[zh] sync /reference/node/node-status.md
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---
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content_type: reference
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title: 节点状态
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weight: 80
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---
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<!--
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content_type: reference
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title: Node Status
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weight: 80
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-->
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<!-- overview -->
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<!--
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The status of a [node](/docs/concepts/architecture/nodes/) in Kubernetes is a critical
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aspect of managing a Kubernetes cluster. In this article, we'll cover the basics of
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monitoring and maintaining node status to ensure a healthy and stable cluster.
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-->
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在 Kubernetes 中，[节点](/zh-cn/docs/concepts/architecture/nodes/)的状态是管理 Kubernetes
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集群的一个关键方面。在本文中，我们将简要介绍如何监控和维护节点状态以确保集群的健康和稳定。
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<!--
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## Node status fields
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A Node's status contains the following information:
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* [Addresses](#addresses)
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* [Conditions](#condition)
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* [Capacity and Allocatable](#capacity)
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* [Info](#info)
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-->
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## 节点状态字段 {#node-status-fields}
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一个节点的状态包含以下信息:
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* [地址（Addresses）](#addresses)
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* [状况（Condition）](#condition)
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* [容量与可分配（Capacity）](#capacity)
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* [信息（Info）](#info)
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<!--
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You can use `kubectl` to view a Node's status and other details:
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```shell
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kubectl describe node <insert-node-name-here>
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```
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Each section of the output is described below.
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-->
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你可以使用 `kubectl` 来查看节点状态和其他细节信息：
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```shell
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kubectl describe node <节点名称>
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```
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下面对输出的每个部分进行详细描述。
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<!--
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## Addresses
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The usage of these fields varies depending on your cloud provider or bare metal configuration.
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-->
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### 地址 {#addresses}
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这些字段的用法取决于你的云服务商或者物理机配置。
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<!--
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* HostName: The hostname as reported by the node's kernel. Can be overridden via the kubelet
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`--hostname-override` parameter.
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* ExternalIP: Typically the IP address of the node that is externally routable (available from
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outside the cluster).
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* InternalIP: Typically the IP address of the node that is routable only within the cluster.
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-->
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* HostName：由节点的内核报告。可以通过 kubelet 的 `--hostname-override` 参数覆盖。
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* ExternalIP：通常是节点的可外部路由（从集群外可访问）的 IP 地址。
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* InternalIP：通常是节点的仅可在集群内部路由的 IP 地址。
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<!--
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## Conditions {#condition}
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The `conditions` field describes the status of all `Running` nodes. Examples of conditions include:
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-->
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### 状况 {#condition}
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`conditions` 字段描述了所有 `Running` 节点的状况。状况的示例包括：
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<!--
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{{< table caption = "Node conditions, and a description of when each condition applies." >}}
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| Node Condition | Description |
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|----------------------|-------------|
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| `Ready` | `True` if the node is healthy and ready to accept pods, `False` if the node is not healthy and is not accepting pods, and `Unknown` if the node controller has not heard from the node in the last `node-monitor-grace-period` (default is 40 seconds) |
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| `DiskPressure` | `True` if pressure exists on the disk size—that is, if the disk capacity is low; otherwise `False` |
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| `MemoryPressure` | `True` if pressure exists on the node memory—that is, if the node memory is low; otherwise `False` |
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| `PIDPressure` | `True` if pressure exists on the processes—that is, if there are too many processes on the node; otherwise `False` |
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| `NetworkUnavailable` | `True` if the network for the node is not correctly configured, otherwise `False` |
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{{< /table >}}
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-->
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{{< table caption = "节点状况及每种状况适用场景的描述" >}}
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| 节点状况 | 描述 |
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|----------------|-------------|
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| `Ready` | 如节点是健康的并已经准备好接收 Pod 则为 `True`；`False` 表示节点不健康而且不能接收 Pod；`Unknown` 表示节点控制器在最近 `node-monitor-grace-period` 期间（默认 40 秒）没有收到节点的消息 |
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| `DiskPressure` | `True` 表示节点存在磁盘空间压力，即磁盘可用量低，否则为 `False` |
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| `MemoryPressure` | `True` 表示节点存在内存压力，即节点内存可用量低，否则为 `False` |
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| `PIDPressure` | `True` 表示节点存在进程压力，即节点上进程过多；否则为 `False` |
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| `NetworkUnavailable` | `True` 表示节点网络配置不正确；否则为 `False` |
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{{< /table >}}
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{{< note >}}
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<!--
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If you use command-line tools to print details of a cordoned Node, the Condition includes
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`SchedulingDisabled`. `SchedulingDisabled` is not a Condition in the Kubernetes API; instead,
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cordoned nodes are marked Unschedulable in their spec.
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-->
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如果使用命令行工具来打印已保护（Cordoned）节点的细节，其中的 Condition 字段可能包括
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`SchedulingDisabled`。`SchedulingDisabled` 不是 Kubernetes API 中定义的
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Condition，被保护起来的节点在其规约中被标记为不可调度（Unschedulable）。
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{{< /note >}}
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<!--
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In the Kubernetes API, a node's condition is represented as part of the `.status`
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of the Node resource. For example, the following JSON structure describes a healthy node:
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-->
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在 Kubernetes API 中，节点的状况表示节点资源中 `.status` 的一部分。
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例如，以下 JSON 结构描述了一个健康节点：
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```json
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"conditions": [
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{
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"type": "Ready",
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"status": "True",
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"reason": "KubeletReady",
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"message": "kubelet is posting ready status",
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"lastHeartbeatTime": "2019-06-05T18:38:35Z",
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"lastTransitionTime": "2019-06-05T11:41:27Z"
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}
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]
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```
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<!--
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When problems occur on nodes, the Kubernetes control plane automatically creates
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[taints](/docs/concepts/scheduling-eviction/taint-and-toleration/) that match the conditions
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affecting the node. An example of this is when the `status` of the Ready condition
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remains `Unknown` or `False` for longer than the kube-controller-manager's `NodeMonitorGracePeriod`,
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which defaults to 40 seconds. This will cause either an `node.kubernetes.io/unreachable` taint, for an `Unknown` status,
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or a `node.kubernetes.io/not-ready` taint, for a `False` status, to be added to the Node.
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-->
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当节点上出现问题时，Kubernetes 控制面会自动创建与影响节点的状况对应的
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[污点](/zh-cn/docs/concepts/scheduling-eviction/taint-and-toleration/)。
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例如当 Ready 状况的 `status` 保持 `Unknown` 或 `False` 的时间长于
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kube-controller-manager 的 `NodeMonitorGracePeriod`（默认为 40 秒）时，
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会造成 `Unknown` 状态下为节点添加 `node.kubernetes.io/unreachable` 污点或在
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`False` 状态下为节点添加 `node.kubernetes.io/not-ready` 污点。
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<!--
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These taints affect pending pods as the scheduler takes the Node's taints into consideration when
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assigning a pod to a Node. Existing pods scheduled to the node may be evicted due to the application
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of `NoExecute` taints. Pods may also have {{< glossary_tooltip text="tolerations" term_id="toleration" >}} that let
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them schedule to and continue running on a Node even though it has a specific taint.
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-->
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这些污点会影响悬决的 Pod，因为调度器在将 Pod 分配到节点时会考虑节点的污点。
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已调度到节点的当前 Pod 可能会由于施加的 `NoExecute` 污点被驱逐。
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Pod 还可以设置{{< glossary_tooltip text="容忍度" term_id="toleration" >}}，
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使得这些 Pod 仍然能够调度到且继续运行在设置了特定污点的节点上。
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<!--
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See [Taint Based Evictions](/docs/concepts/scheduling-eviction/taint-and-toleration/#taint-based-evictions) and
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[Taint Nodes by Condition](/docs/concepts/scheduling-eviction/taint-and-toleration/#taint-nodes-by-condition)
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for more details.
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-->
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进一步的细节可参阅[基于污点的驱逐](/zh-cn/docs/concepts/scheduling-eviction/taint-and-toleration/#taint-based-evictions)
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和[根据状况为节点设置污点](/zh-cn/docs/concepts/scheduling-eviction/taint-and-toleration/#taint-nodes-by-condition)。
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<!--
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## Capacity and Allocatable {#capacity}
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Describes the resources available on the node: CPU, memory, and the maximum
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number of pods that can be scheduled onto the node.
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-->
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### 容量（Capacity）与可分配（Allocatable） {#capacity}
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这两个值描述节点上的可用资源：CPU、内存和可以调度到节点上的 Pod 的个数上限。
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<!--
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The fields in the capacity block indicate the total amount of resources that a
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Node has. The allocatable block indicates the amount of resources on a
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Node that is available to be consumed by normal Pods.
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-->
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`capacity` 块中的字段标示节点拥有的资源总量。
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`allocatable` 块指示节点上可供普通 Pod 使用的资源量。
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<!--
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You may read more about capacity and allocatable resources while learning how
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to [reserve compute resources](/docs/tasks/administer-cluster/reserve-compute-resources/#node-allocatable)
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on a Node.
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-->
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你可以通过学习如何在节点上[预留计算资源](/zh-cn/docs/tasks/administer-cluster/reserve-compute-resources/#node-allocatable)
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来进一步了解有关容量和可分配资源的信息。
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<!--
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## Info
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Describes general information about the node, such as kernel version, Kubernetes
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version (kubelet and kube-proxy version), container runtime details, and which
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operating system the node uses.
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The kubelet gathers this information from the node and publishes it into
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the Kubernetes API.
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-->
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### 信息（Info） {#info}
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Info 指的是节点的一般信息，如内核版本、Kubernetes 版本（`kubelet` 和 `kube-proxy` 版本）、
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容器运行时详细信息，以及节点使用的操作系统。
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`kubelet` 从节点收集这些信息并将其发布到 Kubernetes API。
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<!--
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## Heartbeats
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Heartbeats, sent by Kubernetes nodes, help your cluster determine the
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availability of each node, and to take action when failures are detected.
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-->
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## 心跳 {#heartbeats}
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Kubernetes 节点发送的心跳帮助你的集群确定每个节点的可用性，并在检测到故障时采取行动。
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<!--
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For nodes there are two forms of heartbeats:
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* updates to the `.status` of a Node
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* [Lease](/docs/concepts/architecture/leases/) objects
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within the `kube-node-lease`
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{{< glossary_tooltip term_id="namespace" text="namespace">}}.
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Each Node has an associated Lease object.
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-->
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对于节点，有两种形式的心跳：
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* 更新节点的 `.status`
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* `kube-node-lease` {{<glossary_tooltip term_id="namespace" text="名字空间">}}中的
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[Lease（租约）](/zh-cn/docs/concepts/architecture/leases/)对象。
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每个节点都有一个关联的 Lease 对象。
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<!--
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Compared to updates to `.status` of a Node, a Lease is a lightweight resource.
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Using Leases for heartbeats reduces the performance impact of these updates
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for large clusters.
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The kubelet is responsible for creating and updating the `.status` of Nodes,
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and for updating their related Leases.
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-->
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与节点的 `.status` 更新相比，Lease 是一种轻量级资源。
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使用 Lease 来表达心跳在大型集群中可以减少这些更新对性能的影响。
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kubelet 负责创建和更新节点的 `.status`，以及更新它们对应的 Lease。
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<!--
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- The kubelet updates the node's `.status` either when there is change in status
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or if there has been no update for a configured interval. The default interval
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for `.status` updates to Nodes is 5 minutes, which is much longer than the 40
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second default timeout for unreachable nodes.
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- The kubelet creates and then updates its Lease object every 10 seconds
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(the default update interval). Lease updates occur independently from
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updates to the Node's `.status`. If the Lease update fails, the kubelet retries,
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using exponential backoff that starts at 200 milliseconds and capped at 7 seconds.
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-->
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- 当节点状态发生变化时，或者在配置的时间间隔内没有更新事件时，kubelet 会更新 `.status`。
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`.status` 更新的默认间隔为 5 分钟（比节点不可达事件的 40 秒默认超时时间长很多）。
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- `kubelet` 会创建并每 10 秒（默认更新间隔时间）更新 Lease 对象。
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Lease 的更新独立于节点的 `.status` 更新而发生。
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如果 Lease 的更新操作失败，kubelet 会采用指数回退机制，从 200 毫秒开始重试，
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最长重试间隔为 7 秒钟。
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