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).