Issue to share local folder

Nextcloud version (eg, 10.0.2): 12
Operating system and version (eg, Ubuntu 16.04): Ubuntu 16.04
Apache or nginx version (eg, Apache 2.4.25): Apache/2.4.18
PHP version (eg, 5.6):PHP Version 7.0.18
Is this the first time you’ve seen this error?: yes

I have 2 VM on proxmox host last version
1 VM is with OMV to use like a NAS
1 VM for nextcloud

on my OMV vm I have a cifs share and permission for one user X to rw
If on nextcloud mount an external share with X credential and use this on my windows client, I can create, modify, delete what I want.
However I don’t go up to 200Mb/sec
If I install cifs-util and mount the share on the nextcloud vm and on external storage share it as local I can download what I have on my share and go up to 850Mb/sec
The issue with this last method is I can’t create nothing on my windows client because it’s writtent I don’t have rights…

I need to know what I have to do on my nextcloud VM to mount the smb share locally and share it with my client and they can modify it to test if speed is ok or not !

I follow this guide for my configuration

but don’t implement ssl or hide index.php