Vanitas笔记

kubernetes学习笔记(storage)

  • 2021-06-23
  • 作者 Vanitas
  • ~5.91K 字
  1. 1. 存储相关概念
  2. 2. 环境准备
  3. 3. pv相关属性：
    1. 3.1. pv的状态
  4. 4. pv实践
  5. 5. 使用pvc作为服务的存储
  6. 6. StorageClass实践

存储相关概念

pv： 持久化卷，可以使用ceph和nfs等
pvc: 持久化卷声明,用于调度pv资源
StorageClass： 定义存储类型，动态分配存储资源

环境准备

首先建立一个nfs的server，此处不做多讲，kubernetes节点上也安装nfs服务

1
2
systemctl enable --now rpcbind
systemctl enable --now nfs

pv相关属性：

pv相关属性包括了Capacity(存储能力)、AccessModes(访问模式)、ReclaimPolicy(回收策略)。

基本的capacity指标为storage=”存储容量”。
访问模式包含以下三种：
ReadWriteOnce（RWO）：读写权限，但是只能被单个节点挂载

ReadOnlyMany（ROX）：只读权限，可以被多个节点挂载

ReadWriteMany（RWX）：读写权限，可以被多个节点挂载

注: 不同的存储方式支持的访问模式不同，请参阅相关指南。
回收策略：

Retain（保留）- 保留数据，需要管理员手工清理数据

Recycle（回收）- 清除 PV 中的数据，效果相当于执行 rm -rf /yourdir/*

Delete（删除）- 与 PV 相连的后端存储完成 volume 的删除操作

pv的状态

通常有以下几种：
Available（可用）：表示可用状态，还未被任何 PVC 绑定

Bound（已绑定）：表示 PV 已经被 PVC 绑定

Released（已释放）：PVC 被删除，但是资源还未被集群重新声明

Failed（失败）： 表示该 PV 的自动回收失败

pv实践

接下来新建pv对象(pv1.yaml)：

1
2
3
4
5
6
7
8
9
10
11
12
13
apiVersion: v1
kind: PersistentVolume
metadata:
  name:  pv1
spec:
  capacity:
    storage: 1Gi
  accessModes:
  - ReadWriteOnce
  persistentVolumeReclaimPolicy: Recycle
  nfs:
    path: /data/k8s
    server: 192.168.1.42 #此处填你的nfs服务器地址

应用:

1
2
kubectl create -f pv1.yaml
persistentvolume "pv1" created

创建pvc

1
2
3
4
5
6
7
8
9
10
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: pvc-nfs
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 1Gi

注: pvc会自动寻找available状态的pv，无需额外声明。如果pv为2Gi，pvc为1Gi，同样会进行绑定，且pvc的容量会变成2Gi。

使用pvc作为服务的存储

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment
spec:
  selector:
    matchLabels:
      app: nginx
  replicas: 2
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:1.7.9
        ports:
        - containerPort: 80
          name: web
        volumeMounts:
        - name: www
          subPath: nginx-test
          mountPath: /usr/share/nginx/html
      volumes:
      - name: www
        persistentVolumeClaim:
          claimName: pvc2-nfs

nginx-service.yaml

1
2
3
4
5
6
7
8
9
10
11
12
13
apiVersion: v1
kind: Service
metadata:
  name: nginx
  labels:
    app: nginx
spec:
  type: NodePort
  ports:
  - port: 80
    targetPort: web
  selector:
    app: nginx

nginx-ingress.ymal

1
2
3
4
5
6
7
8
9
10
11
12
13
apiVersion: traefik.containo.us/v1alpha1
kind: IngressRoute
metadata:
  name: nginx-route
spec:
  entryPoints:
  - web
  routes:
  - match: Host(`nginx.k8s.local`)
    kind: Rule
    services:
      - name: nginx
        port: 80

StorageClass实践

新建nfs-client的deployment

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
apiVersion: apps/v1 
kind: Deployment
metadata:
  name: nfs-client-provisioner
spec:
  replicas: 1
  strategy:
    type: Recreate
  selector:
    matchLabels:
      app: nfs-client-provisioner
  template:
    metadata:
      labels:
        app: nfs-client-provisioner
    spec:
      serviceAccountName: nfs-client-provisioner
      containers:
        - name: nfs-client-provisioner
          image: quay.io/external_storage/nfs-client-provisioner:latest
          volumeMounts:
            - name: nfs-client-root
              mountPath: /persistentvolumes
          env:
            - name: PROVISIONER_NAME
              value: fuseim.pri/ifs
            - name: NFS_SERVER
              value: 192.168.1.42 #nfs服务器地址
            - name: NFS_PATH
              value: /data/k8s #nfs共享存储路径
      volumes:
        - name: nfs-client-root
          nfs:
            server: 192.168.1.42 # nfs服务器地址
            path: /data/k8s #nfs共享存储路径

创建nfs-client的serviceaccount：

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
apiVersion: v1
kind: ServiceAccount
metadata:
  name: nfs-client-provisioner

---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: nfs-client-provisioner-runner
rules:
  - apiGroups: [""]
    resources: ["persistentvolumes"]
    verbs: ["get", "list", "watch", "create", "delete"]
  - apiGroups: [""]
    resources: ["persistentvolumeclaims"]
    verbs: ["get", "list", "watch", "update"]
  - apiGroups: ["storage.k8s.io"]
    resources: ["storageclasses"]
    verbs: ["get", "list", "watch"]
  - apiGroups: [""]
    resources: ["events"]
    verbs: ["list", "watch", "create", "update", "patch"]
  - apiGroups: [""]
    resources: ["endpoints"]
    verbs: ["create", "delete", "get", "list", "watch", "patch", "update"]

---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: run-nfs-client-provisioner
subjects:
  - kind: ServiceAccount
    name: nfs-client-provisioner
    namespace: default
roleRef:
  kind: ClusterRole
  name: nfs-client-provisioner-runner
  apiGroup: rbac.authorization.k8s.io

此处新建了一个serviceaccount同时绑定了一个clusterrole（用于声明权限）

创建sc对象

1
2
3
4
5
6
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
  name: nfs-storage
provisioner: fuseim.pri/ifs # 此处名字与deployment中的PROVISIONER_NAME对应

1
2
3
kubectl create -f nfs-client.yaml
kubectl create -f nfs-client-sa.yaml
kubectl create -f nfs-client-class.yaml

使用StorageClass 创建服务

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: nfs-web
spec:
  serviceName: "nginx"
  replicas: 3
  selector:
    matchLabels:
      app: nfs-web
  template:
    metadata:
      labels:
        app: nfs-web
    spec:
      terminationGracePeriodSeconds: 10
      containers:
      - name: nginx
        image: nginx:1.7.9
        ports:
        - containerPort: 80
          name: web
        volumeMounts:
        - name: www
          mountPath: /usr/share/nginx/html
  volumeClaimTemplates:
  - metadata:
      name: www
      annotations:
        volume.beta.kubernetes.io/storage-class: nfs-storage
    spec:
      accessModes: [ "ReadWriteOnce" ]
      resources:
        requests:
          storage: 1Gi
1
kubectl create -f statefulset-nfs.yaml
本作品采用 知识共享署名-相同方式共享 4.0 国际许可协议 进行许可
, , ,
最后编辑：2021-06-28