A more secure alternative to NFS or SAMBA would be to use SSHFS.
Besides encrypting the data stream, it has many benefits, among which:
- Firewall-friendly, since it uses standard SSH ports
- Supports PKI
To mount an SSH filesystem from Ubuntu, do the following:
sudo apt install sshfs
sudo mkdir /MountPoint
sudo sshfs username@server:/RemoteFileSystem /MountPoint
Note: You don’t need to use sudo to mount via sshfs, just make sure you have permissions on the local mount point.