How do microservices improve fault tolerance in large-scale applications?

Microservices are an architectural pattern that splits large applications into small, independent services, each running in a container and communicating via APIs. Their importance lies in enhancing fault tolerance, preventing system crashes caused by single failures, making them suitable for scenarios such as high-traffic e-commerce or financial platforms.

Core characteristics include service autonomy, lightweight communication such as gRPC and REST, and isolated deployment units. By isolating fault points, such as using service boundaries and distributed transaction management, microservices reduce the risk of error propagation. In practical applications, Kubernetes coordinates service instances, supports dynamic scaling and elastic strategies, significantly improving system availability and agility.

To improve fault tolerance, implementation steps include: deploying the circuit breaker pattern to isolate failed services; configuring retry and degradation mechanisms to handle temporary errors; integrating service meshes such as Istio for traffic monitoring and fault recovery; and combining log aggregation tools such as Prometheus for rapid diagnosis. This brings business value such as reduced downtime, enhanced user experience, and system reliability.