Logic MegaRAID Express User's Guide

Table Of Contents
Chapter 5 Configuring MegaRAID Express 500
47
Array Configuration Planner
Using the Array Configuration Planner
The following table lists the possible RAID levels, fault
tolerance, and effective capacity for all possible drive configurations for an array
consisting of one to seven 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 physical drives. RAID 3 and RAID 5 require at least three drives. RAID 10
requires at least four drives, while RAID 30 and RAID 50 require at least six drives.
Number of
Drives
Possible
RAID Levels
Relative
Performance
Fault
Tolerance
Effective
Capacity
1 None Excellent No 100%
1 RAID 0 Excellent No 100%
2 None Excellent No 100%
2 RAID 0 Excellent No 100%
2 RAID 1 Good Yes 50%
3 None Excellent No 100%
3 RAID 0 Excellent No 100%
3 RAID 3 Good Yes 67%
3 RAID 5 Good Yes 67%
4 None Excellent No 100%
4 RAID 0 Excellent No 100%
4 RAID 3 Good Yes 75%
4 RAID 5 Good Yes 75%
4 RAID 10 Good Yes 50%
5 None Excellent No 100%
5 RAID 0 Excellent No 100%
5 RAID 3 Good Yes 80%
5 RAID 5 Good Yes 80%
6 None Excellent No 100%
6 RAID 0 Excellent No 100%
6 RAID 3 Good Yes 83%
6 RAID 5 Good Yes 83%
6 RAID 10 Good Yes 50%
6 RAID 30 Good Yes 67%
6 RAID 50 Good Yes 67%
7 None Excellent No 100%
7 RAID 0 Excellent No 100%
7 RAID 3 Good Yes 86%
7 RAID 5 Good Yes 86%
8 None Excellent No 100%
8 RAID 0 Excellent No 100%
8 RAID 3 Good Yes 87%
8 RAID 5 Good Yes 87%
8 RAID 10 Good Yes 50%
8 RAID 30 Good Yes 75%
8 RAID 50 Good Yes 75%