How do you implement fault isolation in microservices?

Fault isolation is a technique that limits the propagation of failures in individual microservices, ensuring that local issues do not affect the entire system. Its importance lies in improving availability and resilience, with application scenarios including high-demand environments such as e-commerce or financial systems.

The core components include service boundaries, circuit breaker patterns, timeout and retry mechanisms, and API gateways. The principle is based on isolating fault domains, such as pausing failed calls through circuit breakers. In practical applications, it prevents cascading failures and optimizes the robustness and maintainability of microservice architectures.

Implementation steps: first define service boundaries, then deploy circuit breakers (e.g., Hystrix), configure timeout and rate-limiting policies, and integrate service meshes (e.g., Istio) for automated management. The business value is to enhance system reliability, reduce operational costs, and improve user experience.