High Availability Systems
High Availability (HA) Systems are architectural designs and implementations that ensure a service or application remains operational and accessible with minimal downtime, typically targeting 99.9% uptime or higher. They achieve this through redundancy, failover mechanisms, and fault tolerance to handle hardware failures, software errors, or maintenance events. This concept is critical in industries like finance, healthcare, and e-commerce where continuous service is essential.
Developers should learn and implement High Availability Systems when building mission-critical applications that require reliability and minimal disruption, such as online banking platforms, e-commerce sites, or cloud services. It is particularly important in distributed systems, microservices architectures, and cloud-native environments to prevent single points of failure and ensure business continuity during outages or scaling events.