New DataStore Path

Hello,

I dont have any idea, how to create a new local path,
I have mounted big path /mnt, and would like to create
i opennebula GUI inteface like this:

Filesystem: -ssh mode
Datastore Type: Images
Restricted directories for registering Images: /mnt
Safe directories for registering Images: /mnt

But finalized i have path the same dir: /var/lib/one/datastores/…

Well, How to create the right path to /mnt or default path to /mnt

Thanks, a lot