Mount disks and SMB file systems to Windows pods

Create and mount disk volumes to Windows pods

Alibaba Cloud disks are block storage resources for Elastic Compute Service (ECS) instances. Alibaba Cloud disks provide low latency, high performance, high durability, and high reliability.

You can perform the following steps to create and mount disk volumes to Windows pods:

Step 1: Create a StorageClass

By default, if FlexVolume is selected as the volume plug-in, the system defines StorageClasses that are intended for the Linux file system when you create an ACK cluster. You must manually define StorageClasses intended for the Windows file system.

1. Create a file named storageclass.yaml based on the following content to define StorageClasses for the Windows file system:
   YAML example

   kind: StorageClass
   apiVersion: storage.k8s.io/v1
   metadata:
     name: alicloud-disk-common-windows
   provisioner: alicloud/disk
   parameters:
     type: cloud
     fstype: ntfs
   ---
   kind: StorageClass
   apiVersion: storage.k8s.io/v1
   metadata:
     name: alicloud-disk-efficiency-windows
   provisioner: alicloud/disk
   parameters:
     type: cloud_efficiency
     fstype: ntfs
   ---
   kind: StorageClass
   apiVersion: storage.k8s.io/v1
   metadata:
     name: alicloud-disk-ssd-windows
   provisioner: alicloud/disk
   parameters:
     type: cloud_ssd
     fstype: ntfs
   ---
   kind: StorageClass
   apiVersion: storage.k8s.io/v1
   metadata:
     name: alicloud-disk-essd-windows
   provisioner: alicloud/disk
   parameters:
     type: cloud_essd
     fstype: ntfs
   ---
   kind: StorageClass
   apiVersion: storage.k8s.io/v1
   metadata:
     name: alicloud-disk-available-windows
   provisioner: alicloud/disk
   parameters:
     type: available
     fstype: ntfs
   	  

   The following table describes the configurations of the StorageClasses.

   YAML example	Description
   kind: StorageClass apiVersion: storage.k8s.io/v1 metadata: name: alicloud-disk-ssd-windows provisioner: alicloud/disk parameters: type: cloud_ssd fstype: ntfs + allowVolumeExpansion: true # useless	Volume expansion is not supported in Windows. For example, the allowVolumeExpansion: true configuration of the StorageClass does not take effect.
   kind: StorageClass apiVersion: storage.k8s.io/v1 metadata: name: alicloud-disk-ssd-windows provisioner: alicloud/disk parameters: type: cloud_ssd fstype: ntfs + reclaimPolicy: Retain # only unmount	You can configure the reclaimPolicy: Retain reclaim policy to reduce the chances of accidental data loss by user errors.
   kind: StorageClass apiVersion: storage.k8s.io/v1 metadata: name: alicloud-disk-ssd-windows provisioner: alicloud/disk parameters: type: cloud_ssd fstype: ntfs + regionId: cn-hangzhou + zoneId: cn-hangzhou-b	If no region ID or zone ID is specified, the system may fail to mount the disk. You can set the regionId and zoneId parameters to prevent mounting errors.

2. Run the following command to create a StorageClass in the Windows environment:

   kubectl create -f storageclass.yaml

Step 2: Install FlexVolume on Windows nodes

1. Use the following YAML template to create a flexvolume-windows.yaml file.
   YAML example

   apiVersion: apps/v1
   kind: DaemonSet
   metadata:
     labels:
       app: flexvolume-windows
     name: flexvolume-windows
     namespace: kube-system
   spec:
     selector:
       matchLabels:
         k8s-volume: flexvolume
     updateStrategy:
       type: RollingUpdate
     template:
       metadata:
         metadata:
         labels:
           k8s-volume: flexvolume
         annotations:
           scheduler.alpha.kubernetes.io/critical-pod: ""
       spec:
         tolerations:
         - operator: Exists
         /*since 1.18, we can specify "hostNetwork: true" for Windows workloads, so we can deploy an application without NetworkReady.*/
         hostNetwork: true
         priorityClassName: system-node-critical
         affinity:
           nodeAffinity:
             requiredDuringSchedulingIgnoredDuringExecution:
               nodeSelectorTerms:
               - matchExpressions:
                 - key: type
                   operator: NotIn
                   values:
                   - virtual-kubelet
                 - key: beta.kubernetes.io/os
                   operator: In
                   values:
                   - windows
               - matchExpressions:
                 - key: type
                   operator: NotIn
                   values:
                   - virtual-kubelet
                 - key: kubernetes.io/os
                   operator: In
                   values:
                   - windows
         containers:
         - name: acs-flexvolume
           command:
           - pwsh.exe
           - -NoLogo
           - -NonInteractive
           - -File
           - entrypoint.ps1
           /* Replace cn-hangzhou in the following image address with the region where your cluster is deployed. */
           image: registry-vpc.cn-hangzhou.aliyuncs.com/acs/flexvolume-windows:v1.0.0
           imagePullPolicy: Always
           volumeMounts:
           - name: host-flexvolume-binary
             mountPath: c:/host/usr/libexec/kubernetes/kubelet-plugins/volume/exec
           - name: host-flexvolume-socket
             mountPath: c:/host/etc/kubernetes/flexvolume/socket
           - name: host-log
             mountPath: c:/var/log/alicloud
           /*use managed addon token from Alibaba Cloud*/
           - name: managed-addon-token
             mountPath: c:/var/addon/
             readOnly: true
        /* or specify the customized access key of Alibaba Cloud*/
        /* - name: customized-access-key*/
        /*   mountPath: c:/host/etc/.volumeak*/
        /* env:*/
        /* - name: ACCESS_KEY_ID*/
        /*   value: ""*/
        /* - name: ACCESS_KEY_SECRET*/
        /*   value: ""*/
         volumes:
         - name: host-flexvolume-binary
           hostPath:
             path: c:/usr/libexec/kubernetes/kubelet-plugins/volume/exec
             type: DirectoryOrCreate
         - name: host-flexvolume-socket
           hostPath:
             path: c:/etc/kubernetes/flexvolume/socket
             type: DirectoryOrCreate
         - name: host-log
           hostPath:
             path: c:/var/log/alicloud
             type: DirectoryOrCreate
         - name: managed-addon-token
           secret:
             defaultMode: 420
             optional: true
             items:
             - key: addon.token.config
               path: token-config
             secretName: addon.csi.token
        /* - name: customized-access-key*/
        /*   hostPath:*/
        /*     path: c:/etc/.volumeak*/
        /*     type: DirectoryOrCreate*/
      

2. Run the following command to install FlexVolume on all of the Windows worker nodes:

   kubectl create -f flexvolume-windows.yaml

3. After the DaemonSets are deployed, run the following command on a Windows node to query the status of the FlexVolume plug-in alicloud-disk-controller:

   ls C:\usr\libexec\kubernetes\kubelet-plugins\volume\exec\alicloud~disk.exe\

   Expected output:

   Directory: C:\usr\libexec\kubernetes\kubelet-plugins\volume\exec\alicloud~disk.exe
   
   Mode                LastWriteTime         Length Name
   ----                -------------         ------ ----
   -a----        8/12/2021   2:45 PM        5636096 disk.exe

Step 3: Create a disk volume and mount it to a Windows pod

A StatefulSet is used as an example. You can specify the required StorageClass in the volumeClaimTemplates field. Then, the FlexVolume plug-in on the Windows worker node automatically performs the following operations: verifies your credentials, creates a disk, attaches the disk to an ECS instance, and then creates and mounts a disk volume to a Windows pod.

apiVersion: v1
kind: Service
metadata:
  labels:
    app: web-windows-disk
  name: web-windows-disk
spec:
  type: LoadBalancer
  ports:
    - port: 80
      protocol: TCP
      targetPort: 80
  selector:
    app: web-windows-disk
---
apiVersion: v1
kind: Service
metadata:
  name: web-windows-disk-headless
  labels:
    app: web-windows-disk
spec:
  ports:
  - port: 80
    protocol: TCP
    targetPort: 80
  clusterIP: None
  selector:
    app: web-windows-disk
---
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: web-windows-disk
spec:
  serviceName: "web-windows-disk-headless"
  selector:
    matchLabels:
      app: web-windows-disk
  replicas: 1
  template:
    metadata:
      labels:
        app: web-windows-disk
    spec:
      restartPolicy: Always
      terminationGracePeriodSeconds: 30
      tolerations:
      - key: os
        value: windows
      affinity:
        nodeAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
            nodeSelectorTerms:
            - matchExpressions:
              - key: beta.kubernetes.io/os
                operator: In
                values:
                - windows
            - matchExpressions:
              - key: kubernetes.io/os
                operator: In
                values:
                - windows
      containers:
      - name: windows
        /* Replace cn-hangzhou in the following image address with the region where your cluster is deployed. */
        image: registry-vpc.cn-hangzhou.aliyuncs.com/acs/sample-web-windows:v1.0.1
        volumeMounts:
          - name: ssd
            mountPath: c:/openresty/logs
  volumeClaimTemplates:
  - metadata:
      name: ssd
    spec:
      accessModes: 
      - ReadWriteOnce
      /* Specify the supported disk type based on the zone and region where your cluster is deployed. */
      storageClassName: alicloud-disk-ssd-windows
      resources:
        requests:
          storage: 50Gi 
   

kubectl get pv

NAME                     STATUS   VOLUME                   CAPACITY   ACCESS MODES   STORAGECLASS                AGE
ssd-web-windows-disk-0   Bound    d-wz9dihqdkusysc56****   50Gi       RWO            alicloud-disk-ssd-windows   5s

Step 4: Verify that the disk volume can be used to persist data

Create and mount SMB volumes to Windows pods

Apsara File Storage NAS (NAS) is a distributed file system that is provided for ECS instances. NAS uses Portable Operating System Interface of UNIX (POSIX)-based APIs and is compatible with native operating systems. NAS provides shared access, ensures data consistency, and implements mutual exclusion by using locks.

SMB is a protocol that can be used by NAS and works well in Windows. Different from alicloud-disk-controller, the SMB FlexVolume plug-in is not reliant on Linux worker nodes or Kubernetes controllers.

If Kubernetes controllers are not used, the SMB FlexVolume plug-in can only statically provision PVs and cannot use StorageClasses to dynamically provision PVs.

Step 1: Install FlexVolume on Windows nodes

Install FlexVolume on all of the Windows worker nodes. For more information, see Step 2: Install FlexVolume on Windows nodes of Create and mount disk volumes to Windows pods.

Step 2: Create an SMB PV and mount the PV to a Windows pod

1. Create a PV.
   Use the following YAML template to create a PV and a persistent volume claim (PVC), and apply for a NAS file system of 10 GiB in size.

   YAML example

   apiVersion: v1
   kind: PersistentVolume
   metadata:
     labels:
       alicloud-pvname: pv-smb-10g
     name: pv-smb-10g
   spec:
     persistentVolumeReclaimPolicy: Retain
     accessModes:
     - ReadWriteMany
     capacity:
       storage: 10Gi
     flexVolume:
       driver: alicloud/smb.exe
       options:
         server: 25f3f4819c-e****.cn-hangzhou.nas.aliyuncs.com
         path: /myshare/web-windows-logs
         user: workgroup/Administrator
         password: ******
   ---
   apiVersion: v1
   kind: PersistentVolumeClaim
   metadata:
     name: web-windows-smb
   spec:
     selector:
       matchLabels:
         alicloud-pvname: pv-smb-10g
     accessModes:
     - ReadWriteMany
     resources:
       requests:
         storage: 10Gi
      

   The following table describes some of the parameters in the template.

   Parameter	Description
   driver	The type of driver that is used to mount the PV. The value must be set to alicloud/smb.exe.
   server	The mount address of the mount target that is added for the NAS file system. The region of the mount address must be the same as that of the virtual private cloud (VPC) where the Windows nodes are deployed.
   path	The path where the NAS file system is mounted in the container. The path must start with /myshare/. This means that all the subdirectories are created under the parent directory /myshare/. Example: /myshare/web-windows-logs.
   user	The username used to log on to the ECS instance. We recommend that you use workgroup/administrator.
   password	The password used to log on to the ECS instance.

2. Use the following YAML template to create a Service and a Deployment, and mount the created PV.
   YAML example

   apiVersion: v1
   kind: Service
   metadata:
     labels:
       app: web-windows-smb
     name: web-windows-smb
   spec:
     type: LoadBalancer
     ports:
       - port: 80
         protocol: TCP
         targetPort: 80
     selector:
       app: web-windows-smb
   ---
   apiVersion: apps/v1
   kind: Deployment
   metadata:
     name: web-windows-smb
   spec:
     selector:
       matchLabels:
         app: web-windows-smb
     replicas: 1
     template:
       metadata:
         labels:
           app: web-windows-smb
       spec:
         restartPolicy: Always
         terminationGracePeriodSeconds: 30
         tolerations:
         - key: os
           value: windows
         affinity:
           nodeAffinity:
             requiredDuringSchedulingIgnoredDuringExecution:
               nodeSelectorTerms:
               - matchExpressions:
                 - key: beta.kubernetes.io/os
                   operator: In
                   values:
                   - windows
               - matchExpressions:
                 - key: kubernetes.io/os
                   operator: In
                   values:
                   - windows
         containers:
         - name: windows
           /* Replace cn-hangzhou in the following image address with the region where your cluster is deployed. */
           image: registry-vpc.cn-hangzhou.aliyuncs.com/acs/sample-web-windows:v1.0.1
           volumeMounts:
             - name: disk-smb
               mountPath: c:/openresty/logs
         volumes:
         - name: disk-smb
           persistentVolumeClaim:
             claimName: web-windows-smb
      

3. After the Deployment is deployed, run the following commands to query the Deployment of the application and the PV.
   • Run the following command to query the Deployment:

     kubectl get pod

     Expected output:

     NAME                               READY   STATUS              RESTARTS   AGE
     web-windows-smb-584676df65-t4mmh   1/1     Running             0          26d

   • Run the following command to query the PV:

     kubectl get pv

     Expected output:

     NAME         CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS      CLAIM                       STORAGECLASS      REASON   AGE
     pv-smb-10g   10Gi       ReadWriteMany  Retain           Bound       default/web-windows-smb                                10d

Step 4: Verify that the NAS file system can be used to persist data