K8S當中的本地卷(Local PV)的使用

Local PV是從kuberntes 1.10開始引入，本質目的是爲了解決hostPath的缺陷。經過PV控制器與Scheduler的結合，會對local PV作針對性的邏輯處理，從而，讓Pod在屢次調度時，可以調度到同一個Node上。

此次，測試了一下將local PV掛載到一個httpd的應用上。

要注意，pvc是按namespace提供的。還有，matchExpressions做匹配的主機名規則。

一，local-pv.yaml

kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
  name: local-storage
provisioner: kubernetes.io/no-provisioner
volumeBindingMode: WaitForFirstConsumer
---
apiVersion: v1
kind: PersistentVolume
metadata:
  name: local-pv-sda
spec:
  capacity:
    storage: 100Gi
  accessModes:
  - ReadWriteOnce
  persistentVolumeReclaimPolicy: Retain
  storageClassName: local-storage
  local: path: /data/pv
  nodeAffinity:
    required:
      nodeSelectorTerms:
      - matchExpressions:
        - key: kubernetes.io/hostname
          operator: In
          values:
          - spark-docker
---
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: local-pvc-sda
  namespace: in-demo
spec:
  accessModes:
  - ReadWriteOnce
  storageClassName: local-storage
  resources:
    requests:
      storage: 10Gi

 

二，httpd.yaml

apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: httpd
  namespace: in-demo
spec:
  replicas: 2
  revisionHistoryLimit: 5
  strategy:
    type: RollingUpdate
    rollingUpdate:
      maxSurge: 1
      maxUnavailable: 0
  template:
    metadata:
      labels:
        app: httpd-dm
    spec:
      terminationGracePeriodSeconds: 60
      restartPolicy: Always
      containers:
      - name: httpd
        image: httpd:alpine
        imagePullPolicy: IfNotPresent
        volumeMounts:
        - name: storage-localpv
          mountPath: "/usr/local/apache2/htdocs"
      volumes:
      - name: storage-localpv
        persistentVolumeClaim: claimName: local-pvc-sda
---
apiVersion: v1
kind: Service
metadata:
    name: httpd-svc
    namespace: in-demo
spec:
  ports:
    - name: http-port
      port: 80
      targetPort: 80
  selector:
    app: httpd-dm