A network administrator recently updated various network devices to ensure redundancy throughout the network. If an interface on any of the Layer 3 devices were
to go down, traffic will still pass through another interface and the production environment would be unaffected. This type of configuration represents which of the
following concepts?

A.
High availability

B.
Load balancing

C.
Backout contingency plan

D.
Clustering

Explanation:
High availability (HA) refers to the measures used to keep services and systems operational during an outage. In short, the goal is to provide all services to all
users, where they need them and when they need them. With high availability, the goal is to have key services available 99.999 percent of the time (also known as
five nines availability).
Incorrect Answers:
B: Load balancing is one of the ways that high availability can be obtained because it allows you to split the workload across multiple computers
C: Backout contingency plan is a reversion from a change that had negative consequences.
D: Clustering is done whenever you connect multiple computers to work and act together as a single server. It is meant to utilize parallel processing and can also
add to redundancy.

Dulaney, Emmett and Chuck Eastton, CompTIA Security+ Study Guide, Sixth Edition, Sybex, Indianapolis, 2014, pp 32, 443