Technical information
June 2012 Dell EqualLogic Configuration Guide v13.2 21
2.4.4 RAID 50 Drive Layouts and Total Usable Storage
Table 11 shows the drive layouts that are enforced when using a RAID 50 policy based on the number
of drives in each array/hot spare configuration and the total usable storage available for each model.
RAID 50 (RAID 5 sets in a striped set) is created by first creating two or more RAID 5 sets and then
striping data over those RAID5 sets. RAID 50 implementations can tolerate a single drive failure per
RAID5 set.
Table 11 RAID 50 Drive Layouts and Total Storage Available with Hot Spares (in GB)
Disk Drives
Hot Spare
No Hot Spare
6
5 Data/Parity + 1 Hot-spare
N/A
(a)
7
6 Data/Parity + 1 Hot-spare
N/A
(a)
8
6 Data/Parity + 2 Hot-spares
8 data/parity
12
(d)
10 Data/Parity + 2 Hot-spares
12 data/parity
14
12 Data/Parity + 2 Hot-spares
14 data/parity
16
14 Data/Parity + 2 Hot-spares
16 data/parity
24
(d)
22 Data/Parity + 2 Hot-spares
24 data/parity
48
(b)
46 Data/Parity + 2 Hot-spares
N/A
(c)
(a)
RAID 50 requires an even number of disk drives. A 7 drive configuration without hot-spare would result in odd
number of disk drives.
(b) 48 drive arrays implement stripes across multiple RAID 5 sets within a single chassis.
(c) 48 drive arrays cannot implement a no hot-spare policy.
(d) PS4100/PS6100 models only
Total Usable Storage Available: All Models Prior to PS4100/PS6100
Disk
Drive
Qty /
Size
50
(a)
100
(a)
74 146 250 300 400 450 500 600 750 1000 2000 3000
7
(b)
- - - - 954 - - - - - - - - -
8
(c)
- - - - 954 - - - - - - - - -
14
(d)
- - 709 - 2388 - 3828 - 4789 - - - - -
16
572 1145 - 1681 2868 3444 4596 5173 5749 6901 8629 11510 - 35404
48
- - - - - - - - 19394 23275 - 38800 74367 115052
Total Usable Storage Available: PS4100/PS6100
Disk
Drive
Qty / Size
146 200
(e)
300
400
(e)
500 600 900 1000 2000 3000
6
- - - - 1913 2286 - 3826 7817 11819
12
1121 - 2286 3166 3826 4595 6904 7663 15646 23595
24
2628 3573 5167 7157 8631 10357 15547 17273 35140 53106
(a)
Solid State Disk
(b) Legacy PS50E
(c) PS4000E and PS6000E only
(d) Legacy PS70E,PS100E, PS100X, PS200E and PS300E
(e) PS6100S (SSD) only