Basic Raid Types; Raid 0 With Two Hard Drives (Striped) - Compaq dc5750 - Microtower PC User Manual

NOTE: The following notes are important for RAID configuration:
• RAID 1 is the only RAID configuration that HP Compaq dc5750 Business PC products offer
as factory configurations.
• The preconfigured systems:
- Are complete RAID systems.
- Have both drives installed.
- Have the necessary Option ROM configuration.
- Are preloaded and preinstalled with all required software.
- Include a preinstalled operating system that is mirrored mode out of the box.

Basic RAID Types

This section provides a brief explanation of the supported RAID configurations for HP Compaq dc5750
Business PCs.

RAID 0 with two hard drives (Striped)

Even though HP supports RAID 0, it is not the recommended configuration for business PC users. Lack of
redundancy causes less than half the reliability of a single hard drive system since the Mean Time
Between Failure (MTBF) of RAID 0 is equal to the MTBF of an individual drive, divided by the number of
drives.
RAID 0 with two hard drives (Striped)
Table 3
First Disk
Data Segment 1
Data Segment 3
Data Segment 5
Data Segment 7
Data Segment 9
Data Segment 1 1
Data Segment 13
Data Segment 15
In the previous table, each "Data Segment n" represents a group of data, known as a strip. In this case,
each row represents a stripe. RAID 0 represented in the table above shows how information is segmented,
made into chunks or strips, and stored across the stripes of the hard drive members of this RAID volume.
To better illustrate the concept of RAID 0 and striping, the following graphic shows how a sequence of
data "ABCD..." is stored in a RAID 0 mode. In this example, each letter represents a segment or strip. The
graphic shows how the various pieces of the information go to different hard drives. If any segment of
RAID 0 fails, all information from all members is lost.
Second Disk
Data Segment 2
Data Segment 4
Data Segment 6
Data Segment 8
Data Segment 10
Data Segment 12
Data Segment 14
Data Segment 16
4