Failover involves the automatic switching of functions from a primary device, such
as a server or router, to a secondary device, in the event the primary device is
no longer operational. The secondary device receiving the failover could have extra
capacity or be a spare unit kept on-line in reserve. The goal of the failover process
is to be as seamless as possible so as to not be noticeable to end users.
Failover Benefits and Issues
Failover is an integral part of mission critical systems where redundancy is required.
Failover typically involves the use of clusters or a backup system in a geographically
separate location. While failover provides an increased level of fault tolerance
it is not a simple task to accomplish. Clustering and failover require a great deal
of technical knowledge if the system is to be properly set-up and maintained. Make
sure your internal resources or external hosting provider have failover expertise
before you assign them the failover task.