What is Redundancy?
Redundancy in hosting refers to the duplication of critical system components and data so that if one component fails, a backup can take over immediately. Redundancy is applied to hardware, network connections, power supplies, storage, and entire servers to minimize downtime.
How Does Redundancy Work?
Hosting providers achieve redundancy through multiple strategies including RAID storage arrays that mirror data across disks, redundant network paths that reroute traffic if a link fails, and dual power feeds connected to separate utility grids with battery and generator backup. At the server level, failover clusters allow a standby server to take over if the primary goes offline.
Redundancy is a core principle of high-availability architecture and is directly related to uptime guarantees in service level agreements. The more layers of redundancy a hosting environment has, the higher its fault tolerance and the less likely a single hardware failure will cause a service interruption. However, redundancy increases infrastructure costs, so the level of redundancy should match the criticality of the hosted applications.