Create a File Storage file system in a Virtual Cloud Network (VCN) in Oracle Cloud Infrastructure.

To create a file system:

1. Configure a VCN for the File Storage file system. The precise configuration of the VCN varies. For example scenarios, see the Oracle Cloud Infrastructure documentation.

2. Create a File Storage file system. For more information, see the Oracle Cloud Infrastructure documentation.

3. Create a File Storage mount target to enable network access to the file system. For more information, see the Oracle Cloud Infrastructure documentation.

4. In Oracle Cloud Infrastructure, find and make a note of the following file system attributes. These are needed when you create YAML files or mount the file system in this example:

   • The OCID of the file system.

   • The export path of the file system. This example assumes you're setting the export path to /my-fss-export.

   • The mount commands. These commands are provided on the Mount Commands page of the File System. You use these commands later in the example when mounting the exported file system.

   • The IP address of the mount target.

To create a test application to use an Oracle Cloud Infrastructure File Storage file system:

1. Create a PersistentVolume file. On a control plane node, create a file called fss-pv.yaml with the following contents:

   apiVersion: v1
   kind: PersistentVolume
   metadata:
     name: fss-pv
   spec:
     capacity:
       storage: 50Gi
     volumeMode: Filesystem
     accessModes:
       - ReadWriteMany
     persistentVolumeReclaimPolicy: Retain
     csi:
       driver: fss.csi.oraclecloud.com
       volumeHandle: <filesystem_OCID>:<mount_target_IP>:<mount_target_export_path>

   The accessModes for the file system must be ReadWriteMany.

   The storage option is a Kubernetes requirement and must be included. The File Storage service ignores this value and creates a new file system with a default size, regardless of the value you specify for storage.

   The volumeHandle consists of a colon separated list of File Storage file system attributes, noted in an earlier step. For example:

   ocid1.filesystem.oc1.iad.aaaa...:10.0.0.200:/my-fss-export

2. Create the PersistentVolume.

   kubectl apply -f fss-pv.yaml

3. Get a list of the PersistentVolumes.

   kubectl get pv

   The output looks similar to:

   NAME     CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS      CLAIM   STORAGECLASS   REASON   AGE
   fss-pv   50Gi       RWX            Retain           Available                                   47s

4. Create a PersistentVolumeClaim file. Create a file called fss-pvc.yaml. Copy the following into the file:

   apiVersion: v1
   kind: PersistentVolumeClaim
   metadata:
     name: fss-pvc
   spec:
     accessModes:
       - ReadWriteMany
     storageClassName: ""
     resources:
       requests:
         storage: 5Gi
     volumeName: fss-pv

   The accessModes for the file system must be ReadWriteMany.

   The storage option is a Kubernetes requirement and must be included. The File Storage service ignores this value and creates a new file system with a default size, regardless of the value you specify for storage.

   The volumeName is set to the name attribute in the PersistentVolume file fss-pv.yaml.

5. Create the PersistentVolumeClaim.

   kubectl apply -f fss-pvc.yaml

6. Get a list of PersistentVolumeClaims.

   kubectl get pvc

   The output looks similar to:

   NAME      STATUS   VOLUME   CAPACITY   ACCESS MODES   STORAGECLASS   AGE
   fss-pvc   Bound    fss-pv   50Gi       RWX                           33s

7. Create a pod manifest file. Create a file called fss-pod.yaml. Copy the following into the file:

   apiVersion: v1
   kind: Pod
   metadata:
     name: app
   spec:
     containers:
     - name: app
       image: container-registry.oracle.com/os/oraclelinux:9-slim
       command: ["/bin/sh"]
       args: ["-c", "while true; do echo $(date -u) >> /data/out.txt; sleep 5; done"]
       volumeMounts:
       - name: persistent-storage
         mountPath: /data
     volumes:
     - name: persistent-storage
       persistentVolumeClaim:
         claimName: fss-pvc

   The image option specifies the registry location to an Oracle Linux container image.

   The mountPath option specifies the directory mounted to the persistent storage.

   The command option specifies a command to write to file out.txt in the /data directory.

8. Create the pod.

   kubectl apply -f fss-pod.yaml

9. Get a list of the pods.

   kubectl get pods

   The output looks similar to:

   NAME   READY   STATUS    RESTARTS   AGE
   app    1/1     Running   0          21s

10. Open a shell to the container within the pod:

    kubectl exec -i -t app --container app -- /bin/bash

11. From the container's shell, confirm the container is writing to the /data/out.txt file by using the tail command:

    tail -f /data/out.txt

    The date and time output of the date -u command is listed to the terminal and written to the /data/out.txt file on the container. Exit the tail program by using CTRL+C.

12. Exit the container shell using the exit command:

    exit

13. Verify that the /data directory within the container is mounted to the file system export path. This step uses the mount commands noted when you created the file system.

    1. On the control plane node, install the NFS client.

       sudo dnf install nfs-utils

    2. Create and mount a local directory to the file system's export path.

       sudo mkdir -p /mnt/my-fss-export
       sudo mount 10.0.0.200:/my-fss-export /mnt/my-fss-export

       Replace 10.0.0.200 with the IP address of the mount target.

    3. Confirm the output.txt file the container is writing to is in the file system's export path. You can use the tail command for this:

       sudo tail -f /mnt/my-fss-export/out.txt

       The date and time being written to the file by the pod is listed. Exit the tail program by using CTRL+C.

14. Delete the pod. If you don't see the command prompt after the pod is deleted you can use the CTRL+C key combination to get it back:

    kubectl delete pod app

15. Delete the PersistentVolumeClaim:

    kubectl delete pvc fss-pvc

16. Confirm that the status of the PersistentVolume is Released:

    kubectl get pv

    The output looks similar to:

    NAME     CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS     CLAIM             STORAGECLASS   REASON   AGE
    fss-pv   50Gi       RWX            Retain           Released   default/fss-pvc                           57m

17. Delete the PersistentVolume:

    kubectl delete pv fss-pv

18. Confirm the file is still present:

    ls -l  /mnt/my-fss-export/out.txt

19. Remove the mount:

    sudo umount /mnt/my-fss-export

20. Confirm the out.txt file is no longer available and the mount is removed:

    ls -l /mnt/my-fss-export

21. Confirm the /mnt/my-fss-export is no longer mounted:

    mount | grep my-fss-export