What is a Single Point of Failure?

A single point of failure (SPoF) is a part of a system or product that will lead to downtime if it fails. Within a server room or data centre environment, critical infrastructure systems are designed and installed to remove single points of failure, using N+X configurations that provide redundancy in the system design. An N+1 system configuration, removes a single point of failure by providing a second system that can take over from the first, should there be a failure. Typical arrangements include modular UPS and cooling systems but if one of the ‘+X’ elements goes off-line, so that the system is reliant on its N (single) system, then the system has a single point of failure. Regular data centre inspection and system maintenance can identify and help to prevent single points of failures.