Set users home directory / different then their username


we have a phone system server that saves users voice mails into a directory (usr/local/pbx/voicemails)

inside voicemail, there is several directory- each Phone System user has their own directory - and the directory is the users domain name

now, i want to interconnect with OwnCloud, so users can login to OC and see their files, share it with others, sync it between devices etc

so, how will i accomplish this?
1) i planned on making "recordings" a NFS mount to the OwnCloud server
2) and when i add a user to OC, it will make that users home directory the specific domain folder inside "recordings", and the user shouldnt be able to change into another directory, outside from thier domain folder

but, when i add a user to OwnCloud, how can i specify which directory the user should have access to ?

Server configuration
Operating system:
Web server:
PHP version:
ownCloud version (see ownCloud admin page): 9.1.4
Updated from an older ownCloud or fresh install: fresh install
Special configuration (external storage, external authentication, reverse proxy, server-side-encryption):

ownCloud configuration

Go to the admin page, click on 'admin' -> 'Generate Config Report' -> 'Download ownCloud config report' or use the command line `sudo -u www-data php occ config:list system` (please sanitize sensitive data):

ownCloud log (data/owncloud.log)

Please paste possible errors in the following code block, see for more info

Integrity status for oC9+

No errors have been found.

You probably can mount different NFS shares at each user's directory. For internal storage, you can't easily change the structure how ownCloud manages users. It used to be possible to mount external storage as the user's home folder in the enterprise edition but I don't find the reference again.

Your second request is probably difficult. Not sure how this can be done on home storage. You could just use the default ownCloud storage and connect to NFS via external storages and you manage permissions there in a way you want them to be.

If the enterprise subscription is an option for you, their support can probably help you best, which of your goals can be achieved. On the community version, you probably have to live with a work around or start implementing it yourself.

i dont want to have to create a NFS mount for each user

rather, i want to create a user, and tell it where its home directory will be.
and they should not be able to access any folders above them (since if they do , then there will be a bunch of folders for each other user, which they will be able to see,. and i dont want them to see it)

This is currently not possible to achieve from within ownCloud.

does anyone have any ideas how i can accomplish it ?

Ideas are:

I looked at configuring external storage

seems like there is only an option to allow each user, to connect an external storage - this wont work since it requires the user to configure it etc...

unless if i missed it, can i specify what the home dir is ?
i actually enabled the plugin, but i dont see a button to add a external storage