delete original English text
This commit is contained in:
@@ -14,53 +14,12 @@ cn-reviewers:
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{% comment %}Updated: 4/14/2015{% endcomment %}
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{% comment %}Edited and moved to Concepts section: 2/2/17{% endcomment %}
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<!--
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This page describes the lifecycle of a Pod.
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-->
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该页面将描述 Pod 的生命周期。
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{% endcapture %}
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{% capture body %}
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<!--
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## Pod phase
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A Pod's `status` field is a
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[PodStatus](/docs/resources-reference/v1.6/#podstatus-v1-core)
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object, which has a `phase` field.
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The phase of a Pod is a simple, high-level summary of where the Pod is in its
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lifecycle. The phase is not intended to be a comprehensive rollup of observations
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of Container or Pod state, nor is it intended to be a comprehensive state machine.
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The number and meanings of Pod phase values are tightly guarded.
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Other than what is documented here, nothing should be assumed about Pods that
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have a given `phase` value.
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Here are the possible values for `phase`:
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* Pending: The Pod has been accepted by the Kubernetes system, but one or more of
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the Container images has not been created. This includes time before being
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scheduled as well as time spent downloading images over the network,
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which could take a while.
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* Running: The Pod has been bound to a node, and all of the Containers have been
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created. At least one Container is still running, or is in the process of
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starting or restarting.
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* Succeeded: All Containers in the Pod have terminated in success, and will not
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be restarted.
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* Failed: All Containers in the Pod have terminated, and at least one Container
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has terminated in failure. That is, the Container either exited with non-zero
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status or was terminated by the system.
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* Unknown: For some reason the state of the Pod could not be obtained, typically
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due to an error in communicating with the host of the Pod.
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-->
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## Pod phase
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Pod 的 `status` 定义在 [PodStatus](/docs/resources-reference/v1.7/#podstatus-v1-core) 对象中,其中有一个 `phase` 字段。
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@@ -77,68 +36,10 @@ Pod 相位的数量和含义是严格指定的。除了本文档中列举的内
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- 失败(Failed):Pod 中的所有容器都已终止了,并且至少有一个容器是因为失败终止。也就是说,容器以非0状态退出或者被系统终止。
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- 未知(Unknown):因为某些原因无法取得 Pod 的状态,通常是因为与 Pod 所在主机通信失败。
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<!--
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## Pod conditions
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A Pod has a PodStatus, which has an array of
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[PodConditions](/docs/resources-reference/v1.6/#podcondition-v1-core). Each element
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of the PodCondition array has a `type` field and a `status` field. The `type`
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field is a string, with possible values PodScheduled, Ready, Initialized, and
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Unschedulable. The `status` field is a string, with possible values True, False,
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and Unknown.
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-->
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## Pod 状态
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Pod 有一个 PodStatus 对象,其中包含一个 [PodCondition](/docs/resources-reference/v1.7/#podcondition-v1-core) 数组。 PodCondition 数组的每个元素都有一个 `type` 字段和一个 `status` 字段。`type` 字段是字符串,可能的值有 PodScheduled、Ready、Initialized 和 Unschedulable。`status` 字段是一个字符串,可能的值有 True、False 和 Unknown。
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<!--
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## Container probes
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A [Probe](/docs/resources-reference/v1.6/#probe-v1-core) is a diagnostic
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performed periodically by the [kubelet](/docs/admin/kubelet/)
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on a Container. To perform a diagnostic,
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the kubelet calls a
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[Handler](https://godoc.org/k8s.io/kubernetes/pkg/api/v1#Handler) implemented by
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the Container. There are three types of handlers:
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* [ExecAction](/docs/resources-reference/v1.6/#execaction-v1-core):
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Executes a specified command inside the Container. The diagnostic
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is considered successful if the command exits with a status code of 0.
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* [TCPSocketAction](/docs/resources-reference/v1.6/#tcpsocketaction-v1-core):
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Performs a TCP check against the Container's IP address on
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a specified port. The diagnostic is considered successful if the port is open.
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* [HTTPGetAction](/docs/resources-reference/v1.6/#httpgetaction-v1-core):
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Performs an HTTP Get request against the Container's IP
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address on a specified port and path. The diagnostic is considered successful
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if the response has a status code greater than or equal to 200 and less than 400.
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Each probe has one of three results:
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* Success: The Container passed the diagnostic.
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* Failure: The Container failed the diagnostic.
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* Unknown: The diagnostic failed, so no action should be taken.
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The kubelet can optionally perform and react to two kinds of probes on running
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Containers:
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* `livenessProbe`: Indicates whether the Container is running. If
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the liveness probe fails, the kubelet kills the Container, and the Container
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is subjected to its [restart policy](#restart-policy). If a Container does not
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provide a liveness probe, the default state is `Success`.
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* `readinessProbe`: Indicates whether the Container is ready to service requests.
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If the readiness probe fails, the endpoints controller removes the Pod's IP
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address from the endpoints of all Services that match the Pod. The default
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state of readiness before the initial delay is `Failure`. If a Container does
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not provide a readiness probe, the default state is `Success`.
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-->
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## 容器探针
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[探针](/docs/resources-reference/v1.7/#probe-v1-core) 是由 [kubelet](/docs/admin/kubelet/) 对容器执行的定期诊断。要执行诊断,kubelet 调用由容器实现的 [Handler](https://godoc.org/k8s.io/kubernetes/pkg/api/v1#Handler)。有三种类型的处理程序:
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@@ -158,36 +59,6 @@ Kubelet 可以选择是否执行在容器上运行的两种探针执行和做出
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- `livenessProbe`:指示容器是否正在运行。如果存活探测失败,则 kubelet 会杀死容器,并且容器将受到其 [重启策略](/docs/concepts/workloads/pods/pod-lifecycle/#restart-policy) 的影响。如果容器不提供存活探针,则默认状态为 `Success`。
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- `readinessProbe`:指示容器是否准备好服务请求。如果就绪探测失败,端点控制器将从与 Pod 匹配的所有 Service 的端点中删除该 Pod 的 IP 地址。初始延迟之前的就绪状态默认为 `Failure`。如果容器不提供就绪探针,则默认状态为 `Success`。
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<!--
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### When should you use liveness or readiness probes?
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If the process in your Container is able to crash on its own whenever it
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encounters an issue or becomes unhealthy, you do not necessarily need a liveness
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probe; the kubelet will automatically perform the correct action in accordance
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with the Pod's `restartPolicy`.
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If you'd like your Container to be killed and restarted if a probe fails, then
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specify a liveness probe, and specify a `restartPolicy` of Always or OnFailure.
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If you'd like to start sending traffic to a Pod only when a probe succeeds,
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specify a readiness probe. In this case, the readiness probe might be the same
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as the liveness probe, but the existence of the readiness probe in the spec means
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that the Pod will start without receiving any traffic and only start receiving
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traffic after the probe starts succeeding.
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If you want your Container to be able to take itself down for maintenance, you
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can specify a readiness probe that checks an endpoint specific to readiness that
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is different from the liveness probe.
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Note that if you just want to be able to drain requests when the Pod is deleted,
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you do not necessarily need a readiness probe; on deletion, the Pod automatically
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puts itself into an unready state regardless of whether the readiness probe exists.
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The Pod remains in the unready state while it waits for the Containers in the Pod
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to stop.
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-->
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### 该什么时候使用存活(liveness)和就绪(readiness)探针?
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如果容器中的进程能够在遇到问题或不健康的情况下自行崩溃,则不一定需要存活探针; kubelet 将根据 Pod 的`restartPolicy` 自动执行正确的操作。
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@@ -200,78 +71,14 @@ to stop.
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请注意,如果您只想在 Pod 被删除时能够排除请求,则不一定需要使用就绪探针;在删除 Pod 时,Pod 会自动将自身置于未完成状态,无论就绪探针是否存在。当等待 Pod 中的容器停止时,Pod 仍处于未完成状态。
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<!--
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## Pod and Container status
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For detailed information about Pod Container status, see
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[PodStatus](/docs/resources-reference/v1.6/#podstatus-v1-core)
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and
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[ContainerStatus](/docs/resources-reference/v1.6/#containerstatus-v1-core).
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Note that the information reported as Pod status depends on the current
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[ContainerState](/docs/resources-reference/v1.6/#containerstatus-v1-core).
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-->
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## Pod 和容器状态
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有关 Pod 容器状态的详细信息,请参阅 [PodStatus](/docs/resources-reference/v1.7/#podstatus-v1-core) 和 [ContainerStatus](/docs/resources-reference/v1.7/#containerstatus-v1-core)。请注意,报告的 Pod 状态信息取决于当前的 [ContainerState](/docs/resources-reference/v1.7/#containerstatus-v1-core)。
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<!--
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## Restart policy
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A PodSpec has a `restartPolicy` field with possible values Always, OnFailure,
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and Never. The default value is Always.
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`restartPolicy` applies to all Containers in the Pod. `restartPolicy` only
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refers to restarts of the Containers by the kubelet on the same node. Failed
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Containers that are restarted by the kubelet are restarted with an exponential
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back-off delay (10s, 20s, 40s ...) capped at five minutes, and is reset after ten
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minutes of successful execution. As discussed in the
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[Pods document](/docs/user-guide/pods/#durability-of-pods-or-lack-thereof),
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once bound to a node, a Pod will never be rebound to another node.
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-->
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## 重启策略
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PodSpec 中有一个 `restartPolicy` 字段,可能的值为 Always、OnFailure 和 Never。默认为 Always。 `restartPolicy` 适用于 Pod 中的所有容器。`restartPolicy` 仅指通过同一节点上的 kubelet 重新启动容器。失败的容器由 kubelet 以五分钟为上限的指数退避延迟(10秒,20秒,40秒...)重新启动,并在成功执行十分钟后重置。如 [Pod 文档](/docs/user-guide/pods/#durability-of-pods-or-lack-thereof) 中所述,一旦绑定到一个节点,Pod 将永远不会重新绑定到另一个节点。
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<!--
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## Pod lifetime
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In general, Pods do not disappear until someone destroys them. This might be a
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human or a controller. The only exception to
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this rule is that Pods with a `phase` of Succeeded or Failed for more than some
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duration (determined by the master) will expire and be automatically destroyed.
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Three types of controllers are available:
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- Use a [Job](/docs/concepts/jobs/run-to-completion-finite-workloads/) for Pods that are expected to terminate,
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for example, batch computations. Jobs are appropriate only for Pods with
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`restartPolicy` equal to OnFailure or Never.
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- Use a [ReplicationController](/docs/concepts/workloads/controllers/replicationcontroller/),
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[ReplicaSet](/docs/concepts/workloads/controllers/replicaset/), or
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[Deployment](/docs/concepts/workloads/controllers/deployment/)
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for Pods that are not expected to terminate, for example, web servers.
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ReplicationControllers are appropriate only for Pods with a `restartPolicy` of
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Always.
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- Use a [DaemonSet](/docs/concepts/workloads/controllers/daemonset/) for Pods that need to run one per
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machine, because they provide a machine-specific system service.
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All three types of controllers contain a PodTemplate. It
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is recommended to create the appropriate controller and let
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it create Pods, rather than directly create Pods yourself. That is because Pods
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alone are not resilient to machine failures, but controllers are.
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If a node dies or is disconnected from the rest of the cluster, Kubernetes
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applies a policy for setting the `phase` of all Pods on the lost node to Failed.
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-->
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## Pod 的生命
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一般来说,Pod 不会消失,直到人为销毁他们。这可能是一个人或控制器。这个规则的唯一例外是成功或失败的 `phase` 超过一段时间(由 master 确定)的Pod将过期并被自动销毁。
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@@ -288,17 +95,6 @@ applies a policy for setting the `phase` of all Pods on the lost node to Failed.
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如果节点死亡或与集群的其余部分断开连接,则 Kubernetes 将应用一个策略将丢失节点上的所有 Pod 的 `phase` 设置为 Failed。
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<!--
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## Examples
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### Advanced liveness probe example
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Liveness probes are executed by the kubelet, so all requests are made in the
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kubelet network namespace.
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-->
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## 示例
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### 高级 liveness 探针示例
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@@ -333,69 +129,6 @@ spec:
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name: liveness
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```
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<!--
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### Example states
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* Pod is running and has one Container. Container exits with success.
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* Log completion event.
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* If `restartPolicy` is:
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* Always: Restart Container; Pod `phase` stays Running.
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* OnFailure: Pod `phase` becomes Succeeded.
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* Never: Pod `phase` becomes Succeeded.
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* Pod is running and has one Container. Container exits with failure.
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* Log failure event.
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* If `restartPolicy` is:
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* Always: Restart Container; Pod `phase` stays Running.
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* OnFailure: Restart Container; Pod `phase` stays Running.
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* Never: Pod `phase` becomes Failed.
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* Pod is running and has two Containers. Container 1 exits with failure.
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* Log failure event.
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* If `restartPolicy` is:
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* Always: Restart Container; Pod `phase` stays Running.
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* OnFailure: Restart Container; Pod `phase` stays Running.
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* Never: Do not restart Container; Pod `phase` stays Running.
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* If Container 1 is not running, and Container 2 exits:
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* Log failure event.
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* If `restartPolicy` is:
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* Always: Restart Container; Pod `phase` stays Running.
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* OnFailure: Restart Container; Pod `phase` stays Running.
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* Never: Pod `phase` becomes Failed.
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* Pod is running and has one Container. Container runs out of memory.
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* Container terminates in failure.
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* Log OOM event.
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* If `restartPolicy` is:
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* Always: Restart Container; Pod `phase` stays Running.
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* OnFailure: Restart Container; Pod `phase` stays Running.
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* Never: Log failure event; Pod `phase` becomes Failed.
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* Pod is running, and a disk dies.
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* Kill all Containers.
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* Log appropriate event.
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* Pod `phase` becomes Failed.
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* If running under a controller, Pod is recreated elsewhere.
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* Pod is running, and its node is segmented out.
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* Node controller waits for timeout.
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* Node controller sets Pod `phase` to Failed.
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* If running under a controller, Pod is recreated elsewhere.
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{% endcapture %}
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||||
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{% capture whatsnext %}
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* Get hands-on experience
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[attaching handlers to Container lifecycle events](/docs/tasks/configure-pod-container/attach-handler-lifecycle-event/).
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* Get hands-on experience
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[configuring liveness and readiness probes](/docs/tasks/configure-pod-container/configure-liveness-readiness-probes/).
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* Learn more about [Container lifecycle hooks](/docs/concepts/containers/container-lifecycle-hooks/).
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-->
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### 状态示例
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||||
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- Pod 中只有一个容器并且正在运行。容器成功退出。
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||||
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Reference in New Issue
Block a user