Configuring And Managing Raid; Raid Levels; Status And Color Definitions; Descriptions Of Raid Levels - HP StorageWorks P4000 User Manual

• Disk Health
Table 9 Status and color definitions
Status
Normal
Inactive
Uninitialized
Rebuilding
Off or Removed
Marginal
Faulty
Hot Spare
Hot Spare Down

Configuring and managing RAID

Managing the RAID settings of a storage system includes:
• Choosing the right RAID configuration for your storage needs
• Setting or changing the RAID configuration, if necessary
• Setting the rate for rebuilding RAID
• Monitoring the RAID status for the storage system
• Reconfiguring RAID when necessary

RAID Levels

The availability of certain RAID levels is determined by the number of storage system hard drives.
Table 10 Descriptions of RAID levels
RAID level
RAID 0 – Strip-
ing (No Fault
Tolerance)
RAID 1 – Mirror-
ing
54 Storage Configuration: Disk RAID and Disk Management
Description
Offers the greatest capacity and performance without data protection. If you select this
option, you will experience data loss if a hard drive that holds the data fails. However,
because no logical drive capacity is used for redundant data, this method offers the best
capacity. This method offers the best processing speed by reading two stripes on different
hard drives at the same time and by not having a parity drive.
Offers a good combination of data protection and performance. RAID 1 or drive mirroring
creates fault tolerance by storing duplicate sets of data on a minimum of two hard drives.
There must be an even number of drives for RAID 1. RAID 1 and RAID 1+0(10) are the
most costly fault tolerance methods because they require 50 percent of the drive capacity
to store the redundant data. RAID 1 mirrors the contents of one hard drive in the array onto
another. If either hard drive fails, the other hard drive provides a backup copy of the files
and normal system operations are not interrupted.
Color
Green
Yellow / orange
Yellow
Blue
Red
Yellow
Red
Green
Yellow