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