StateFulSet+volumeClaimTemplates自动创建PV

nginx-statefulset.yaml

---
apiVersion: v1
kind: Service
metadata:
  name: nginx-headless
  labels:
    app: nginx
spec:
  ports:
  - port: 80
    name: web
  clusterIP: None   #注意此处的值,None表示无头服务
  selector:
    app: nginx
---
apiVersion: apps/v1beta1
kind: StatefulSet
metadata:
  name: web
spec:
  serviceName: "nginx"
  replicas: 2  #两个副本
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: ikubernetes/myapp:v1
        ports:
        - containerPort: 80
          name: web
        volumeMounts:
        - name: www
          mountPath: /usr/share/nginx/html
  volumeClaimTemplates:
  - metadata:
      name: www
      annotations:
        volume.beta.kubernetes.io/storage-class: "managed-nfs-storage"   #managed-nfs-storage为我们创建的storage-class名称
    spec:
      accessModes: [ "ReadWriteOnce" ]
      resources:
        requests:
          storage: 1Gi

检查结果:

集群节点上

 [root@k8s-master-155-221 classStorage]#kubectl delete -f nginx-statefulset.yaml 
[root@k8s-master-155-221 classStorage]# kubectl get pods -l app=nginx  #检查pod状态
NAME    READY   STATUS    RESTARTS   AGE
web-0   1/1     Running   0          115m
web-1   1/1     Running   0          114m
[root@k8s-master-155-221 classStorage]# kubectl get pvc #查看PVC
NAME         STATUS   VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS          AGE
test-claim   Bound    pvc-aae2b7fa-377b-11ea-87ad-525400512eca   1Mi        RWX            managed-nfs-storage   19h
www-web-0    Bound    pvc-4d7e342a-3810-11ea-87ad-525400512eca   1Gi        RWO            managed-nfs-storage   115m
www-web-1    Bound    pvc-5431c8ba-3810-11ea-87ad-525400512eca   1Gi        RWO            managed-nfs-storage   115m
[root@k8s-master-155-221 classStorage]# kubectl get pv #查看PV
NAME                                       CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS   CLAIM                STORAGECLASS          REASON   AGE
pvc-4d7e342a-3810-11ea-87ad-525400512eca   1Gi        RWO            Delete           Bound    default/www-web-0    managed-nfs-storage            115m
pvc-5431c8ba-3810-11ea-87ad-525400512eca   1Gi        RWO            Delete           Bound    default/www-web-1    managed-nfs-storage            115m
pvc-aae2b7fa-377b-11ea-87ad-525400512eca   1Mi        RWX            Delete           Bound    default/test-claim   managed-nfs-storage            19h

NFS Server上:

[root@nginx-keepalived-155-227 ~]# cd /data/volumes/
[root@nginx-keepalived-155-227 volumes]# ll  #注意目录的命名格式
总用量 0
drwxrwxrwx 2 root root 21 2020-01-15 17:51 default-test-claim-pvc-aae2b7fa-377b-11ea-87ad-525400512eca
drwxrwxrwx 2 root root  6 2020-01-16 11:28 default-www-web-0-pvc-4d7e342a-3810-11ea-87ad-525400512eca
drwxrwxrwx 2 root root  6 2020-01-16 11:28 default-www-web-1-pvc-5431c8ba-3810-11ea-87ad-525400512eca
[root@nginx-keepalived-155-227 volumes]# echo "web-00" > default-www-web-0-pvc-4d7e342a-3810-11ea-87ad-525400512eca/index.html #分别创建不同的index文件
[root@nginx-keepalived-155-227 volumes]# echo "web-01" > default-www-web-1-pvc-5431c8ba-3810-11ea-87ad-525400512eca/index.html

集群任意节点上:

[root@k8s-master-155-221 classStorage]# kubectl exec -it pod-cm-1 -- /bin/sh  #进入集群中任意pod中,解析nginx-headless 服务/ # nslookup nginx-headless
nslookup: can't resolve '(null)': Name does not resolve

Name:      nginx-headless
Address 1: 172.17.136.7 172-17-136-7.nginx-headless.default.svc.cluster.local  #可以看到有两个地址
Address 2: 172.17.248.5 172-17-248-5.nginx-headless.default.svc.cluster.local
[root@k8s-master-155-221 classStorage]# curl 172.17.248.5 #分别访问一下查看结果
web-00
[root@k8s-master-155-221 classStorage]# curl 172.17.136.7
web-01

对于statefulset我们可以通过添加/删除pod副本的数量,观察PV/PVC的状态及变化.