How to Build IT Infrastructure That Is Truly Highly Available

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The term 'high availability' has become so overused in the tech industry that it has lost its precise meaning, often applied to systems that have never been rigorously designed to a specific uptime target. True high availability requires setting a concrete availability percentage per system — such as 99.95%, which allows roughly 4.4 hours of downtime annually — based on measurable business impact. A common failure in practice is assembling redundant-looking components without tracing end-to-end dependencies, leaving hidden single points of failure, such as two database servers sharing one storage array. Redundancy itself operates at distinct levels — component, system, and site — and each addresses a different class of failure, making them non-interchangeable in design. Achieving genuine high availability demands verified, calculated design rather than assumed redundancy from architecture diagrams.

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ProgrammingDEV Community ·

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ProgrammingDEV Community ·

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ProgrammingDEV Community ·

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