Failover
From Wikipedia, the free encyclopedia
Failover is the capability to switch over automatically to a redundant or standby computer server, system, or network upon the failure or abnormal termination of the previously active server, system, or network. Failover happens without human intervention and generally without warning, unlike switchover.
Systems designers usually provide failover capability in servers, systems or networks requiring continuous availability and a high degree of reliability.
In some cases, computer system failover is not desired to be automatic, but is required to allow human intervention to effect the failover. This is called "automated with manual approval", as the activity is automatic once approval is given.
Failback, conversely, is the process of restoring a system/component/service in a state of failover back to its original state (before failure).