Kubernetes-PV/PVC

PV (Persistent Volume)

和Volume的区别

• 只能是网络存储
• 独立于Pod之外

PV支持的主流存储方案：

• GCEPersistentDisk
• AWSElasticBlockStore
• AzureFile
• AzureDisk
• FC (Fibre Channel)
• Flocker
• NFS
• iSCSI
• RBD (Ceph Block Device)
• CephFS
• Cinder (OpenStack block storage)
• Glusterfs
• VsphereVolume
• Quobyte Volumes
• HostPath (single node testing only – local storage is not supported in any way and WILL NOT WORK in a multi-node cluster)
• VMware Photon

创建PV

apiVersion: v1
kind: PersistentVolume
metadata:
  name: pv001
spec:
  capacity:
    storage: 10Gi
  accessModes:
    - ReadWriteMany
  persistentVolumeReclaimPolicy: Recycle 
  nfs:
    path: /data/k8s/
    server: 172.16.1.131

accessModes

• ReadWriteOnce – PV以 read-write 挂载到一个节点
• ReadOnlyMany – PV以read-only方式挂载到多个节点
• ReadWriteMany – PV以read-write方式挂载到多个节点

Reclaim

当前支持的回收策略:

• Retain – 允许用户手动回收
• Recycle – 删除PV上的数据 (“rm -rf /thevolume/*”)
• Delete – 删除PV

Phase

• Available – PV可以被使用
• Bound – PV被绑定到PVC
• Released – 被绑定的PVC被删除，可以被Reclaim
• Failed – 自动回收失败

PVC (Persistent Volume Claim)

创建PVC

kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: myclaim
spec:
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 8Gi

Phase

Pending – 等待可用的PV
Bound – PV被绑定到PVC
Lost – 找不到绑定的PV

在Pod中使用

kind: Pod
apiVersion: v1
metadata:
name: mypod
spec:
containers:
- name: myfrontend
  image: dockerfile/nginx
  volumeMounts:
  - mountPath: "/var/www/html"
    name: mypd
volumes:
- name: mypd
  persistentVolumeClaim:
    claimName: myclaim