Dell PS4000 - RAID 10 Implementation Details; Volume Attributes and Naming

Dell EqualLogic Configuration Guide v11.3
11
Disk Drive
Qty / Size
50
(a)
100
(a)
74
146
250
300
400
450
500
600
750
1000
2000
7
(b)
-
-
-
-
1000
-
-
-
-
-
-
-
-
8
(c)
-
-
-
-
1250
-
-
-
-
-
-
-
-
14
(d)
-
-
740
-
2500
-
4000
-
5000
-
-
-
-
16
650
1300
-
1898
3250
3900
5200
5850
6500
7800
9750
13000
-
8 / 8
(e)
-
-
-
-
-
-
-
2850
-
-
-
-
-
48
-
-
-
-
-
-
-
-
19500
23400
-
39000
78000
(a) Solid State Disk
(b) Legacy PS50E
(c) PS4000E and PS6000E only
(d) Legacy PS70E, PS100E, PS100X, PS200E, PS300E and PS400E
(e) PS60x0 XVS with 8 x 100GB SSD and 8 x 450GB SAS
Table 8: RAID 6 Total Storage Available with Hot Spares (in GB)
2.4.3 RAID 10
RAID 10 (mirrored sets in a striped set) combines two high performance RAID types: RAID 0 and RAID 1.
A RAID 10 is created by first building a series of two disk RAID 1 mirrored sets, and then distributing
data over those mirrors. RAID 10 implementations can tolerate one drive failure per mirror pair.
For EqualLogic arrays using a RAID 10 policy, Table 9 shows the drive layouts that are enforced based
on the number of drives in each array and the hot spare configuration.
Disk
Drives
Hot Spare
No Hot Spare
7
6 Data (3 mirrors)
1 Hot-spare
N/A
(a)
8
6 Data (3 mirrors)
2 Hot-spares
8 data (4 mirrors)
14
12 Data (6 mirrors)
2 Hot-spares
14 Data (7 mirrors)
16
14 Data (7 mirrors)
2 Hot-spares
16 Data (8 mirrors)
48
46 Data (23 mirrors)
2 Hot-spares
N/A
(b)
(a) Not supported. An even number of drives is required by RAID 10
(b) 48 drive arrays cannot implement a no hot-spare policy.
Table 9: RAID 10 Drive Layouts
For EqualLogic arrays using a RAID 10 policy, the total quantity of raw storage available can be
computed based on number of drives and the hot spare configuration. The Table 10 below shows the
amount of raw storage available using the hot spare drive layouts specified in Table 9 above.