COMPTIA chapter 5.4 RAID

Jessica is concerned about losing data due to a hard disk failure. Her computer will only support a maximum of three disks. To protect her data, she has decided to use RAID (Redundant Array of Independent Disks). Which of the following RAID types would give Jessica the BEST mirrored data protection? Answer - RAID 0 - RAID 1 - RAID 5 - RAID 10

- RAID 1

You want to create a software RAID 1 array on your Windows 11 workstation using Disk 1 and Disk 2. What do you need to do with Disk 1 and Disk 2 before configuring them for a RAID 1 array? Answer -Convert the disks from basic to dynamic. -Format both disks with the same file system. -Convert the disks from dynamic to basic. -Verify that both disks are the same size.

-Convert the disks from basic to dynamic.

You have a computer with three hard disks. A RAID 0 volume uses space on Disk 1 and Disk 2. A RAID 1 volume uses space on Disk 2 and Disk 3. Disk 2 fails. Which of the following is true? Answer -Data on both volumes is inaccessible. -Data on both volumes is still accessible. -Data on the RAID 0 volume is accessible. Data on the RAID 1 volume is not. -Data on the RAID 1 volume is accessible. Data on the RAID 0 volume is not.

-Data on the RAID 1 volume is accessible. Data on the RAID 0 volume is not.

You are configuring a new system, and you want to use a RAID 0 array for the operating system using SATA disks and a special controller card that includes a RAID processor. Which RAID method should you use? Answer -Operating system -JBOD -Software -Hardware

-Hardware

You have configured Disk 3 and Disk 4 on your Windows 11 workstation as a RAID 1 array with the NTFS file system, and you have assigned F as the drive letter for the array. Each disk has an individual storage capacity of 1 TB. However, when you check the available storage size of F, you notice that it only lists 1 TB (instead of 2 TB) of available disk storage space. What should you do to resolve the issue? Answer -You need to change to a RAID 5 array. -Make sure both disks are set to dynamic instead of basic. -Nothing. The RAID array is working as designed. -Change the volume to a spanned volume.

-Nothing. The RAID array is working as designed.

One of your customers wants you to build a personal server that he can use in his home. One of his concerns is making sure that he has at least one data backup stored on the server in the event that a disk fails. You have decided to back up his data using RAID. Since this server is for personal use only, the customer wants to keep costs down. Therefore, he would like to keep the number of drives to a minimum. Which of the following RAID systems would BEST meet the customer's specifications? Answer -RAID 0 -RAID 1 -RAID 5 -RAID 10

-RAID 1

A computer that is being used by the HR department needs to ensure that all of the data on that computer is protected from a single hard disk failure. The data needs to be read as quickly as possible, and the HR department would like to maximize drive use as much as possible. This computer can use up to three hard drives. Which of the following RAID types would meet these requirements and provide the BEST data protection? Answer -RAID 0 -RAID 1 -RAID 5 -RAID 10

-RAID 5

Which of the following drive configurations uses striping with parity for fault tolerance? Answer -RAID 0 -RAID 5 -RAID 10 -RAID 1

-RAID 5

You have been asked to implement a RAID 5 solution for an engineer's desktop workstation. What is the minimum number of hard disks you can use to configure RAID 5? Answer -Two -Three -Four -Five -Six

-Three

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 11. 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. Which of the following would be your BEST solution? Answer -Use striped volumes. -Use mirrored volumes. -Use RAID 5 volumes. -Use spanned volumes.

-Use mirrored volumes.

Just a Bunch of Disks (JBOD)

A configuration that places multiple disks in a single logical storage unit.

RAID

A disk sub-system that combines multiple physical disks into a single logical storage unit.

RAID 1 (mirroring)

A mirrored volume stores data to two (or more) duplicate disks simultaneously. If one disk fails, data is present on another disk. The system switches immediately from the failed disk to a functioning disk. Mirroring: - Provides fault tolerance for a single disk failure. - Does not increase performance. - Has overhead. Overhead is 1 / n where n is the number of disks. If data is written twice, half of the disk space is used to store the second copy of the data. - RAID 1 is the most expensive fault tolerant system. - Offers redundancy

RAID 0 (striping)

A stripe set breaks data into units and stores the units across a series of disks by reading and writing to all disks simultaneously. Striping: - Provides an increase in performance. - Does not provide fault tolerance. A failure of one disk in the set means all data is lost. - Has no overhead because all disk space is available for storing data. - No redundancy

hardware RAID Array

BIOS of the drives, enables control into RAID. Using a special controller card that includes a RAID Processor - Most expensive method - Best performance method

to create RAID arrays in windows one must first do what

Convert the disks in disk management from basic to dynamic disks.

Disk space in RAID configurations

Must be identical and have the same size of space on each disk. if the disk are different sizes then the resulting volume will be limited to the smallest disk size.

Software RAID array

Uses a driver and the system CPU for the controlling RAID operations. This is the slowest form of RAID

RAID 5 (Striping with distributed parity)

combines disk striping across multiple disks with parity for data redundancy. Parity information is stored on each disk. If a single disk fails, its data can be recovered using the parity information stored on the remaining disks. Striping with distributed parity: - Provides fault tolerance for a single disk failure. - Provides an increase in performance for read operations. - *Requires a minimum of three disks.* - Has an overhead of one disk in the set for parity information (1 / n). - A set with 3 disks has 33% overhead. - A set with 4 disks has 25% overhead. - A set with 5 disks has 20% overhead.

RAID 10 (stripe of mirrors)

stripes data across mirrored pairs and across multiple disks for data redundancy. If a single disk fails, its data can be recovered using the mirrored information stored on the remaining disks. If two disks in the same mirrored pair fail, all data will be lost because there is no redundancy in the striped sets. - Provides a fault tolerance for a single disk failure - Provides redundancy and performance - Uses 50% of the total raw capacity of the drives due to mirroring. - *Requires a minimum of four disks.*

Operating System RAID Array

uses RAID features within the OS - the system CPU is used for RAID operations - Performance is typically better than software RAID bc of the integration with the OS.