副本之间的 kubernetes 部署的共享目录

Question

我有一个包含 2 个副本的简单部署。

我希望每个副本都有相同的存储文件夹（共享应用程序上传文件夹）

我一直在研究索赔和数量，但仍然没有优势，所以寻求快速帮助/示例。

apiVersion: apps/v1
    kind: Deployment
    metadata:
      name: 'test-tomcat'
      labels:
        app: test-tomcat
    spec:
      selector:
        matchLabels:
          app: test-tomcat
      replicas: 3
      template:
        metadata:
          name: 'test-tomcat'
          labels:
            app: test-tomcat
        spec:
          volumes:
          - name: 'data'
            persistentVolumeClaim:
              claimName: claim
          containers:
          - image: 'tomcat:9-alpine'
            volumeMounts:
            - name: 'data'
              mountPath: '/app/data'
            imagePullPolicy: Always
            name: 'tomcat'
            command: ['bin/catalina.sh', 'jpda', 'run']

kind: PersistentVolume
apiVersion: v1
metadata:
  name: volume
  labels:
    type: local
spec:
  storageClassName: manual
  capacity:
    storage: 2Gi
  accessModes:
  - ReadWriteMany
  hostPath:
    path: "/mnt/data"

kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: claim
spec:
  storageClassName: manual
  accessModes:
  - ReadWriteMany
  resources:
    requests:
      storage: 1Gi

Answer 1

首先，您需要决定使用什么类型的持久卷。以下是本地集群的几个示例：

HostPath - 节点上的本地路径。因此，如果第一个 Pod 位于 Node1 上，第二个 Pod 位于 Node2 上，则存储将不同。要解决此问题，您可以使用以下选项之一。主机路径示例：

kind: PersistentVolume
apiVersion: v1
metadata:
  name: example-pv
  labels:
    type: local
spec:
  storageClassName: manual
  capacity:
    storage: 3Gi
  accessModes:
    - ReadWriteOnce
  hostPath:
    path: "/mnt/data"

NFS - 该类型的 PersistentVolume 使用网络文件系统。 NFS 是一种分布式文件系统协议，允许您在服务器上挂载远程目录。在 Kubernetes 中使用 NFS 之前需要先安装 NFS 服务器；这是示例 How To Set Up an NFS Mount on Ubuntu。 Kubernetes 中的示例：

apiVersion: v1
kind: PersistentVolume
metadata:
  name: example-pv
spec:
  capacity:
    storage: 3Gi
  volumeMode: Filesystem
  accessModes:
    - ReadWriteOnce
  persistentVolumeReclaimPolicy: Recycle
  storageClassName: slow
  mountOptions:
    - hard
    - nfsvers=4.1
  nfs:
    path: /tmp
    server: 172.17.0.2

GlusterFS - GlusterFS 是一个可扩展的分布式文件系统，它将来自多个服务器的磁盘存储资源聚合到一个全局命名空间中。至于NFS，在Kubernetes中使用之前需要先安装GlusterFS；这是 link with instructions, and one 更多示例。 Kubernetes 中的示例：

apiVersion: v1
kind: PersistentVolume
metadata:
  name: example-pv 
  annotations:
    pv.beta.kubernetes.io/gid: "590" 
spec:
  capacity:
    storage: 3Gi 
  accessModes: 
    - ReadWriteMany
  glusterfs:
    endpoints: glusterfs-cluster 
    path: myVol1 
    readOnly: false
  persistentVolumeReclaimPolicy: Retain
---
apiVersion: v1
kind: Service
metadata:
  name: glusterfs-cluster 
spec:
  ports:
  - port: 1
---
apiVersion: v1
kind: Endpoints
metadata:
  name: glusterfs-cluster 
subsets:
  - addresses:
      - ip: 192.168.122.221 
    ports:
      - port: 1 
  - addresses:
      - ip: 192.168.122.222 
    ports:
      - port: 1 
  - addresses:
      - ip: 192.168.122.223 
    ports:
      - port: 1

创建PersistentVolume后，需要创建一个PersistaentVolumeClaim。 PersistaentVolumeClaim 是 Pods 用于从存储请求卷的资源。创建 PersistentVolumeClaim 后，Kubernetes 控制平面会查找满足声明要求的 PersistentVolume。示例：

kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: example-pv-claim
spec:
  storageClassName: manual
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 3Gi

最后一步，您需要配置 Pod 以使用 PersistentVolumeClaim。这是示例：

apiVersion: apps/v1
kind: Deployment
metadata:
  name: 'test-tomcat'
  labels:
    app: test-tomcat
spec:
  selector:
    matchLabels:
      app: test-tomcat
  replicas: 3
  template:
    metadata:
      name: 'test-tomcat'
      labels:
        app: test-tomcat
    spec:
      volumes:
      - name: 'data'
        persistentVolumeClaim:
          claimName: example-pv-claim #name of the claim should be the same as defined before
      containers:
      - image: 'tomcat:9-alpine'
        volumeMounts:
        - name: 'data'
          mountPath: '/app/data'
        imagePullPolicy: Always
        name: 'tomcat'
        command: ['bin/catalina.sh', 'jpda', 'run']

副本之间的 kubernetes 部署的共享目录

Shared directory for a kubernetes Deployment between it's replicas

kubernetes

persistent-volumes

persistent-volume-claims