376 lines
13 KiB
Markdown
376 lines
13 KiB
Markdown
---
|
||
title: 配置 Pod 以使用 PersistentVolume 作为存储
|
||
content_template: templates/task
|
||
weight: 60
|
||
---
|
||
|
||
<!--
|
||
---
|
||
title: Configure a Pod to Use a PersistentVolume for Storage
|
||
content_template: templates/task
|
||
weight: 60
|
||
---
|
||
-->
|
||
|
||
{{% capture overview %}}
|
||
|
||
<!--
|
||
This page shows how to configure a Pod to use a PersistentVolumeClaim for storage.
|
||
Here is a summary of the process:
|
||
|
||
1. A cluster administrator creates a PersistentVolume that is backed by physical
|
||
storage. The administrator does not associate the volume with any Pod.
|
||
|
||
1. A cluster user creates a PersistentVolumeClaim, which gets automatically
|
||
bound to a suitable PersistentVolume.
|
||
|
||
1. The user creates a Pod that uses the PersistentVolumeClaim as storage.
|
||
-->
|
||
|
||
本文介绍如何配置 Pod 使用 PersistentVolumeClaim 作为存储。
|
||
以下是该过程的总结：
|
||
|
||
1. 集群管理员创建由物理存储支持的 PersistentVolume。管理员不将卷与任何 Pod 关联。
|
||
|
||
1. 群集用户创建一个 PersistentVolumeClaim，它将自动绑定到合适的 PersistentVolume。
|
||
|
||
1. 用户创建一个使用 PersistentVolumeClaim 作为存储的 Pod。
|
||
|
||
{{% /capture %}}
|
||
|
||
{{% capture prerequisites %}}
|
||
|
||
<!--
|
||
* You need to have a Kubernetes cluster that has only one Node, and the kubectl
|
||
command-line tool must be configured to communicate with your cluster. If you
|
||
do not already have a single-node cluster, you can create one by using
|
||
[Minikube](/docs/getting-started-guides/minikube).
|
||
|
||
* Familiarize yourself with the material in
|
||
[Persistent Volumes](/docs/concepts/storage/persistent-volumes/).
|
||
-->
|
||
|
||
* 您需要一个包含单个节点的 Kubernetes 集群，并且必须配置 kubectl 命令行工具以便与集群交互。
|
||
如果还没有单节点集群，可以使用 [Minikube](/docs/getting-started-guides/minikube) 创建一个。
|
||
|
||
* 熟悉[持久卷](/docs/concepts/storage/persistent-volumes/)中的材料。
|
||
|
||
{{% /capture %}}
|
||
|
||
{{% capture steps %}}
|
||
|
||
<!--
|
||
## Create an index.html file on your Node
|
||
|
||
Open a shell to the Node in your cluster. How you open a shell depends on how
|
||
you set up your cluster. For example, if you are using Minikube, you can open a
|
||
shell to your Node by entering `minikube ssh`.
|
||
|
||
In your shell, create a `/mnt/data` directory:
|
||
-->
|
||
|
||
## 在你的节点上创建一个 index.html 文件
|
||
|
||
打开集群中节点的一个 shell。
|
||
如何打开 shell 取决于集群的设置。
|
||
例如，如果您正在使用 Minikube，那么可以通过输入 `minikube ssh` 来打开节点的 shell。
|
||
|
||
在 shell 中，创建一个 `/mnt/data` 目录：
|
||
|
||
mkdir /mnt/data
|
||
|
||
<!--
|
||
In the `/mnt/data` directory, create an `index.html` file:
|
||
-->
|
||
|
||
在 `/mnt/data` 目录中创建一个 index.html 文件：
|
||
|
||
echo 'Hello from Kubernetes storage' > /mnt/data/index.html
|
||
|
||
<!--
|
||
## Create a PersistentVolume
|
||
|
||
In this exercise, you create a *hostPath* PersistentVolume. Kubernetes supports
|
||
hostPath for development and testing on a single-node cluster. A hostPath
|
||
PersistentVolume uses a file or directory on the Node to emulate network-attached storage.
|
||
-->
|
||
|
||
## 创建 PersistentVolume
|
||
|
||
在本练习中，您将创建一个 *hostPath* 类型的 PersistentVolume。
|
||
Kubernetes 支持用于在单节点集群上开发和测试的 hostPath 类型的 PersistentVolume。
|
||
hostPath 类型的 PersistentVolume 使用节点上的文件或目录来模拟附带网络的存储。
|
||
|
||
<!--
|
||
In a production cluster, you would not use hostPath. Instead a cluster administrator
|
||
would provision a network resource like a Google Compute Engine persistent disk,
|
||
an NFS share, or an Amazon Elastic Block Store volume. Cluster administrators can also
|
||
use [StorageClasses](/docs/reference/generated/kubernetes-api/{{< param "version" >}}/#storageclass-v1-storage)
|
||
to set up
|
||
[dynamic provisioning](https://kubernetes.io/blog/2016/10/dynamic-provisioning-and-storage-in-kubernetes).
|
||
|
||
Here is the configuration file for the hostPath PersistentVolume:
|
||
-->
|
||
|
||
在生产集群中，您不会使用 hostPath。集群管理员会提供网络存储资源，比如 Google Compute Engine 持久盘卷、NFS 共享卷或 Amazon Elastic Block Store 卷。
|
||
集群管理员还可以使用 [StorageClasses](/docs/reference/generated/kubernetes-api/{{< param "version" >}}/#storageclass-v1-storage) 来设置[动态提供存储](https://kubernetes.io/blog/2016/10/dynamic-provisioning-and-storage-in-kubernetes)。
|
||
|
||
下面是 hostPath PersistentVolume 的配置文件：
|
||
|
||
{{< codenew file="pods/storage/pv-volume.yaml" >}}
|
||
|
||
<!--
|
||
The configuration file specifies that the volume is at `/mnt/data` on the
|
||
cluster's Node. The configuration also specifies a size of 10 gibibytes and
|
||
an access mode of `ReadWriteOnce`, which means the volume can be mounted as
|
||
read-write by a single Node. It defines the [StorageClass name](/docs/concepts/storage/persistent-volumes/#class)
|
||
`manual` for the PersistentVolume, which will be used to bind
|
||
PersistentVolumeClaim requests to this PersistentVolume.
|
||
|
||
Create the PersistentVolume:
|
||
-->
|
||
|
||
配置文件指定了该卷位于集群节点上的 `/mnt/data` 目录。
|
||
该配置还指定了 10 吉比特的卷大小和 `ReadWriteOnce` 的访问模式，这意味着该卷可以在单个节点上以读写方式挂载。
|
||
它为 PersistentVolume 定义了 [StorageClass 名称](/docs/concepts/storage/persistent-volumes/#class) 为 `manual`，StorageClass 名称用来将 PersistentVolumeClaim 请求绑定到该 PersistentVolume。
|
||
|
||
创建 PersistentVolume：
|
||
|
||
kubectl create -f https://k8s.io/examples/pods/storage/pv-volume.yaml
|
||
|
||
<!--
|
||
View information about the PersistentVolume:
|
||
-->
|
||
|
||
查看 PersistentVolume 的信息：
|
||
|
||
kubectl get pv task-pv-volume
|
||
|
||
<!--
|
||
The output shows that the PersistentVolume has a `STATUS` of `Available`. This
|
||
means it has not yet been bound to a PersistentVolumeClaim.
|
||
-->
|
||
|
||
输出结果显示该 PersistentVolume 的`状态（STATUS）` 为 `Available`。
|
||
这意味着它还没有被绑定给 PersistentVolumeClaim。
|
||
|
||
NAME CAPACITY ACCESSMODES RECLAIMPOLICY STATUS CLAIM STORAGECLASS REASON AGE
|
||
task-pv-volume 10Gi RWO Retain Available manual 4s
|
||
|
||
<!--
|
||
## Create a PersistentVolumeClaim
|
||
|
||
The next step is to create a PersistentVolumeClaim. Pods use PersistentVolumeClaims
|
||
to request physical storage. In this exercise, you create a PersistentVolumeClaim
|
||
that requests a volume of at least three gibibytes that can provide read-write
|
||
access for at least one Node.
|
||
|
||
Here is the configuration file for the PersistentVolumeClaim:
|
||
-->
|
||
|
||
## 创建 PersistentVolumeClaim
|
||
|
||
下一步是创建一个 PersistentVolumeClaim。
|
||
Pod 使用 PersistentVolumeClaim 来请求物理存储。
|
||
在本练习中，您将创建一个 PersistentVolumeClaim，它请求至少 3 吉比特容量的卷，该卷至少可以为一个节点提供读写访问。
|
||
|
||
下面是 PersistentVolumeClaim 的配置文件：
|
||
|
||
{{< codenew file="pods/storage/pv-claim.yaml" >}}
|
||
|
||
<!--
|
||
Create the PersistentVolumeClaim:
|
||
-->
|
||
|
||
创建 PersistentVolumeClaim：
|
||
|
||
kubectl create -f https://k8s.io/examples/pods/storage/pv-claim.yaml
|
||
|
||
<!--
|
||
After you create the PersistentVolumeClaim, the Kubernetes control plane looks
|
||
for a PersistentVolume that satisfies the claim's requirements. If the control
|
||
plane finds a suitable PersistentVolume with the same StorageClass, it binds the
|
||
claim to the volume.
|
||
|
||
Look again at the PersistentVolume:
|
||
-->
|
||
|
||
创建 PersistentVolumeClaim 之后，Kubernetes 控制平面将查找满足申领要求的 PersistentVolume。
|
||
如果控制平面找到具有相同 StorageClass 的适当的 PersistentVolume，则将 PersistentVolumeClaim 绑定到该 PersistentVolume 上。
|
||
|
||
再次查看 PersistentVolume 信息：
|
||
|
||
kubectl get pv task-pv-volume
|
||
|
||
<!--
|
||
Now the output shows a `STATUS` of `Bound`.
|
||
-->
|
||
现在输出的 `STATUS` 为 `Bound`。
|
||
|
||
NAME CAPACITY ACCESSMODES RECLAIMPOLICY STATUS CLAIM STORAGECLASS REASON AGE
|
||
task-pv-volume 10Gi RWO Retain Bound default/task-pv-claim manual 2m
|
||
|
||
<!--
|
||
Look at the PersistentVolumeClaim:
|
||
-->
|
||
查看 PersistentVolumeClaim：
|
||
|
||
kubectl get pvc task-pv-claim
|
||
|
||
<!--
|
||
The output shows that the PersistentVolumeClaim is bound to your PersistentVolume,
|
||
`task-pv-volume`.
|
||
-->
|
||
|
||
输出结果表明该 PersistentVolumeClaim 绑定了你的 PersistentVolume `task-pv-volume`。
|
||
|
||
NAME STATUS VOLUME CAPACITY ACCESSMODES STORAGECLASS AGE
|
||
task-pv-claim Bound task-pv-volume 10Gi RWO manual 30s
|
||
|
||
<!--
|
||
## Create a Pod
|
||
|
||
The next step is to create a Pod that uses your PersistentVolumeClaim as a volume.
|
||
|
||
Here is the configuration file for the Pod:
|
||
-->
|
||
|
||
## 创建 Pod
|
||
|
||
下一步是创建一个 Pod， 该 Pod 使用你的 PersistentVolumeClaim 作为存储卷。
|
||
|
||
下面是 Pod 的 配置文件：
|
||
|
||
{{< codenew file="pods/storage/pv-pod.yaml" >}}
|
||
|
||
<!--
|
||
Notice that the Pod's configuration file specifies a PersistentVolumeClaim, but
|
||
it does not specify a PersistentVolume. From the Pod's point of view, the claim
|
||
is a volume.
|
||
|
||
Create the Pod:
|
||
-->
|
||
|
||
注意 Pod 的配置文件指定了 PersistentVolumeClaim，但没有指定 PersistentVolume。对 Pod 而言，PersistentVolumeClaim 就是一个存储卷。
|
||
|
||
创建 Pod：
|
||
|
||
kubectl create -f https://k8s.io/examples/pods/storage/pv-pod.yaml
|
||
|
||
<!--
|
||
Verify that the Container in the Pod is running;
|
||
-->
|
||
|
||
检查 Pod 中的容器是否运行正常：
|
||
|
||
kubectl get pod task-pv-pod
|
||
|
||
<!--
|
||
Get a shell to the Container running in your Pod:
|
||
-->
|
||
|
||
打开一个 shell 访问 Pod 中的容器：
|
||
|
||
kubectl exec -it task-pv-pod -- /bin/bash
|
||
|
||
<!--
|
||
In your shell, verify that nginx is serving the `index.html` file from the
|
||
hostPath volume:
|
||
-->
|
||
|
||
在 shell 中，验证 nginx 是否正在从 hostPath 卷提供 `index.html` 文件：
|
||
|
||
root@task-pv-pod:/# apt-get update
|
||
root@task-pv-pod:/# apt-get install curl
|
||
root@task-pv-pod:/# curl localhost
|
||
|
||
<!--
|
||
The output shows the text that you wrote to the `index.html` file on the
|
||
hostPath volume:
|
||
-->
|
||
|
||
输出结果是你之前写到 hostPath 卷中的 `index.html` 文件中的内容：
|
||
|
||
Hello from Kubernetes storage
|
||
|
||
{{% /capture %}}
|
||
|
||
|
||
{{% capture discussion %}}
|
||
|
||
<!--
|
||
## Access control
|
||
|
||
Storage configured with a group ID (GID) allows writing only by Pods using the same
|
||
GID. Mismatched or missing GIDs cause permission denied errors. To reduce the
|
||
need for coordination with users, an administrator can annotate a PersistentVolume
|
||
with a GID. Then the GID is automatically added to any Pod that uses the
|
||
PersistentVolume.
|
||
|
||
Use the `pv.beta.kubernetes.io/gid` annotation as follows:
|
||
-->
|
||
|
||
## 访问控制
|
||
|
||
使用 group ID（GID）配置的存储仅允许 Pod 使用相同的 GID 进行写入。
|
||
GID 不匹配或缺少将会导致许可被拒绝的错误。
|
||
为了减少与用户的协调，管理员可以使用 GID 对 PersistentVolume 进行注解。
|
||
这样 GID 就能自动的添加到使用 PersistentVolume 的任何 Pod 中。
|
||
|
||
使用 `pv.beta.kubernetes.io/gid` 注解的方法如下所示：
|
||
|
||
```yaml
|
||
kind: PersistentVolume
|
||
apiVersion: v1
|
||
metadata:
|
||
name: pv1
|
||
annotations:
|
||
pv.beta.kubernetes.io/gid: "1234"
|
||
```
|
||
|
||
<!--
|
||
When a Pod consumes a PersistentVolume that has a GID annotation, the annotated GID
|
||
is applied to all Containers in the Pod in the same way that GIDs specified in the
|
||
Pod’s security context are. Every GID, whether it originates from a PersistentVolume
|
||
annotation or the Pod’s specification, is applied to the first process run in
|
||
each Container.
|
||
-->
|
||
|
||
当 Pod 使用带有 GID 注解的 PersistentVolume 时，注解的 GID 会被应用于 Pod 中的所有容器，应用的方法与 Pod 的安全上下文中指定的 GID 相同。
|
||
每个 GID，无论是来自 PersistentVolume 注解还是来自 Pod 的规范，都应用于每个容器中运行的第一个进程。
|
||
|
||
{{< note >}}
|
||
<!--
|
||
When a Pod consumes a PersistentVolume, the GIDs associated with the
|
||
PersistentVolume are not present on the Pod resource itself.
|
||
-->
|
||
当 Pod 使用 PersistentVolume 时，与 PersistentVolume 关联的 GID 不会在 Pod 本身的资源对象上出现。
|
||
{{< /note >}}
|
||
|
||
{{% /capture %}}
|
||
|
||
|
||
{{% capture whatsnext %}}
|
||
|
||
<!--
|
||
* Learn more about [PersistentVolumes](/docs/concepts/storage/persistent-volumes/).
|
||
* Read the [Persistent Storage design document](https://git.k8s.io/community/contributors/design-proposals/storage/persistent-storage.md).
|
||
-->
|
||
|
||
* 进一步了解 [PersistentVolumes](/docs/concepts/storage/persistent-volumes/)。
|
||
* 阅读[持久存储设计文档](https://git.k8s.io/community/contributors/design-proposals/storage/persistent-storage.md)。
|
||
|
||
<!--
|
||
### Reference
|
||
-->
|
||
|
||
### 参考
|
||
|
||
* [PersistentVolume](/docs/reference/generated/kubernetes-api/{{< param "version" >}}/#persistentvolume-v1-core)
|
||
* [PersistentVolumeSpec](/docs/reference/generated/kubernetes-api/{{< param "version" >}}/#persistentvolumespec-v1-core)
|
||
* [PersistentVolumeClaim](/docs/reference/generated/kubernetes-api/{{< param "version" >}}/#persistentvolumeclaim-v1-core)
|
||
* [PersistentVolumeClaimSpec](/docs/reference/generated/kubernetes-api/{{< param "version" >}}/#persistentvolumeclaimspec-v1-core)
|
||
|
||
|
||
{{% /capture %}}
|