CompTIA Security Plus Mock Test Q410

Which of the following provides the LEAST availability?

A. RAID 0
B. RAID 1
C. RAID 3
D. RAID 5

Correct Answer: A
Section: Compliance and Operational Security

Explanation:
RAID, or redundant array of independent disks (RAID). RAID allows your existing servers to have more than one hard drive so that if the main hard drive fails, the system keeps functioning. RAID 0 is disk striping. It uses multiple drives and maps them together as a single physical drive. This is done primarily for performance, not for fault tolerance. If any drive in a RAID 0 array fails, the entire logical drive becomes unusable.
Incorrect Answers:
B: RAID 1 is disk mirroring. Disk mirroring provides 100 percent redundancy because everything is stored on two disks. If one disk fails, another disk continues to operate. The failed disk can be replaced, and the RAID 1 array can be regenerated. This system offers the advantage of 100 percent data redundancy at the expense of doubling the storage requirements. Each drive keeps an exact copy of all information, which reduces the effective storage capability to 50 percent of the overall rated storage.
C: RAID 3 is disk striping with a parity disk. RAID 3 arrays implement fault tolerance by using striping (RAID 0) in conjunction with a separate disk that stores parity information. Parity information is a value based on the value of the data stored in each disk location. This system ensures that the data can be recovered in the event of a failure. The process of generating parity information uses the arithmetic value of the data binary. This process allows any single disk in the array to fail while the system continues to operate.
D: RAID 5 is disk striping with parity, and it is one of the most common forms of RAID in use today. It operates similarly to disk striping, as in RAID 0. The parity information is spread across all of the disks in the array instead of being limited to a single disk, as in RAID 3. Most implementations require a minimum of three disks and support a maximum of 32.

References:
Dulaney, Emmett and Chuck Eastton, CompTIA Security+ Study Guide, 6th Edition, Sybex, Indianapolis, 2014, pp. 34-35, 234

CompTIA Security Plus Mock Test Q409

Which of the following provides data the best fault tolerance at the LOWEST cost?

A. Load balancing
B. Clustering
C. Server virtualization
D. RAID 6

Correct Answer: D
Section: Compliance and Operational Security

Explanation
RAID, or redundant array of independent disks (RAID). RAID allows your existing servers to have more than one hard drive so that if the main hard drive fails, the system keeps functioning. RAID can achieve fault tolerance using software which can be done using the existing hardware and software thus representing the lowest cost option.
Incorrect Answers:
A: Load balancing is a way of providing high availability by splitting the workload across multiple computers. This in itself means more costs if you do not already have the multiple computers.
B: Anytime you connect multiple computers to work/act together as a single server, it is known as clustering. Clustered systems utilize parallel processing (improving performance and availability) and add redundancy (but also add costs).
C: Virtualization is the foundation for cloud computing. You cannot have cloud computing without virtualization. It makes it possible by abstracting the hardware and making it available to the virtual machines. The abstraction is done through the use of a hypervisor, which can be either Type I (bare metal) or Type II (hosted). It is not a method used for fault tolerance.
References:
Dulaney, Emmett and Chuck Eastton, CompTIA Security+ Study Guide, 6th Edition, Sybex, Indianapolis, 2014, pp. 234-235

CompTIA Security Plus Mock Test Q408

Which of the following may significantly reduce data loss if multiple drives fail at the same time?

A. Virtualization
B. RAID
C. Load balancing
D. Server clustering

Correct Answer: B
Section: Compliance and Operational Security

Explanation:
RAID, or redundant array of independent disks (RAID). RAID allows your existing servers to have more than one hard drive so that if the main hard drive fails, the system keeps functioning.
Incorrect Answers:
A: Virtualization is the foundation for cloud computing. It makes it possible by abstracting the hardware and making it available to the virtual machines. The abstraction is done through the use of a hypervisor, which can be either Type I (bare metal) or Type II (hosted); not at all reducing data loss in case multiple drives fail.
C: Load balancing is a way of providing high availability by splitting the workload across multiple computers; however it does not reduce data loss in case multiple drives happen to fail.
D: Anytime you connect multiple computers to work/act together as a single server, it is known as clustering. Clustered systems utilize parallel processing (improving performance and availability) and add redundancy (but also add costs).

References:
Dulaney, Emmett and Chuck Eastton, CompTIA Security+ Study Guide, 6th Edition, Sybex, Indianapolis, 2014, pp. 234-235