RAID Array Failures Troubleshooting

1. Which RAID configuration is best for high-availability database servers requiring both redundancy and performance?

RAID 0

RAID 1

RAID 5

RAID 10

2. After replacing a failed disk in a RAID 5 array, the system begins rebuild. How long should you expect the process to take for a 2TB disk?

5-10 minutes

30 minutes to 2 hours depending on workload and controller speed

Instant completion

24+ hours

3. In RAID monitoring, what does 'UER' (Unrecoverable Error Rate) indicate?

Disk read/write performance metrics

Errors that cannot be recovered by RAID parity

Network connection failures

Controller firmware issues

4. A server shows multiple disk errors across different disks simultaneously. What should you investigate first?

Replace all disks

RAID controller or cable issues rather than disk failures

Perform immediate array rebuild

Restore from backup

5. What is the purpose of RAID controller cache in troubleshooting scenarios?

Store redundancy information only

Improve performance and protect against data loss during power failures

Detect disk failures automatically

Reduce rebuild time

6. When a RAID array fails to rebuild after replacing a disk, what is a likely cause?

Insufficient power supply

Second disk failure during rebuild

Network timeout

Operating system update

7. RAID write penalty refers to the extra I/O operations required when writing to a RAID array. Which RAID level has the highest write penalty?

RAID 1

RAID 5

RAID 6

RAID 0

8. A RAID 5 array shows sector errors on one disk. What is the recommended troubleshooting step?

Run disk check utilities and monitor error growth

Immediately replace the disk

Disable error logging

Move data to a different array

9. What is rebuild time in a RAID context?

Time to replace a failed disk

Time to restore the entire array to full redundancy after disk replacement

Time to detect a disk failure

Time to backup array data

10. Hot spare disks in a RAID array serve what primary purpose?

Increase read performance

Automatically replace failed disks to maintain redundancy

Store backup copies of critical data

Reduce rebuild time

11. What does RAID stand for in server storage architecture?

Redundant Array of Independent Disks

Rapid Access Independent Data Storage

Redundant Allocation of Integrated Drives

Random Array of Interconnected Devices

12. A RAID controller reports a disk as offline but the disk is physically present. What should you attempt first?

Replace the disk immediately

Reseat the disk and check cable connections

Perform a full array rebuild

Restore from backup

13. What does S.M.A.R.T. stand for in disk monitoring?

System Monitoring and Redundancy Technology

Self-Monitoring, Analysis and Reporting Technology

Storage Management and Recovery Toolkit

Server Maintenance Automated Response Threshold

14. During RAID rebuild, what is the primary concern that can lead to complete data loss?

Network connectivity issues

A second disk failure during the rebuild process

Loss of electrical power

Controller firmware corruption

15. A RAID array shows predictive failure alerts on one disk. What should be your first action?

Ignore the alert and monitor performance

Immediately power down the server

Schedule disk replacement and perform a backup

Rebuild the RAID array immediately

16. Which monitoring tool is commonly used to check RAID status on Linux servers?

/proc/mdstat

/var/raid/status

/etc/fstab

/sys/disks/raid

17. When a disk fails in a RAID array, the system enters degraded mode. What is the primary risk during this state?

No performance impact

Loss of all data immediately

Vulnerability to second disk failure causing total data loss

Automatic replacement of the failed disk

18. What is the primary advantage of RAID 6 over RAID 5?

Faster write performance

Tolerance for two simultaneous disk failures

Lower cost per gigabyte

Simpler hardware requirements

19. In RAID 5, how many disk failures can the array tolerate before data loss occurs?

Zero failures

One failure

Two failures

Three failures

20. Which RAID level provides striping without redundancy, offering the highest performance but no fault tolerance?

RAID 0

RAID 1

RAID 5

RAID 6

Server+ Troubleshooting RAID Array Failures Quiz

1. Which RAID configuration is best for high-availability database servers requiring both redundancy and performance?

2.

What first name or nickname would you like us to use?

2. After replacing a failed disk in a RAID 5 array, the system begins rebuild. How long should you expect the process to take for a 2TB disk?

3. In RAID monitoring, what does 'UER' (Unrecoverable Error Rate) indicate?

4. A server shows multiple disk errors across different disks simultaneously. What should you investigate first?

5. What is the purpose of RAID controller cache in troubleshooting scenarios?

6. When a RAID array fails to rebuild after replacing a disk, what is a likely cause?

7. RAID write penalty refers to the extra I/O operations required when writing to a RAID array. Which RAID level has the highest write penalty?

8. A RAID 5 array shows sector errors on one disk. What is the recommended troubleshooting step?

9. What is rebuild time in a RAID context?

10. Hot spare disks in a RAID array serve what primary purpose?

11. What does RAID stand for in server storage architecture?

12. A RAID controller reports a disk as offline but the disk is physically present. What should you attempt first?

13. What does S.M.A.R.T. stand for in disk monitoring?

14. During RAID rebuild, what is the primary concern that can lead to complete data loss?

15. A RAID array shows predictive failure alerts on one disk. What should be your first action?

16. Which monitoring tool is commonly used to check RAID status on Linux servers?

17. When a disk fails in a RAID array, the system enters degraded mode. What is the primary risk during this state?

18. What is the primary advantage of RAID 6 over RAID 5?

19. In RAID 5, how many disk failures can the array tolerate before data loss occurs?

20. Which RAID level provides striping without redundancy, offering the highest performance but no fault tolerance?