k8s volume mount overwrite

The work directory of my docker image is set to "/opt",and it will contain the jar file and config files,etc. I am trying to mount it pvc in k8s, but find the pvc will overwrite the /opt directory.Is there any way to mount the directory in docker image which is not empty , Thanks.

When a PVC is mounted to a directory, instead of adding a new file it will overwrite the directory you specify. For your case when the PVC is mounted the directory “/opt” will be replaced. To prevent this you need to create a new directory within the /opt directory or you can mount PVC to a different directory other than the current directory.

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: my-pvc
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 10Gi
  storageClassName: standard
  volumeMode: Filesystem
  volumeName: my-pvc
  mountPath: "/opt/my-pvc"

This YAML will create a new directory named 'my-pvc' within the '/opt' directory and mount the PVC to it. Any files that are already in the '/opt' directory will not be overwritten.

Or else:

mountOptions:
    - path: /mnt

This will mount the PVC to the /mnt directory instead of /opt, so the data in /opt will not be overwritten.

This blog by Iman Tumorang will help you for reference.

there are any files in the /opt directory in the Docker image, they will be overridden by the contents of the PVC when the PVC is mounted to the directory. To avoid this, you may want to copy the files from the /opt directory to a subdirectory within /opt during container startup, and then mount the PVC to the parent directory.