Duplication of critical components or systems to provide backup if primary elements fail.
Redundancy is the duplication of critical components, systems, or processes to provide backup capacity if primary elements fail. Redundancy eliminates single points of failure—if one component fails, another takes over. Redundancy applies at multiple levels: hardware (redundant power supplies, RAID storage), network (multiple internet connections), systems (clustered servers), and sites (geographically distributed data centres). Redundancy costs money but provides resilience.
Why It Matters
The DSC Perspective:
Single points of failure are disasters waiting to happen. Identify critical components and ensure appropriate redundancy. The cost of redundancy is usually less than the cost of extended outages.