Intermix Configurations; Raid-Level Intermix - Hitachi Universal Storage Platform V Reference Manual

Intermix Configurations

RAID-Level Intermix

RAID technology provides full fault-tolerance capability for the data drives of
the Universal Storage Platform V/VM. The cache management algorithms
enable the USP V/VM to stage up to one full RAID stripe of data into cache
ahead of the current access to allow subsequent access to be satisfied from
cache at host channel transfer speeds.
The Universal Storage Platform V/VM supports RAID-1+0 (RAID-10), RAID-5,
RAID-6, and intermixed RAID-level configurations, including intermixed array
groups within an array domain.
levels. All types of array groups (RAID-5 3D+1P, 7D+1P; RAID-10 2D+2D,
4D+4D; RAID-6 6D+2P) can be intermixed under one BED pair.
1st, 3rd
5th or 7th
BED Pair
2nd, 4th
6th or 8th
BED Pair
Figure 2-8
2-16
Hitachi Universal Storage Platform V/VM User and Reference Guide
RAID group
(2D+2D)
00
0
BED
1
(CL1)
2 00
3
0
00
BED
1
(CL2)
2
3
00
00
0
BED
1
(CL2)
2
00
3
0
BED
1
00
(CL1)
2
3
00
RAID group
(3D+1P)
Sample RAID Level Intermix
Architecture and Components
Figure 2-8 illustrates an intermix of RAID
RAID group
(3D+1P)
(7D+1P/6D+2P)
01 02 03
01 02 03
01 02 03
01 02 03
01 02 03
01 02 03
01 02 03
01 02 03
RAID group RAID group
(4D+4D) (4D+4D)
RAID group
46 47
46 47
46 47
46 47
46 47
46 47
46 47
46 47