我们使用Helm安装prometheus-operator后，监控的数据默认是保存在Pod中的，那么当我们的Pod进行重启或者调度之后， 就会出现无法查看历史数据，所以我们需要对数据进行持久化保存

1. 首先创建一个NFS服务供我们的kubernetes集群使用。

   [root@localhost ~]# yum -y install nfs-utils
   [root@localhost ~]# cat /etc/exports
    /tmp/data/	*(rw,fsid=1,sync,no_root_squash)	
    #重新加载nfs配置信息
    [root@localhost ~]# exportfs -rv
   

2. 将nfs配置为kubernetes可使用的storageClass.

kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
 name: nfs-provisioner-runner
rules:
 - 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-provisioner
subjects:
 - kind: ServiceAccount
   name: nfs-provisioner
   namespace: default
roleRef:
 kind: ClusterRole
 name: nfs-provisioner-runner
 apiGroup: rbac.authorization.k8s.io
---
kind: Role
apiVersion: rbac.authorization.k8s.io/v1
metadata:
 name: leader-locking-nfs-provisioner
rules:
 - apiGroups: [""]
   resources: ["endpoints"]
   verbs: ["get", "list", "watch", "create", "update", "patch"]
---
kind: RoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
 name: leader-locking-nfs-provisioner
subjects:
 - kind: ServiceAccount
   name: nfs-provisioner
   namespace: default
roleRef:
 kind: Role
 name: leader-locking-nfs-provisioner
 apiGroup: rbac.authorization.k8s.io
---
apiVersion: v1
kind: ServiceAccount
metadata:
 name: nfs-provisioner
---
kind: Deployment
apiVersion: extensions/v1beta1
metadata:
 name: nfs-provisioner
spec:
 replicas: 1
 strategy:
   type: Recreate
 template:
   metadata:
     labels:
       app: nfs-provisioner
   spec:
     serviceAccount: nfs-provisioner
     containers:
       - name: nfs-provisioner
         image: registry.cn-hangzhou.aliyuncs.com/open-ali/nfs-client-provisioner
         volumeMounts:
           - name: nfs-client-root
             mountPath: /persistentvolumes
         env:
           - name: PROVISIONER_NAME
             value: example.com/nfs
           - name: NFS_SERVER
             value: 192.168.1.112
           - name: NFS_PATH
             value: /tmp/data/
     volumes:
       - name: nfs-client-root
         nfs:
           server: 192.168.1.112
           path: /tmp/data/
---
kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
 name: prometheus
provisioner: example.com/nfs

代码中的env与Volumes中的配置修改为自己实际信息。

kubernetes apply -f storageclass.yaml 
[root@master ~]# kubectl get sc
NAME         PROVISIONER       AGE
prometheus   example.com/nfs   18d

如上信息，表示我们的StorageClass创建已经成功

3. 接下来我们修改helm中prometheus中的数据存储信息
   修改StorageSpec的配置信息如下，关于storageClassName可根据实际修改

    storageSpec:
      volumeClaimTemplate:
        spec:
          storageClassName: prometheus
          accessModes: ["ReadWriteOnce"]
          resources:
            requests:
              storage: 50Gi

4. 安装prometheus-operator

 helm install --name my-release stable/prometheus-operator -f prometheus-config.yaml

如上，我们已经配置好prometheus-operator的数据持久化了