概述
提升服务可靠性：设计优雅停机，调优健康探针，并验证系统在部分失效时能优雅降级而非级联崩溃。本工作流属于可靠性工程领域，目标是make the service survive restarts and partial dependency failures without dropping in-flight requests.以下步骤将指导你完成关键操作，并在每一步设置可验证的中间状态，确保最终结果可复现、可审计、可回滚。
步骤详解
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Implement graceful shutdown。 On SIGTERM, stop accepting new requests, drain in-flight work, and exit only after the drain completes or the grace period ends.预期状态：A rolling restart drops zero in-flight requests.
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Tune health probes。 Set the readiness probe to fail fast on dependency loss and the liveness probe to avoid killing the pod during a slow but healthy startup.预期状态：Probes correctly reflect readiness and do not cause false restarts.
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Verify graceful degradation。 Inject a dependency failure and confirm the service returns a controlled fallback instead of a 5xx cascade.预期状态：The service serves a fallback response and recovers when the dependency returns.
每一步都包含明确的动作与预期状态。执行时请记录实际输出，与预期状态逐一对照。若某一步未达预期，应停下排查而非继续推进，避免问题向后传递放大。
验证与后续
验证方法：make the service survive restarts and partial dependency failures without dropping in-flight requests.完成后，将本次执行的命令、输出与参数归档，并更新团队运行手册。若用于生产环境，请先在预发环境完整演练一次，并确认团队熟悉回滚路径与应急联系人。本工作流难度级别为进阶（intermediate），预计耗时约30分钟。该流程已通过结构化校验，步骤与决策点均与英文版本严格一致，可在本地按工作流步骤复现并核对结果。
代码示例
kubectl rollout restart deployment/api -n prod