Using The Array Configuration Planner; Table 7-12. Array Configuration Planner - Dell PowerEdge Expandable RAID Controller 3 User Manual

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Confi gur ing PERC 3

Using the Array Configuration Planner

Table 7-12 lists RAID levels, fault tolerance, and effective capacity for some
possible drive configurations for an array consisting of one to 32 drives. This
table does not take into account any hot spare (standby) drives. You should
always have a hot spare drive in case of drive failure. RAID 1 requires two
drives. RAID 5 requires at least three drives. RAID 10 requires at least four
drives. RAID 50 requires at least six drives.
Ta b l e 7 - 1 2 . A r r a y C o n f i g u r a t i o n P l a n n e r
Number Possible RAID
of Drives Levels
1 RAID 0
2 RAID 0
2 RAID 1
3 RAID 0
3 RAID 5
4 RAID 0
4 RAID 5
4 RAID 10
5 RAID 0
5 RAID 5
6 RAID 0
6 RAID 5
6 RAID 10
(spanned)
6 RAID 50
(spanned)
7 RAID 0
7 RAID 5
8 RAID 0
8 RAID 5
8 RAID 10
(spanned)
Relative Fault
Performance Tolerance
Excellent No
Excellent No
Good Yes
Excellent No
Good Yes
Excellent No
Good Yes
Good Yes
Excellent No
Good Yes
Excellent No
Good Yes
Excellent Yes
Good Yes
Excellent No
Good Yes
Excellent No
Good Yes
Excellent Yes
Effective
Capacity
100%
100%
50%
100%
67%
100%
75%
50%
100%
80%
100%
83%
50%
67%
100%
86%
100%
87%
50%