5.4.7 Practice Questions RAID

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

3 Explanation A RAID 5 array stripes data and parity information across multiple hard disks. To complete a RAID 5 array, a minimum of three hard disks is required. A RAID 0 and RAID 1 can both be implemented with a minimum of two hard disks.

You have been asked to implement a RAID 10 solution for a video editor's desktop workstation. What is the minimum number of hard disks that can be used to configure RAID 10?

4 Explanation A RAID 10 array nests a mirrored array within a striped array. To create a RAID 10 array, a minimum of four hard disks is required (two for the mirrored array and two more to stripe the mirror).

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?

Data on the RAID 1 volume is accessible; data on the RAID 0 volume is not. Explanation In this scenario, Disk 2 is shared between both volumes. If Disk 2 fails, the RAID 1 is still accessible because RAID 1 (mirrored) volumes can sustain a loss of a single disk. The data on the RAID 0 volume is not accessible. RAID 0 uses striping, which distributes the data evenly between multiple disks. If a single disk fails, the entire volume is lost.

Procedure

Important: When accessing the Drive Bays and Motherboard make sure that the computer is turned off. 1. Click on Drive Bays. 2. Install three Hard Drives, Internal, SATA. 3. Click on Power Supply. 4. Select the 15-pin SATA connector and provide power to the three Hard Drives. 5. Click the Cable. 6. Select the SATA Cable Three Times. Remember that there are Partial Connections. 7. Click on Motherboard. 8. Connect the other end of the SATA cables to the SATA connectors on the Motherboard. 9. Click Front. 10. Turn on the computer and press Delete to enter the BIOS. 11. Click on System Configuration. 12. Click on SATA Operation. 13. Select RAID On. 14. Click Apply. 15. Click Exit. 16. Press Ctrl+I to the RAID Configuration. 17. Press 1 to Create RAID volume. 18. Leave the name as Volume 0. 19. Press Tab to go to the RAID Level. 20. Use the Arrow Buttons to Select RAID 5, which provides both fault tolerance and improved performance. 21. Leave Disks, Stripe Size, and Capacity. 22. Press Enter to create the Specified volume. 23. When the warning: ALL DATA ON SELECTED DISKS WILL BE LOST are you sure you want to create this volume> (Y/N) press Y for Yes. 24. Check the Disk Volume Information. 25. Press Done.

Your computer currently runs Windows 7 Enterprise edition. You want to create a RAID 5 array using three newly-installed SATA disks. When you go to Disk Management, the option to create the RAID 5 array is not available. What should you do?

Install an add-on RAID controller Explanation Windows 7 desktop operating systems support creating RAID 0 and RAID 1 arrays in Disk Management, bu do not support configuring RAID 5. To use RAID 5 on a client computer, you will need to use a RAID controller installed in an expansion slot or integrated in the motherboard.

You have an existing computer running Windows 7 Enterprise. You want to configure a RAID 1 array in the computer. You install two new SATA drives, then use the RAID controller integrated in the motherboard to define a RAID 1 array using them. When you boot the computer, Windows does not show the logical RAID drive. What should you do?

Install the drivers for the RAID controller. Explanation You must install the RAID driver so that Windows recognizes arrays created by the motherboard RAID utility. Without the driver, Windows will not be able to see the logical drive defined by the array. When you define the array, you configure the BIOS to use RAID as the SATA type. If you had not completed this step, you would not be able to run the RAID configuration utility,. Use AHCI to configure SATA drives to support hot-swapping.

You are configuring a new system and want to use a RAID 0 array for the operating system using SATA disks and the RAID functionality built into the motherboard. Which of the following actions will you take as part of the configuration?

Load the RAID drivers during operating system installation. Explanation If using an onboard RAID controller with SATA drives, edit the CMOS settings and identify the drive type as RAID. This tells the system to load the onboard BIOS for accessing the connected drive. If you want to install the operating system on a RAID array, you will need to manually load the controller driver so that Windows can see the RAID array.

Which RAID configuration level provides increased using only two disks?

RAID 0 Explanation RAID 0 (striping) uses two or more disks and provides an increase in performance but not fault tolerance. RAID 1 (mirroring) uses two disks to provide fault tolerance but not an increase in performance. RAID 5 uses a minimum of three disks and provides both fault tolerance and an increase in read performance.

Which of the following drive configurations uses striping without fault tolerance?

RAID 0 Explanation RAID 0 uses disk striping and offers no fault tolerance. Disk striping breaks data into units and stores the units across a series of disks by reading and writing to all disks simultaneously. A failure of one disk in the set means all data is lost. This is the fastest of all RAID types. RAID 5 also uses disk striping, but provides fault tolerance for a single disk failure. RAID 1 provides fault tolerance but does not use striping. An expanded volume set is a volume that spans more than one hard drive. An expanded volume set also offers no fault tolerance, yet does not use striping.

Which of the following drive configuration uses striping with parity for fault tolerance?

RAID 5 Explanation RAID 5 also uses disk striping, but provides fault tolerance for a single disk failure. Disk striping breaks data into units and stores the units across a series of disks by reading and writing to all disks simultaneously. RAID 0 uses disk striping and offers no fault tolerance. A failure of one disk in the set means all data is lost. RAID 1 provides fault tolerance but does not use striping. A RAID 10 array nests a mirrored array within a striped array.

What is an advantage of RAID 5 over RAID 1?

RAID 5 improves performance over RAID 1. Explanation RAID provides both fault tolerance and improved performance RAID (mirroring) provides only fault tolerance with no performance benefit. Both RAID 5 and RAID 1 can only sustain a loss of one disk in the set. Use multiple disk controllers to provide redundancy for the disk controller.

Lab Report

Task Summary Install three hard drives. Set the SATA Operation mode in the BIOS to RAID. Create a RAID 5 array with three disks. Configure three drives in the array. Configure the RAID array as RAID 5. Use a total capacity on the disks. Explanation To complete this lab: Create a RAID 5 array to provide both fault tolerance and increased performance. A RAID 0 array increases performance only, while a RAID 1 array provides only fault tolerance. Install three disks to create RAID 5 array. A RAID 5 array requires a minimum of three disks. Complete the following steps: 1. On the computer, switch to the drive bays view. 2. On the Shelf, expand the Hard Drives category. 3. Drag a hard drive to a free 3.5" drive bay. 4. Repeat step 3 to add additional hard drives are required by the scenario. 5. To connect the hard drives to the motherboard, on the Shelf, expand the Cables category. 6. Select a cable. In the Selected Component window, drag a connector end to the hard drive. 7. Repeat step 6 to connect cable to additional hard drives. 8. On the computer, switch to the motherboard view. 9. In the Partial Connections list for the computer, select a SATA cable. 10. In the Selected Component window, drag the unconnected cable end to the motherboard SATA connector. 11. Repeat steps 9 and 10 to connect additional SATA cables to the motherboard. 12. To connect the power cables, select the power supply. 13. On the computer, switch to the Drive Bays view. 14. In the Selected Component window, drag a SATA power connector to a hard drive. 15. Repeat step 14 to connect power to the other drive (s). 16. Switch to the front view of the computer. 17. Turn on the computer. 18 As the computer, press the Delete key to enter the BIOS setup program. 19. To configure the SATA drive mode, open System Configuration in the drop-down menu on the left. 20. Select SATA Operation. 21. Select RAID On and click Apply. 22. Select Exit to restart the system. 23. As the system boots, after the BIOS loads the RAID controller will load. Press Ctrl + I when you see the message on the screen. 24. Select Create RAID Volume and press Enter. 25. Press Enter. 26. Use the up and down arrow keys to define the RAID Level. 27. Press Enter. 28. Use the up and down arrow keys to define the stripe size. 29. Press Enter. 30. Press Enter to accept the default capacity and continue. 31. Press Enter. 32. When prompted, press Y. 33. Press Esc, then Y to restart.

Scenario

You work part-time at a computer repair store. You are in the process of constructing a new system. You would like to install the operating system on a RAID array that provides both fault tolerance and improved performance (RAID 5: Striping with distributed parity). Your task in this lab is to: - Add the minimum number of disks to the computer to create the RAID array that meets the scenario requirements. Do not remove extra disks from the Shelf. - Connect all disks to the motherboard and provide power for the disks. - Boot the computer and configure a RAID array using the motherboard RAID configuration utility. - Choose the RAID level based on the scenario requirements. - Configure the array to use all of the disk space on the installed disks.