High availability

Availability is the percentage of time that a system is functioning and able to perform its mission. High availability is a characteristic of a system that aims to achieve an agreed level of availability, for a higher than normal period.

As one of the methods to improve system availability, redundancy reduces single points of failure. Duplicate hardware or software components within a system enable you to repair, replace, maintain, or recover from a failure with little to no disruption to operation.

For more information, see High Availability Systems.