"Operation not permitted" when accessing a NFS mounted directory inside a docker container

Question

I am working on a Web-App which needs access to a QNAP-NAS file system to edit and create directories and files inside it.

In order to mount the NFS to the docker container, I used the following docker compose file:

services:
  app:
    ... # Irrelevant stuff
    volumes:
      - .:/app 
      - "nfs-base:/Z" # Mount the nfs volume to the /base directory in the container

volumes:
  nfs-base:
    driver: local
    driver_opts:
      type: nfs
      o: "nfsvers=4,addr=IPADDRESS_OF_THE_QNAP-NAS,rw"
      device: ":/"

I get no error when creating the volume, and inspecting the container, the :/Z/base directory gets created, which means the shared folder base of the qnap-filesystem is propperly mounted, or at least recognised by the docker-compose file.

The problem comes when I inspect the container content to review if the files inside :/Z/base are properly mounted.

When I access the /base directory inside the container, I get the error: bash: cd: base/base: Operation not permitted.

I would like to add that when I check the permission of the folder inside the container, I get this prompt:

drwxrwxrwx 28 1000 root 4096 May 10 09:04 base

I guess it's an issue that comes from permissions to access to the shared folder, but as I am new to the QNAP, i don't know how to give that permissions.

Note that if I access the QNAP-NAS /base directory from the same host where I have the docker container via ssh, I have no problems with permissions ( I can access all the files in the base directory).

How can I give permissions to the docker container to read/write to a NFS mounted directory?

Answer 1

Finally, I managed to mount the shared folder.

For all of those with the same problem, I achieved it by deactivating the "secure" option in the QNAP Control panel --> Edit Shared Folder Permissions --> Permission type = NFS host access

Hope it helps!

Joan