220-1101 Question 251
Single answerDrive configurationsA small office has a workstation used for basic file sharing and accounting. The owner wants the system to keep running if a single drive fails, but also wants as much usable storage as possible from two new 4 TB drives. The existing motherboard supports RAID configuration in firmware. Which drive configuration best meets these requirements?
- A
Configure the two drives as RAID 0
- B
Configure the two drives as RAID 1
- C
Configure the two drives as JBOD/spanned volume
- D
Configure the two drives as separate basic disks with one used for backups
Show answer and explanation
Correct answer: B
Explanation
The best answer is RAID 1 because the scenario requires fault tolerance with only two drives. In standard RAID configurations commonly tested on A+ Core 1, RAID 0 provides performance without redundancy, RAID 1 provides mirroring and survives a single-drive failure, and spanned/JBOD configurations increase capacity without fault tolerance. With two 4 TB drives, RAID 1 yields 4 TB usable capacity because one drive's capacity is used to mirror the other. This aligns with standard storage best practices: if availability after a single disk failure is required and only two drives are available, mirroring is the appropriate choice. CompTIA A+ objectives commonly expect candidates to distinguish RAID levels by purpose, capacity tradeoff, and fault-tolerance behavior.
- A. Incorrect.
RAID 0 stripes data across both drives for improved performance and full combined capacity, but it provides no fault tolerance. If either 4 TB drive fails, the entire array is lost. This is a common misconception because RAID 0 is often associated with using multiple drives efficiently, but it does not meet the requirement to continue operating after a single drive failure.
- B. Correct.
RAID 1 mirrors the same data to both drives. With two 4 TB drives in RAID 1, the system gets 4 TB of usable capacity and can continue operating if one drive fails. This directly meets the stated requirement for single-drive fault tolerance. Although it does not maximize total raw capacity, it provides the most usable storage possible while still maintaining redundancy with only two drives.
- C. Incorrect.
JBOD or a spanned volume combines capacity but does not provide true redundancy. Depending on the implementation, failure of one drive can cause loss of data stored on that drive or potentially affect the entire volume. It may appear attractive because it offers more space than RAID 1, but it does not satisfy the need for the system to remain operational after a single drive failure.
- D. Incorrect.
Using two separate basic disks with one as a backup target can support data protection if backups are performed correctly, but it does not provide drive fault tolerance for continuous operation. If the primary drive fails, the workstation will not keep running without restoration or replacement. This option reflects a common real-world practice for backup, but it is not the best answer for the specific requirement of immediate availability after a drive failure.