Implementing Disk Redundancy for Database Servers: RAID Configurations for Minimum Disk Usage

RAID Configurations for Minimal Disk Usage

Prev Question Next Question

Question

A server administrator is implementing disk redundancy in all database servers.

Which of the following RAID configurations should the administrator use so that a MINIMUM number of disks are required?

Answers

Explanations

Click on the arrows to vote for the correct answer

A. B. C. D.

B.

The goal of implementing disk redundancy is to ensure that data is protected in the event of a disk failure. There are several RAID (Redundant Array of Independent Disks) configurations available, each with its own benefits and drawbacks. The administrator needs to select a RAID configuration that offers the best balance between disk redundancy and disk utilization, while minimizing the number of disks required.

RAID 0 (striping) offers the highest performance but does not provide any redundancy. Data is split across multiple disks, which can improve read and write speeds. However, if one disk fails, all data is lost. RAID 0 is not a suitable option for database servers where data integrity is critical.

RAID 1 (mirroring) duplicates data on two or more disks, providing redundancy. However, this means that disk utilization is lower than other RAID configurations since only half of the total disk space is usable. RAID 1 is a good choice for small databases or systems where data redundancy is critical.

RAID 5 requires at least three disks and provides a good balance between performance and redundancy. Data is distributed across all disks, and parity information is stored on each disk. If a disk fails, the parity information can be used to rebuild the lost data. However, performance can be impacted during the rebuilding process. RAID 5 is a common choice for medium-sized databases.

RAID 6 is similar to RAID 5 but requires at least four disks. It offers double parity protection, which means that it can withstand two disk failures without losing data. However, the overhead for maintaining the parity information means that performance can be slower than RAID 5. RAID 6 is a good choice for large databases where data loss would be catastrophic.

Based on the above, the best RAID configuration for a database server that requires disk redundancy while minimizing the number of disks required would be RAID 5. RAID 5 provides a good balance between performance and redundancy, while requiring only a minimum of three disks.