一、概念

PV（Persistent Volume）和PVC（Persistent Volume Claim）是Kubernetes中用于管理存储资源的两个核心概念，它们通过解耦存储资源与应用需求实现灵活管理。以下是两者的核心区别及协作机制：

PV‌ 是集群管理员预先配置的‌物理存储资源‌，如NFS、云存储或本地磁盘等，其生命周期独立于Pod存在‌。

‌PVC‌ 是用户为应用程序提交的‌存储需求申请‌，通过声明容量、访问模式等参数匹配可用PV‌

• 管理员创建PV或定义存储模板（如StorageClass）‌

• 用户提交PVC申请，Kubernetes自动匹配符合条件的PV‌

• 若动态供给已启用，未匹配的PVC可触发自动创建新PV‌

二、静态供给

在Kubernetes中，‌静态供给（Static Provisioning）‌是指管理员预先创建并配置好PV（PersistentVolume），然后由用户通过PVC（PersistentVolumeClaim）申请匹配的存储资源。

yml
# ========== PersistentVolume (PV) 定义 ==========
apiVersion: v1
kind: PersistentVolume
metadata:
  name: static-pv-nfs
spec:
  capacity:
    storage: 1Gi  # PV的总容量
  accessModes:
    - ReadWriteMany  # 支持多节点同时读写
  persistentVolumeReclaimPolicy: Retain  # Pod删除后保留PV和数据
  nfs:
    server: 192.168.201.104  # NFS服务器地址
    path: "/data/nfs_share"  # NFS服务器共享路径
    # 可选参数：readOnly: false  # 默认可读写

---
# ========== PersistentVolumeClaim (PVC) 定义 ==========
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: static-pvc-app  # PVC名称，Pod中会引用此名称
spec:
  accessModes:
    - ReadWriteMany  # 必须与PV的accessModes匹配
  resources:
    requests:
      storage: 1Gi  # 申请1GB存储空间，申请的容量必须和PV一样
  storageClassName: ""  # 显式设置为空字符串以确保使用静态供给

---
# ========== Pod 定义 ==========
apiVersion: v1
kind: Pod
metadata:
  name: nginx-with-pvc  # Pod名称
spec:
  containers:
  - name: nginx
    image: nginx:latest
    volumeMounts:
    - name: nfs-storage  # 必须与volumes.name匹配
      mountPath: "/usr/share/nginx/html"  # 容器内挂载路径
      # 可选参数：readOnly: false  # 默认可读写
  volumes:
  - name: nfs-storage  # 卷名称
    persistentVolumeClaim:
      claimName: static-pvc-app  # 绑定前面定义的PVC
      # 可选参数：readOnly: false  # 默认可读写

三、动态供给

Kubernetes中PV（PersistentVolume）和PVC（PersistentVolumeClaim）的动态供给是一种自动化存储资源分配机制。

动态供给‌：当用户创建PVC时，系统根据预定义的StorageClass自动创建并绑定匹配的PV，无需管理员手动预置PV。

yml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: nfs-client-provisioner
  labels:
    app: nfs-client-provisioner
  # replace with namespace where provisioner is deployed
  namespace: kube-system
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: chronolaw/nfs-subdir-external-provisioner:v4.0.2
          volumeMounts:
            - name: nfs-client-root
              mountPath: /persistentvolumes
          env:
            - name: PROVISIONER_NAME
              value: k8s-sigs.io/nfs-subdir-external-provisioner
            - name: NFS_SERVER
              value: 192.168.201.104  #nfs服务器ip地址
            - name: NFS_PATH
              value: /root/nfs/data  #nfs服务器共享数据目录
      volumes:
        - name: nfs-client-root
          nfs:
            server: 192.168.201.104    #nfs服务器ip地址
            path: /root/nfs/data      #nfs服务器共享数据目录

yml
apiVersion: v1
kind: ServiceAccount
metadata:
  name: nfs-client-provisioner
  # replace with namespace where provisioner is deployed
  namespace: kube-system
---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: nfs-client-provisioner-runner
rules:
  - apiGroups: [""]
    resources: ["nodes"]
    verbs: ["get", "list", "watch"]
  - 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: ["create", "update", "patch"]
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: run-nfs-client-provisioner
subjects:
  - kind: ServiceAccount
    name: nfs-client-provisioner
    # replace with namespace where provisioner is deployed
    namespace: kube-system
roleRef:
  kind: ClusterRole
  name: nfs-client-provisioner-runner
  apiGroup: rbac.authorization.k8s.io
---
kind: Role
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: leader-locking-nfs-client-provisioner
  # replace with namespace where provisioner is deployed
  namespace: kube-system
rules:
  - apiGroups: [""]
    resources: ["endpoints"]
    verbs: ["get", "list", "watch", "create", "update", "patch"]
---
kind: RoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: leader-locking-nfs-client-provisioner
  # replace with namespace where provisioner is deployed
  namespace: kube-system
subjects:
  - kind: ServiceAccount
    name: nfs-client-provisioner
    # replace with namespace where provisioner is deployed
    namespace: kube-system
roleRef:
  kind: Role
  name: leader-locking-nfs-client-provisioner
  apiGroup: rbac.authorization.k8s.io

yml
# ==================== 存储类配置 ====================
apiVersion: storage.k8s.io/v1    # 存储类API版本标识
kind: StorageClass               # 声明资源类型为存储类
metadata:                        # 资源元数据开始
  name: mysql-nfs-sc             # 存储类命名（MySQL专用NFS存储类）
  namespace: ems                 # 归属ems命名空间
provisioner: k8s-sigs.io/nfs-subdir-external-provisioner  # 指定NFS子目录动态供应器
parameters:                      # 供应器参数配置开始
  onDelete: "remain"             # 数据保留策略：删除时不清理

yml
# ==================== 命名空间配置 ====================
apiVersion: v1                   # Kubernetes核心API版本标识
kind: Namespace                  # 声明资源类型为命名空间
metadata:                        # 资源元数据开始
  name: ems                      # 定义命名空间名称为ems（Enterprise Management System）
---

# ==================== 有状态应用配置 ====================
apiVersion: apps/v1              # 应用API版本标识
kind: StatefulSet                # 声明资源类型为有状态副本集
metadata:                        # 资源元数据开始
  name: mysql                    # StatefulSet名称
  namespace: ems                 # 归属ems命名空间
  labels:                        # 标签集合开始
    app: mysql                   # 应用标识标签
spec:                            # 规格定义开始
  serviceName: mysql-headless    # 关联的无头服务名（用于DNS解析）
  replicas: 1                    # 副本数配置（MySQL单实例部署）

  template:                      # Pod模板定义开始
    metadata:                    # Pod元数据开始
      labels:                    # Pod标签集合开始
        app: mysql               # 应用标识标签（需与selector匹配）
    spec:                        # Pod规格定义开始
      containers:                # 容器定义列表开始
      - name: mysql              # 容器名称标识
        image: mysql/mysql-server:8.0  # 官方MySQL 8.0镜像
        ports:                   # 端口映射列表开始
        - containerPort: 3306    # MySQL服务默认端口
        env:                     # 环境变量列表开始
        - name: MYSQL_ROOT_PASSWORD  # root密码变量名
          value: "root"          # 密码明文值（测试环境使用）
        volumeMounts:            # 存储卷挂载列表开始
        - name: data             # 引用下方PVC模板名称
          mountPath: /var/lib/mysql  # MySQL数据存储路径

  volumeClaimTemplates:          # PVC模板列表开始
  - metadata:                    # PVC元数据开始
      name: data                 # PVC资源名称
    spec:                        # PVC规格定义开始
      accessModes: [ "ReadWriteMany" ]  # 存储访问模式（多节点读写）
      storageClassName: "mysql-nfs-sc"  # 绑定前文定义的存储类
      resources:                 # 资源请求定义开始
        requests:                # 资源请求参数开始
          storage: 2Gi           # 存储空间大小请求值

  selector:                      # Pod选择器定义开始
    matchLabels:                 # 标签匹配规则开始
      app: mysql                 # 需匹配的Pod标签键值