持久卷 #

PV和PVC关系
    │
    ├── PV (PersistentVolume)
    │   └── 集群级存储资源
    │
    ├── PVC (PersistentVolumeClaim)
    │   └── 命名空间级存储请求
    │
    └── 绑定关系
        └── PVC绑定到满足条件的PV

存储生命周期
    │
    ├── Provisioning（供给）
    │   ├── 静态供给
    │   └── 动态供给
    │
    ├── Binding（绑定）
    │   └── PVC绑定PV
    │
    ├── Using（使用）
    │   └── Pod通过PVC使用存储
    │
    └── Reclaiming（回收）
        ├── Retain（保留）
        ├── Delete（删除）
        └── Recycle（回收，已废弃）

apiVersion: v1
kind: PersistentVolume
metadata:
  name: pv-nfs
spec:
  capacity:
    storage: 5Gi
  volumeMode: Filesystem
  accessModes:
  - ReadWriteOnce
  - ReadOnlyMany
  persistentVolumeReclaimPolicy: Retain
  storageClassName: nfs
  nfs:
    server: 192.168.1.100
    path: /data/pv1

# NFS PV
apiVersion: v1
kind: PersistentVolume
metadata:
  name: pv-nfs
spec:
  capacity:
    storage: 5Gi
  accessModes:
  - ReadWriteMany
  nfs:
    server: 192.168.1.100
    path: /data/pv
---
# HostPath PV
apiVersion: v1
kind: PersistentVolume
metadata:
  name: pv-hostpath
spec:
  capacity:
    storage: 10Gi
  accessModes:
  - ReadWriteOnce
  hostPath:
    path: /data/pv
    type: DirectoryOrCreate
---
# iSCSI PV
apiVersion: v1
kind: PersistentVolume
metadata:
  name: pv-iscsi
spec:
  capacity:
    storage: 20Gi
  accessModes:
  - ReadWriteOnce
  iscsi:
    targetPortal: 192.168.1.200:3260
    iqn: iqn.2001-04.com.example:storage.target00
    lun: 0
    fsType: ext4

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: pvc-demo
spec:
  accessModes:
  - ReadWriteOnce
  resources:
    requests:
      storage: 5Gi
  storageClassName: nfs

# 创建PVC
kubectl apply -f pvc.yaml

# 查看PVC
kubectl get pvc

# 输出示例
NAME        STATUS   VOLUME   CAPACITY   ACCESS MODES   STORAGECLASS   AGE
pvc-demo    Bound    pv-nfs   5Gi        RWO            nfs            10s

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: pvc-selector
spec:
  accessModes:
  - ReadWriteOnce
  resources:
    requests:
      storage: 5Gi
  selector:
    matchLabels:
      environment: production
    matchExpressions:
    - key: tier
      operator: In
      values:
      - database

apiVersion: v1
kind: Pod
metadata:
  name: pvc-pod
spec:
  containers:
  - name: nginx
    image: nginx
    volumeMounts:
    - name: data
      mountPath: /usr/share/nginx/html
  volumes:
  - name: data
    persistentVolumeClaim:
      claimName: pvc-demo

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment
spec:
  replicas: 1
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx
        volumeMounts:
        - name: data
          mountPath: /usr/share/nginx/html
      volumes:
      - name: data
        persistentVolumeClaim:
          claimName: pvc-demo

apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: web
spec:
  serviceName: web
  replicas: 3
  selector:
    matchLabels:
      app: web
  template:
    metadata:
      labels:
        app: web
    spec:
      containers:
      - name: nginx
        image: nginx
        volumeMounts:
        - name: www
          mountPath: /usr/share/nginx/html
  volumeClaimTemplates:
  - metadata:
      name: www
    spec:
      accessModes:
      - ReadWriteOnce
      resources:
        requests:
          storage: 1Gi

PVC绑定过程
    │
    ├── 1. 用户创建PVC
    │
    ├── 2. 控制器查找匹配的PV
    │   ├── 容量满足
    │   ├── 访问模式匹配
    │   └── StorageClass匹配
    │
    ├── 3. 绑定PV到PVC
    │
    └── 4. 更新PV和PVC状态

# 查看PV列表
kubectl get pv

# 查看PV详情
kubectl describe pv <pv-name>

# 查看PV YAML
kubectl get pv <pv-name> -o yaml

# 查看PVC列表
kubectl get pvc

# 查看PVC详情
kubectl describe pvc <pvc-name>

# 查看特定命名空间
kubectl get pvc -n <namespace>

# 删除PVC
kubectl delete pvc <pvc-name>

# 删除后PV状态变为Released
# 根据回收策略处理数据

# PV定义
apiVersion: v1
kind: PersistentVolume
metadata:
  name: pv-web
  labels:
    app: web
    environment: production
spec:
  capacity:
    storage: 10Gi
  volumeMode: Filesystem
  accessModes:
  - ReadWriteOnce
  persistentVolumeReclaimPolicy: Retain
  storageClassName: manual
  nfs:
    server: 192.168.1.100
    path: /data/web
---
# PVC定义
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: pvc-web
spec:
  accessModes:
  - ReadWriteOnce
  resources:
    requests:
      storage: 10Gi
  storageClassName: manual
  selector:
    matchLabels:
      app: web
---
# Pod使用PVC
apiVersion: v1
kind: Pod
metadata:
  name: web-pod
spec:
  containers:
  - name: nginx
    image: nginx
    volumeMounts:
    - name: data
      mountPath: /usr/share/nginx/html
  volumes:
  - name: data
    persistentVolumeClaim:
      claimName: pvc-web

# 查看PVC状态
kubectl describe pvc <pvc-name>

# 查看PV状态
kubectl describe pv <pv-name>

# 查看事件
kubectl get events --field-selector involvedObject.name=<pvc-name>

命名建议
    │
    ├── PV命名：pv-<storage-type>-<purpose>
    │   └── 示例：pv-nfs-web
    │
    └── PVC命名：pvc-<app-name>-<purpose>
        └── 示例：pvc-nginx-data

# 合理设置容量
resources:
  requests:
    storage: 10Gi

# PV容量略大于PVC请求
capacity:
  storage: 12Gi

# 只读挂载
volumeMounts:
- name: data
  mountPath: /data
  readOnly: true