External storage that read ibay with Nethserver user/password authentication
Permissions to these external storage are inherited directly from the data access permissions on ibays
so you need to work on ibay permissions by creating the correct groups and not assign the groups in the external storage configuration as you could do in Nextcloud 18
there is a case that if you go to put users (and only users, not groups) in the configuration of external storage, they take over the data permissions on ibay and accesses only have them from nextcloud
so if you want some users to be able to access ibay from smb but not from nextcloud via remote storage, forget it.
unwanted effect: you created a user directly in Nextcloud (not in Nethserver) and gave him permission to access an external storage/ibay (by configuring the access with another fixed netserver user): when that user accesses Nextcloud he also sees all the other external storage/ibay configured (which is not nice at all) without having access to it.
Simply: you can no longer manage ibay access with Nethserver groups from the external storage configuration panel in nextcloud 19 as you could in nextcloud 18