I guess it is a problem of terminology, I should have use baseDN I guess.

--On Monday, October 2, 2023 12:47 PM +0200 Jérôme BECOT <jerome.becot@deveryware.com> wrote:

Hello,

It is not possible to have two different DN on the same database, because
the rootDN is unique. But you can configure multiple databases on the
same server, that works quite independently (every db has its own set of
overlays/config/replication). When you create the databases, you must
ensure that they don't live in the same directory (defaults to
/var/lib/ldap).

There's no need for it to be a rootdn, generally I suggest avoiding using the rootdn for backends at all.  The only rootdn that *might* need to be used is the one for cn=config, but that's entirely separate.

--Quanah