Describe the basic operation of a failover cluster.

What will be an ideal response?

A failover cluster consists of two or more servers, usually of identical configuration, that access common storage media. Typically, storage is in the form of a storage area network. The servers are connected to the SAN device through a secondary high speed network connection, such as iSCSI. One server in a failover cluster is considered the active server, and the other servers are considered passive. The active server handles all client requests for the clustered application, and passive servers wait in a type of standby mode. If the active server fails and stops responding, one of the passive servers becomes active and begins handling client requests.