Application Servers actively working in the iControl system are known as Main Application Servers. Application Servers on which copies of configuration data from the Main Application Servers reside are known as Backup Application Servers. If one of the Main Application Servers fails, an operator can manually switch service to a Backup Application Server, or else the system can automatically fail over to a Backup Application Server if configured to do so.

A necessary condition for a successful Auto-failover or Manual Takeover is for the Main Application Server’s iControl software and Web sites, configuration data, and IP address configuration data to be replicated and up-to-date on the Backup Application Server. Replication is the automatic scheduled copying of Application Servers on the network. Configuration of the replication function is done through iControl Admin (click HERE). After a failover, the Backup Application Server assumes the exact same configuration profile as the original Main at the time of its last replication (that is, operational status, IP addresses, configuration data are identical to the replication snapshot).