Scaling High-Availability Infrastructure in the Cloud High-availability infrastructure is crucial for ensuring that critical systems are always available, with a goal of achieving 99.999% uptime or "five nines" availability. This requires automated recovery from failures without human intervention, as manual processes can be impractical and time-consuming. One of the most challenging components to automate is the database, due to its complexity and need for significant human intervention in configuration and fail-over. The root causes of downtime often include data persistence issues and change control mistakes, making it hard to scale and manage stateful components. To build high-availability cloud applications, it's essential to differentiate between stateful and stateless components, avoid storing data where possible, and use unstructured storage instead of structured storage. Clearly defining human-mediated processes for change control and pragmatically selecting the right data storage technology are also crucial.