RAID

RAID

Mr. Burnside

RAID Concepts

RAID: Redundant Array of Independent Disks 

RAID provides a way to store data across multiple storage devices for availability, reliability, capacity, and redundancy and/or performance improvement

Multiple Choice

What is Redundant Array of Independent Disks (RAID)?

• a technology to store data across multiple storage devices for availability, reliability, capacity, redundancy, or performance improvement

• a chip that performs the rapid mathematical calculations required to render graphics

• a technique used when the processor runs at less than the rated speed in order to conserve power or produce less heat

How RAID stores data on the various disks:

Striping – enables data to be distributed across multiple drives with a significant performance increase, however the failure of a single drive means that all data is lost.

Mirroring – stores duplicate data on one or more other drives and provides redundancy so that the failure of a drive does not cause the loss of data. 

How RAID stores data on the various disks:

Parity – provides basic error checking and fault tolerance by storing checksums separately from data and enables the reconstruction of lost data without sacrificing speed and capacity.

Double Parity – provides fault tolerance for up to two failed drives

RAID levels

There are several levels of RAID available

These levels use mirroring, striping, and parity in different ways

Multiple Choice

A network administrator is setting up a web server for a small advertising office and is concerned with data availability. The administrator wishes to implement disk fault tolerance using the minimum number of disks required. Which RAID level should the administrator choose?

• RAID 0

• RAID 1

• RAID 6

• RAID 5

WHY RAID 1

Both RAID 0 and RAID 1 require at least 2 disks. However, RAID 0 does not provide fault tolerance. The minimum numbers of disks for RAID 5 and RAID 6 are 3 and 4 respectively.

Multiple Choice

You work for a small company as the human resources specialist. Since the company is fairly small, you are maintaining all of the employee information on your desktop computer, which is running Windows 10. This computer has two high-capacity hard disks. You want to ensure that this information is protected from a hard disk failure, so you want to set up a Windows software RAID system.

• Use RAID 5 volumes.

• Use spanned volumes.

• Use striped volumes.

• Use mirrored volumes.

Why mirrored

 Windows software RAID system can be configured in Windows 10 using the Windows Disk Management tool. Of the available options from within Disk Management, you would need to configure a mirrored volume to protect your data from a disk failur

Multiple Choice

Ben is concerned about losing data due to a hard disk failure. His computer will only support a maximum of three disks. To protect his data, you have decided to use RAID (redundant array of independent disks).

Which of the following RAID types would give Ben the BEST mirrored data protection

• RAID 0

• RAID 1

• RAID 5

• RAID 10

WHY RAID 1?

RAID 1 is the only mirrored solution that can work on three or less drives. RAID 0 and RAID 5 protects data using stripping. RAID 10 uses mirroring, but requires a minimum of four disks.

Multiple Choice

What is an advantage of RAID 5 over RAID 1?

• RAID 5 provides redundancy for the disk controller.

• RAID 5 improves performance over RAID 1

• RAID 5 provides redundancy; RAID 1 does not

Explanation

AID 5 provides both fault tolerance and improved performance. RAID 1 (mirroring) provides only fault tolerance with no performance benefit.

Multiple Choice

You have been asked to implement a RAID 5 solution for an engineer's desktop workstation. What is the minimum number of hard disks that can be used to configure RAID 5?

• 2

• 3

• 4

• 5