samba - Nov 2018 - Howto enable ldapi socket?

Hi list,

Im playing around with ldbsearch/ldapsearch and using successful the socket

/var/lib/samba/private/ldapi 

in my git-compiled samba.

Now I installed the version 4.9.2 for ubuntu bionic from the van-Belle
repository and didnt find this socket anymore. Do I have simple to
create this socket? How can I determine the path? Is there a
smb.conf-Option to enable it?

Tfh!

Oliver