array Configuration: One Drive
Drives and Drive Groups Possible RAID Levels Effective Capacity
Table 6 Array configuration – One drive