K8S后端存储：NFS
大家都知道，NFS是一种基于网络的文件系统协议，允许在不同的机器之间共享文件系统资源。在K8S中，可以使用NFS作为后端存储，以提供持久化存储和共享存储卷。但是否适合在生产环境使用NFS作为后端存储，这取决于具体的应用程序和使用场景。如果应用程序对性能和可靠性要求比较高，可能需要选择其他更适合的存储方案，比如ceph。如果只是在测试或者开发环境中，我觉得使用NFS可以更方便地实现共享存储卷，提高测试或者开发的效率。
搭建NFS
# step1 安装yum install nfs-utils -y yum install nfs-utils -y # step2 创建NFS共享目录 mkdir /data/nfs_k8s_storage_share # step3 配置NFS共享，编辑/etc/exports文件，将要共享的目录添加到文件中 /data/nfs_k8s_storage_share *(rw,sync,no_root_squash) # 这将允许任何客户端以读写模式访问共享目录。 # step4 重新加载NFS配置 exportfs -r # step5 启动NFS服务 systemctl start nfs-server systemctl enable nfs-server # step6 确认NFS服务正在运行 systemctl status nfs-server # step7 注意防火墙，可以关闭或添加允许策略 firewall-cmd --permanent --zone=public --add-service=nfs firewall-cmd --reload # step8 验证是否共享成功 showmount -e 192.168.11.254
k8s工作节点安装nfs-utils
安装完即可，无需做任何配置
yum install nfs-utils -y
“具体在哪个工作节点安装得看在下面的deployment.yaml中拉起的NFS客户端配置程序pod跑在哪个节点上，可以让该pod调度到指定的节点，那么该节点就要安装好nfs-utils。如果不干涉调度行为，或者考虑到后续要跑多个副本就可以将全部工作节点都安装好nfs-utils。
”
在k8s master节点上安装nfs动态供给插件
仓库： https://github.com/kubernetes-sigs/nfs-subdir-external-provisioner
相关yaml下载链接： https://github.com/kubernetes-sigs/nfs-subdir-external-provisioner/blob/master/deploy/rbac.yamlhttps://github.com/kubernetes-sigs/nfs-subdir-external-provisioner/blob/master/deploy/deployment.yamlhttps://github.com/kubernetes-sigs/nfs-subdir-external-provisioner/blob/master/deploy/class.yaml
- rbac.yaml：授权访问ApiServer
- deployment.yaml：部署插件，部署之前要修改里面的指向的nfs服务器地址和共享目录
- class.yaml：创建存储类
开始部署插件
- 部署rbac.yaml
apiVersion: v1 kind: ServiceAccount metadata: name: nfs-client-provisioner # replace with namespace where provisioner is deployed namespace: default --- kind: ClusterRole apiVersion: rbac.authorization.k8s.io/v1 metadata: name: nfs-client-provisioner-runner rules: - apiGroups: [""] resources: ["nodes"] verbs: ["get", "list", "watch"] - 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-client-provisioner subjects: - kind: ServiceAccount name: nfs-client-provisioner # replace with namespace where provisioner is deployed namespace: default roleRef: kind: ClusterRole name: nfs-client-provisioner-runner apiGroup: rbac.authorization.k8s.io --- kind: Role apiVersion: rbac.authorization.k8s.io/v1 metadata: name: leader-locking-nfs-client-provisioner # replace with namespace where provisioner is deployed namespace: default rules: - apiGroups: [""] resources: ["endpoints"] verbs: ["get", "list", "watch", "create", "update", "patch"] --- kind: RoleBinding apiVersion: rbac.authorization.k8s.io/v1 metadata: name: leader-locking-nfs-client-provisioner # replace with namespace where provisioner is deployed namespace: default subjects: - kind: ServiceAccount name: nfs-client-provisioner # replace with namespace where provisioner is deployed namespace: default roleRef: kind: Role name: leader-locking-nfs-client-provisioner apiGroup: rbac.authorization.k8s.io
kubectl create -f rbac.yaml
- 部署deployment.yaml
apiVersion: apps/v1 kind: Deployment metadata: name: nfs-client-provisioner labels: app: nfs-client-provisioner # replace with namespace where provisioner is deployed namespace: default spec: replicas: 1 strategy: type: Recreate selector: matchLabels: app: nfs-client-provisioner template: metadata: labels: app: nfs-client-provisioner spec: serviceAccountName: nfs-client-provisioner containers: - name: nfs-client-provisioner image: tantianran/nfs-subdir-external-provisioner:v4.0.1 # 使用到镜像已经转存到我的仓库 volumeMounts: - name: nfs-client-root mountPath: /persistentvolumes env: - name: PROVISIONER_NAME value: k8s-sigs.io/nfs-subdir-external-provisioner - name: NFS_SERVER value: 192.168.11.254 #此处修改成nfs服务器的ip地址 - name: NFS_PATH value: /data/nfs_k8s_storage_share # 此处修改成nfs的共享目录 volumes: - name: nfs-client-root nfs: server: 192.168.11.254 #此处修改成nfs服务器的ip地址 path: /data/nfs_k8s_storage_share # 此处修改成nfs的共享目录
kubectl create -f deployment.yaml
- 创建存储类class.yaml
apiVersion: storage.k8s.io/v1 kind: StorageClass metadata: name: nfs-client provisioner: k8s-sigs.io/nfs-subdir-external-provisioner # or choose another name, must match deployment's env PROVISIONER_NAME' parameters: archiveOnDelete: "false"
kubectl create -f class.yaml
- 查看
# 查看授权 kubectl get sa # 查看存储类 kubectl get sc
使用
- 创建一个PVC
apiVersion: v1 kind: PersistentVolumeClaim metadata: name: my-pvc spec: accessModes: - ReadWriteOnce resources: requests: storage: 5Gi storageClassName: nfs-client
在这里，PVC名称为my-pvc，请求5GB的存储空间，并将存储类设置为nfs-client
- 查看pvc
# pvc已创建 [root@k8s-a-master nfs-storage-yaml]# kubectl get pvc NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE my-pvc Bound pvc-ce18ae0a-d4b4-4fa9-8241-b8b9551baa61 5Gi RWO nfs-client 2m6s # 对应的pv已经自动创建 [root@k8s-a-master nfs-storage-yaml]# kubectl get pv NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE pvc-ce18ae0a-d4b4-4fa9-8241-b8b9551baa61 5Gi RWO Delete Bound default/my-pvc nfs-client 2m7s [root@k8s-a-master nfs-storage-yaml]#
- 创建一个应用pod
apiVersion: v1 kind: Pod metadata: name: test-nginx-pod spec: containers: - name: test-nginx-container image: nginx volumeMounts: - name: storage mountPath: /data volumes: - name: storage persistentVolumeClaim: claimName: my-pvc
- 查看pod是否挂载成功
[root@k8s-a-master nfs-storage-yaml]# kubectl exec -it test-nginx-pod -- df -h ... 3.9G 0 3.9G 0% /sys/fs/cgroup 192.168.11.254:/data/nfs_k8s_storage_share/default-my-pvc-pvc-ce18ae0a-d4b4-4fa9-8241-b8b9551baa61 500G 1.8G 499G 1% /data ...
