|
Two or more servers are configured in a cluster arrangement to operate as a "virtual" SQL server. Each server has software locally installed AND also installed via a shared sub-system with the other servers in the cluster.
A "heartbeat" is heard between servers in the cluster, ensuring each server is functioning properly, if not, then "Failover" occurs - i.e if one machine in the cluster fails, another assumes the responsibilities of the downed server thus the
hardware failure does not result in loss of functionality for the application. (Voyager) |
|