CompTIA Server+ (SK0-005)Server Hardware Installation and ManagementMedium
A server has eight 4TB SAS drives. The administrator wants to configure a RAID array that provides maximum usable storage capacity while still offering fault tolerance against a single drive failure. Which RAID level should the administrator choose?
- ARAID 0
- BRAID 1
- CRAID 5
- DRAID 6
Show answer & explanationAnswer & explanation
Correct answer: C. RAID 5
RAID 5 provides striping with distributed parity, allowing for maximum usable capacity (N-1 drives) while offering fault tolerance against a single drive failure. For 8 drives, this would yield 7 * 4TB = 28TB usable storage.
Why the other options are wrong
- A. RAID 0 provides maximum capacity (N drives) but no fault tolerance, which contradicts the requirement for single drive fault tolerance.
- B. RAID 1 (mirroring) would only provide 4TB of usable storage (N/2 drives mirrored) with 8 drives, which is not maximum usable capacity.
- D. RAID 6 uses two drives' capacity for parity, resulting in (N-2) usable drives, which is less capacity than RAID 5 (6 * 4TB = 24TB) and provides tolerance for two drive failures, exceeding the 'single drive failure' requirement for maximum capacity.
RAID 5 (Striping with Parity)
A RAID level that stripes data across multiple disks and distributes parity information among all disks. It provides fault tolerance against a single drive failure and offers a good balance of performance, capacity, and redundancy.
- Requires a minimum of 3 drives.
- Usable capacity is (N-1) * drive_size.
- Tolerates a single drive failure.
- Good for general-purpose server storage where capacity and single-drive redundancy are key.
Memory trick: RAID 5: Five's the Sweet Spot for Space and Safety.