LDAP - Apache Directory Studio

Is it possible to connect the Nextcloud to a LDAP Directory like the Apache Directory?

I set up some users and groups following this tutorial:

At the end of this tutorial there are LDIF files, which are very similar to mine except I use password encryption SSHA.

But connecting the Nextcloud to it didn’t work for me.

From my server I can do an successful ldapsearch for the DN.

I setup an openldap directory directly on the Server, now the Port is detected without problems. But somehow attributs seem to count as users, but real users are not to be found at least not be “uid”.

What are the attributes Nextcloud need to have to work in a separated group on an openldap directory (with Active Directory every thing looks fine!) ???