Introduction to RAID : Number of Drives

Number of Drives

Your configuration planning for the Nytro MegaRAID card depends in part on the number of drives that you want to use in a RAID drive group.

The number of drives in a drive group determines the RAID levels that can be supported. Only one RAID level can be assigned to each virtual drive.

Drive Group Purpose

Important factors to consider when creating RAID drive groups include availability, performance, and capacity. Define the major purpose of the drive group by answering questions related to these factors, such as the following, which are followed by suggested RAID levels for each situation:

*

Will this drive group increase the system storage capacity for general-purpose file and print servers?

Use RAID 5, 6, 10, 50, or 60.

*

Does this drive group support any software system that must be available 24 hours per day?

Use RAID 1, 5, 6, 10, 50, or 60.

*

Will the information stored in this drive group contain large audio or video files that must be available on demand?

Use RAID 0 or 00.

*

Will this drive group contain data from an imaging system?

Use RAID 0, 00, or 10.

Fill out the following table to help you plan the drive group configuration. Rank the requirements for your drive group, such as storage space and data redundancy, in order of importance, and then review the suggested RAID levels.

Table 17. Factors to Consider for Drive Group Configuration

Requirement

Rank

RAID Levels

 Storage space

RAID 0, RAID 5, RAID 00

 Data redundancy

RAID 5, RAID 6, RAID 10, RAID 50, RAID 60

 Drive performance and throughput

RAID 0, RAID 00, RAID 10

 Hot spares (extra drives required)

RAID 1, RAID 5, RAID 6, RAID 10, RAID 50, RAID 60