滚动更新与回滚
使用 Kubernetes 滚动更新安全发布新版本，控制发布策略，并在出现问题时立即回滚
滚动更新与回滚 是 CoddyKit 上的免费 Docker & Kubernetes for Developers 课时。 这是第 4 节课，共 4 节。 你可以在下方免费阅读本课时的完整内容 — 然后在浏览器中使用内置代码编辑器和全天候 AI 导师进行实践。 这是 Docker & Kubernetes for Developers 学习路径的一部分，你的进度在网页和 CoddyKit 应用中同步。 Docker & Kubernetes for Developers 课程共包含 4 节课。
本课时的部分内容尚未翻译，以英文显示。
Why Rolling Updates
Updating every Pod at once causes downtime. A rolling update replaces Pods gradually so the app stays available throughout the change.
Deployments Drive Updates
A Deployment owns a ReplicaSet. Changing the Pod template makes the Deployment create a new ReplicaSet and shift Pods from old to new at a controlled pace.
Triggering an Update
Change the image and the Deployment starts a rollout automatically.
kubectl set image deployment/web web=myapp:2.0maxSurge and maxUnavailable
The strategy is tuned by two values: maxSurge (extra Pods allowed above desired) and maxUnavailable (Pods allowed to be down) during the rollout.
spec:
strategy:
type: RollingUpdate
rollingUpdate:
maxSurge: 1
maxUnavailable: 0Watching a Rollout
Track progress and confirm it finished cleanly.
kubectl rollout status deployment/webReadiness Gates the Rollout
A new Pod only receives traffic once its readiness probe passes. Without good probes, broken Pods can still get traffic during a rollout.
Pausing and Resuming
Pause a rollout to verify a canary subset, then resume.
kubectl rollout pause deployment/web
kubectl rollout resume deployment/webViewing Rollout History
Kubernetes keeps a revision history you can inspect.
kubectl rollout history deployment/webRolling Back
If the new version misbehaves, roll back to the previous revision instantly.
kubectl rollout undo deployment/webRolling Back to a Specific Revision
Target an exact revision from the history list.
kubectl rollout undo deployment/web --to-revision=3revisionHistoryLimit
Control how many old ReplicaSets are retained for rollback with revisionHistoryLimit in the Deployment spec.
spec:
revisionHistoryLimit: 5Quick Check
Test what you have learned.
Recap
You learned how Deployments perform rolling updates via ReplicaSets, how maxSurge/maxUnavailable and readiness probes control safety, and how to pause, watch, and rollout undo to recover fast.
常见问题解答
「滚动更新与回滚」课时是免费的吗？
是的 — 「滚动更新与回滚」的完整文本可在网页上免费阅读。要进行交互式练习（内置代码编辑器和全天候 AI 导师）并解锁 Docker & Kubernetes for Developers 课程的其余内容，请升级到 CoddyKit PRO。 Docker & Kubernetes for Developers 课程共包含 4 节课。
「滚动更新与回滚」这节课中我会学到什么？
使用 Kubernetes 滚动更新安全发布新版本，控制发布策略，并在出现问题时立即回滚 你通过在浏览器中直接运行的动手代码来练习 Docker & Kubernetes for Developers，全天候 AI 导师会在你学习这节课的过程中回答你的问题。
学习 Docker & Kubernetes for Developers 需要有经验吗？
无需任何先前经验。CoddyKit 上的 Docker & Kubernetes for Developers 课程适合初学者到高级学习者，你可以从这里开始或从头开始，按照自己的节奏学习。 这是第 4 节课，共 4 节。
「滚动更新与回滚」课时需要多长时间？
大多数 CoddyKit 课程大约需要 5–10 分钟。每节课都很精短且互动，所以你能稳步进步，并在网页和应用中从离开的地方继续。
我能在这节 Docker & Kubernetes for Developers 课中编写并运行代码吗？
能。每节 Docker & Kubernetes for Developers 课都包含内置代码编辑器，你可以在浏览器中直接编写并运行真实代码，并获得即时 AI 反馈 — 无需本地设置。