I assume you know what redundancy is. Can you tell me can you use it on a server? What components is it referring to?

In computing, failover is switching to a redundant or standby computer server, system, hardware component or network upon the failure or abnormal termination of the previously active application, server, system, hardware component, or network.

 

Server redundancy refers to the amount and intensity of backup, failover or redundant servers in a computing environment. It defines the ability of a computing infrastructure to provide additional servers that may be deployed on runtime for backup, load balancing or temporarily halting a primary server for maintenance purposes.