zh_trans:update run-application/rolling-update-replication-controller.md (#11479)

2018-12-03 22:43:03 +08:00
parent 13953625e4
commit 3baab1abac
1 changed files with 280 additions and 3 deletions
@@ -1,32 +1,81 @@
 ---
-approvers:
+reviewers:
 - janetkuo
 title: 基于Replication Controller执行滚动升级
+content_template: templates/concept
+weight: 80
 ---
-
-{{< toc >}}
+<!-- 
+---
+reviewers:
+- janetkuo
+title: Perform Rolling Update Using a Replication Controller
+content_template: templates/concept
+weight: 80
+--- 
+-->

 ## 概述

 **注**: 创建副本应用的首选方法是使用[Deployment](/docs/api-reference/{{< param "version" >}}/#deployment-v1beta1-apps)，Deployment使用[ReplicaSet](/docs/api-reference/{{< param "version" >}}/#replicaset-v1beta1-extensions)来进行副本控制。
 更多信息, 查看[使用Deployment运行一个无状态应用](/docs/tasks/run-application/run-stateless-application-deployment/)。

+<!-- 
+{{< note >}}
+**Note**: The preferred way to create a replicated application is to use a
+[Deployment](/docs/reference/generated/kubernetes-api/{{< param "version" >}}/#deployment-v1-apps),
+which in turn uses a
+[ReplicaSet](/docs/reference/generated/kubernetes-api/{{< param "version" >}}/#replicaset-v1-apps).
+For more information, see
+[Running a Stateless Application Using a Deployment](/docs/tasks/run-application/run-stateless-application-deployment/).
+{{< /note >}}
+-->
+
 为了在更新服务的同时不中断业务， `kubectl` 支持['滚动更新'](/docs/user-guide/kubectl/v1.6/#rolling-update)，它一次更新一个pod，而不是同时停止整个服务。 有关更多信息，请参阅 [滚动更新设计文档](https://git.k8s.io/community/contributors/design-proposals/cli/simple-rolling-update.md) 和 [滚动更新示例](/docs/tasks/run-application/rolling-update-replication-controller/)。
+<!-- 
+To update a service without an outage, `kubectl` supports what is called [rolling update](/docs/reference/generated/kubectl/kubectl-commands/#rolling-update), which updates one pod at a time, rather than taking down the entire service at the same time. See the [rolling update design document](https://git.k8s.io/community/contributors/design-proposals/cli/simple-rolling-update.md) for more information.
+-->

 请注意， `kubectl rolling-update` 仅支持Replication Controllers。 但是，如果使用Replication Controllers部署应用，请考虑将其切换到[Deployments](/docs/concepts/workloads/controllers/deployment/). Deployment是一种被推荐使用的更高级别的控制器，它可以对应用进行声明性的自动滚动更新。 如果您仍然希望保留您的Replication Controllers并使用 `kubectl rolling-update`进行滚动更新， 请继续往下阅读：
+<!-- 
+Note that `kubectl rolling-update` only supports Replication Controllers. However, if you deploy applications with Replication Controllers,
+consider switching them to [Deployments](/docs/concepts/workloads/controllers/deployment/). A Deployment is a higher-level controller that automates rolling updates
+of applications declaratively, and therefore is recommended. If you still want to keep your Replication Controllers and use `kubectl rolling-update`, keep reading:
+-->

 滚动更新可以对replication controller所管理的Pod的配置进行变更，变更可以通过一个新的配置文件来进行，或者，如果只更新镜像，则可以直接指定新的容器镜像。
+<!--
+A rolling update applies changes to the configuration of pods being managed by
+a replication controller. The changes can be passed as a new replication
+controller configuration file; or, if only updating the image, a new container
+image can be specified directly.
+-->

 滚动更新的工作流程：
+<!--
+A rolling update works by:
+-->

 1. 通过新的配置创建一个replication controller
 2. 在新的控制器上增加副本数，在旧的上面减少副本数，直到副本数达到期望值
 3. 删除之前的replication controller
+<!--
+1. Creating a new replication controller with the updated configuration.
+2. Increasing/decreasing the replica count on the new and old controllers until
+   the correct number of replicas is reached.
+3. Deleting the original replication controller.
+-->

 使用`kubectl rolling-update`命令来进行滚动更新：

    $ kubectl rolling-update NAME \
        ([NEW_NAME] --image=IMAGE | -f FILE)
+<!--
+Rolling updates are initiated with the `kubectl rolling-update` command:
+
+    $ kubectl rolling-update NAME \
+        ([NEW_NAME] --image=IMAGE | -f FILE)
+-->

 ## 通过配置文件更新

@@ -43,6 +92,25 @@ title: 基于Replication Controller执行滚动升级
 * `metadata.namespace`字段必须相同

 Replication Controllers的配置文件详细介绍见[创建Replication Controllers](/docs/tutorials/stateless-application/run-stateless-ap-replication-controller/).
+<!--
+## Passing a configuration file
+
+To initiate a rolling update using a configuration file, pass the new file to
+`kubectl rolling-update`:
+
+    $ kubectl rolling-update NAME -f FILE
+
+The configuration file must:
+
+* Specify a different `metadata.name` value.
+
+* Overwrite at least one common label in its `spec.selector` field.
+
+* Use the same `metadata.namespace`.
+
+Replication controller configuration files are described in
+[Creating Replication Controllers](/docs/tutorials/stateless-application/run-stateless-ap-replication-controller/).
+-->

 ### 示例

@@ -51,6 +119,15 @@ Replication Controllers的配置文件详细介绍见[创建Replication Controll

    // 将frontend-v2.json数据传到标准输入来更新frontend-v1的pods
    $ cat frontend-v2.json | kubectl rolling-update frontend-v1 -f -
+<!--
+### Examples
+
+    // Update pods of frontend-v1 using new replication controller data in frontend-v2.json.
+    $ kubectl rolling-update frontend-v1 -f frontend-v2.json
+
+    // Update pods of frontend-v1 using JSON data passed into stdin.
+    $ cat frontend-v2.json | kubectl rolling-update frontend-v1 -f -
+-->

 ## 更新容器镜像

@@ -64,6 +141,28 @@ Replication Controllers的配置文件详细介绍见[创建Replication Controll

 如果`IMAGE:TAG` 和当前值相同，更新就会失败。 因此，我们建议使用版本号来作为标签，而不是使用 `:latest`。从一个 `image:latest`镜像升级到一个新的 `image:latest` 镜像将会失败，即使这两个镜像不是相同的。
 所以，我们不建议使用 `:latest` 来作为标签，详细信息见[最佳配置实践](/docs/concepts/configuration/overview/#container-images) 。
+<!--
+## Updating the container image
+
+To update only the container image, pass a new image name and tag with the
+`--image` flag and (optionally) a new controller name:
+
+    $ kubectl rolling-update NAME [NEW_NAME] --image=IMAGE:TAG
+
+The `--image` flag is only supported for single-container pods. Specifying
+`--image` with multi-container pods returns an error.
+
+If no `NEW_NAME` is specified, a new replication controller is created with
+a temporary name. Once the rollout is complete, the old controller is deleted,
+and the new controller is updated to use the original name.
+
+The update will fail if `IMAGE:TAG` is identical to the
+current value. For this reason, we recommend the use of versioned tags as
+opposed to values such as `:latest`. Doing a rolling update from `image:latest`
+to a new `image:latest` will fail, even if the image at that tag has changed.
+Moreover, the use of `:latest` is not recommended, see
+[Best Practices for Configuration](/docs/concepts/configuration/overview/#container-images) for more information.
+-->

 ### 示例

@@ -72,6 +171,15 @@ Replication Controllers的配置文件详细介绍见[创建Replication Controll

    // 更新frontend的pods，不更改replication controller的名称
    $ kubectl rolling-update frontend --image=image:v2
+<!--
+### Examples
+
+    // Update the pods of frontend-v1 to frontend-v2
+    $ kubectl rolling-update frontend-v1 frontend-v2 --image=image:v2
+
+    // Update the pods of frontend, keeping the replication controller name
+    $ kubectl rolling-update frontend --image=image:v2
+-->

 ## 必选和可选字段

@@ -98,6 +206,46 @@ Replication Controllers的配置文件详细介绍见[创建Replication Controll
 * `--update-period DURATION`: 更新两个pod之间等待的时间，默认值是`1m0s`。有效单位如`--poll-interval`所述。

 有关`kubectl rolling-update`命令的更多信息见[`kubectl`参考](/docs/user-guide/kubectl/v1.6/#rolling-update).
+<!--
+## Required and optional fields
+
+Required fields are:
+
+* `NAME`: The name of the replication controller to update.
+
+as well as either:
+
+* `-f FILE`: A replication controller configuration file, in either JSON or
+  YAML format. The configuration file must specify a new top-level `id` value
+  and include at least one of the existing `spec.selector` key:value pairs.
+  See the
+  [Run Stateless AP Replication Controller](/docs/tutorials/stateless-application/run-stateless-ap-replication-controller/#replication-controller-configuration-file)
+  page for details.
+<br>
+<br>
+    or:
+<br>
+<br>
+* `--image IMAGE:TAG`: The name and tag of the image to update to. Must be
+  different than the current image:tag currently specified.
+
+Optional fields are:
+
+* `NEW_NAME`: Only used in conjunction with `--image` (not with `-f FILE`). The
+  name to assign to the new replication controller.
+* `--poll-interval DURATION`: The time between polling the controller status
+  after update. Valid units are `ns` (nanoseconds), `us` or `µs` (microseconds),
+  `ms` (milliseconds), `s` (seconds), `m` (minutes), or `h` (hours). Units can
+  be combined (e.g. `1m30s`). The default is `3s`.
+* `--timeout DURATION`: The maximum time to wait for the controller to update a
+  pod before exiting. Default is `5m0s`. Valid units are as described for
+  `--poll-interval` above.
+* `--update-period DURATION`: The time to wait between updating pods. Default
+  is `1m0s`. Valid units are as described for `--poll-interval` above.
+
+Additional information about the `kubectl rolling-update` command is available
+from the [`kubectl` reference](/docs/reference/generated/kubectl/kubectl-commands/#rolling-update).
+-->

 ## 实践

@@ -214,6 +362,123 @@ Scaling my-nginx-v4 up to 5
 Update succeeded. Deleting old controller: my-nginx
 replicationcontroller "my-nginx-v4" rolling updated
 ```
+<!--
+## Walkthrough
+
+Let's say you were running version 1.7.9 of nginx:
+
+```yaml
+apiVersion: v1
+kind: ReplicationController
+metadata:
+  name: my-nginx
+spec:
+  replicas: 5
+  template:
+    metadata:
+      labels:
+        app: nginx
+    spec:
+      containers:
+      - name: nginx
+        image: nginx:1.7.9
+        ports:
+        - containerPort: 80
+```
+
+To update to version 1.9.1, you can use [`kubectl rolling-update --image`](https://git.k8s.io/community/contributors/design-proposals/cli/simple-rolling-update.md) to specify the new image:
+
+```shell
+$ kubectl rolling-update my-nginx --image=nginx:1.9.1
+Created my-nginx-ccba8fbd8cc8160970f63f9a2696fc46
+```
+
+In another window, you can see that `kubectl` added a `deployment` label to the pods, whose value is a hash of the configuration, to distinguish the new pods from the old:
+
+```shell
+$ kubectl get pods -l app=nginx -L deployment
+NAME                                              READY     STATUS    RESTARTS   AGE       DEPLOYMENT
+my-nginx-ccba8fbd8cc8160970f63f9a2696fc46-k156z   1/1       Running   0          1m        ccba8fbd8cc8160970f63f9a2696fc46
+my-nginx-ccba8fbd8cc8160970f63f9a2696fc46-v95yh   1/1       Running   0          35s       ccba8fbd8cc8160970f63f9a2696fc46
+my-nginx-divi2                                    1/1       Running   0          2h        2d1d7a8f682934a254002b56404b813e
+my-nginx-o0ef1                                    1/1       Running   0          2h        2d1d7a8f682934a254002b56404b813e
+my-nginx-q6all                                    1/1       Running   0          8m        2d1d7a8f682934a254002b56404b813e
+```
+
+`kubectl rolling-update` reports progress as it progresses:
+
+```
+Scaling up my-nginx-ccba8fbd8cc8160970f63f9a2696fc46 from 0 to 3, scaling down my-nginx from 3 to 0 (keep 3 pods available, don't exceed 4 pods)
+Scaling my-nginx-ccba8fbd8cc8160970f63f9a2696fc46 up to 1
+Scaling my-nginx down to 2
+Scaling my-nginx-ccba8fbd8cc8160970f63f9a2696fc46 up to 2
+Scaling my-nginx down to 1
+Scaling my-nginx-ccba8fbd8cc8160970f63f9a2696fc46 up to 3
+Scaling my-nginx down to 0
+Update succeeded. Deleting old controller: my-nginx
+Renaming my-nginx-ccba8fbd8cc8160970f63f9a2696fc46 to my-nginx
+replicationcontroller "my-nginx" rolling updated
+```
+
+If you encounter a problem, you can stop the rolling update midway and revert to the previous version using `--rollback`:
+
+```shell
+$ kubectl rolling-update my-nginx --rollback
+Setting "my-nginx" replicas to 1
+Continuing update with existing controller my-nginx.
+Scaling up nginx from 1 to 1, scaling down my-nginx-ccba8fbd8cc8160970f63f9a2696fc46 from 1 to 0 (keep 1 pods available, don't exceed 2 pods)
+Scaling my-nginx-ccba8fbd8cc8160970f63f9a2696fc46 down to 0
+Update succeeded. Deleting my-nginx-ccba8fbd8cc8160970f63f9a2696fc46
+replicationcontroller "my-nginx" rolling updated
+```
+
+This is one example where the immutability of containers is a huge asset.
+
+If you need to update more than just the image (e.g., command arguments, environment variables), you can create a new replication controller, with a new name and distinguishing label value, such as:
+
+```yaml
+apiVersion: v1
+kind: ReplicationController
+metadata:
+  name: my-nginx-v4
+spec:
+  replicas: 5
+  selector:
+    app: nginx
+    deployment: v4
+  template:
+    metadata:
+      labels:
+        app: nginx
+        deployment: v4
+    spec:
+      containers:
+      - name: nginx
+        image: nginx:1.9.2
+        args: ["nginx", "-T"]
+        ports:
+        - containerPort: 80
+```
+
+and roll it out:
+
+```shell
+$ kubectl rolling-update my-nginx -f ./nginx-rc.yaml
+Created my-nginx-v4
+Scaling up my-nginx-v4 from 0 to 5, scaling down my-nginx from 4 to 0 (keep 4 pods available, don't exceed 5 pods)
+Scaling my-nginx-v4 up to 1
+Scaling my-nginx down to 3
+Scaling my-nginx-v4 up to 2
+Scaling my-nginx down to 2
+Scaling my-nginx-v4 up to 3
+Scaling my-nginx down to 1
+Scaling my-nginx-v4 up to 4
+Scaling my-nginx down to 0
+Scaling my-nginx-v4 up to 5
+Update succeeded. Deleting old controller: my-nginx
+replicationcontroller "my-nginx-v4" rolling updated
+```
+-->

 ## 故障分析

@@ -222,3 +487,15 @@ replicationcontroller "my-nginx-v4" rolling updated
 如果更新失败，可以尝试使用同样的命令来继续更新过程。

 在尝试更新之前如果需要回滚到之前的状态，可在之前的命令后面添加`--rollback=true`参数，这将回退所有的更改。
+<!--
+## Troubleshooting
+
+If the `timeout` duration is reached during a rolling update, the operation will
+fail with some pods belonging to the new replication controller, and some to the
+original controller.
+
+To continue the update from where it failed, retry using the same command.
+
+To roll back to the original state before the attempted update, append the
+`--rollback=true` flag to the original command. This will revert all changes.
+-->