Setting up OpenLDAP on CentOS
I'm doing this using Ansible but here are some notes on what I've learned.
This service is the actual ldap service and it uses a seemingly complicated database called hdb or mdb.
CentOS 7 uses the deprecated hdb format.
The package on CentOS 7 automatically generates a slapd database in /etc/openldap/slapd.d based on the file /usr/share/openldap-servers/slapd.ldif. This would be step #9 in the OpenLDAP guide linked below.
So my recommendation is to purge that database after package install and make your own using slapadd.