Question

Darcy is designing a fault tolerant system and wants to implement RAID-5 for her system. What is the minimum number of physical hard disks she can use to build this system?

1) One
2) Two
3) Three
4) Five

Answer 1

To implement RAID-5, the minimum number of physical hard disks required is three. This level of RAID provides fault tolerance by combining striping with parity, allowing the system to recover data if one disk fails.

Step-by-step explanation:

The student asked about the minimum number of physical hard disks required to build a RAID-5 system. RAID-5 is a storage technology that combines disk striping with parity. This means that the data is spread across multiple disks with an additional parity bit written to one of the disks. The parity bit allows the system to recover data in case one of the disks fails, making it fault tolerant.

To implement RAID-5, a minimum of three physical hard disks are needed. With two disks, you would only be able to implement RAID-0 (striping without parity) or RAID-1 (mirroring without striping or parity), neither of which offers the same level of fault tolerance as RAID-5.

Therefore, the correct answer is 3) Three.