Some basic hints to configure the OpenLDAP server:
Size limit: OpenLDAP allows by default 500 return values per search, if you have more users/groups/hosts change this in slapd.conf: e.g. "sizelimit 10000" or "sizelimit -1" for unlimited return values.
Indices: Indices will improve the performance when searching for entries in the LDAP directory. The following indices are recommended:
| index objectClass eq |
| index default sub |
| index uidNumber eq |
| index gidNumber eq |
| index memberUid eq |
| index cn,sn,uid,displayName pres,sub,eq |
| # Samba 3.x |
| index sambaSID eq |
| index sambaPrimaryGroupSID eq |
| index sambaDomainName eq |