Single point of failure

When looking at a technical system, a single point of failure is a component that will stop the whole system from working if it fails. Systems that are built for high availability or reliability usually are designed to avoid single point of failures. This is usually done by adding redundancy, which is more than one thing that can do the same work.

Single Point Of Failure Media

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  Possible SPOFs in a simple setup

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  Using redundancy to avoid some SPOFs

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  Completely redundant system without SPOFs (note: assumes generator and grid sources are each rated at N, each UPS is rated at N, and "A/C" and "Electrical" are in and of themselves completely fault tolerant systems)