I have successfully managed to configure my OpenLDAP (which is an Apple Open Directory variant, but that should not matter) to work with both, SSL (ldaps on port 636) as well as STARTTLS (on port 389).
However, it's still possible for a client to connect without any encryption, and I'm trying to disable that. Admittedly, I have only very limited knowledge of OpenLDAP.
Based on this this answer and this tutorial, I tried it with
dn: olcDatabase={1}bdb,cn=config
changetype: modify
add: olcSecurity
olcSecurity: tls=1
After I had applied this to my ldap, attempts to connect without STARTTLS were indeed rejected. However, I was unable to authenticate any more, getting
LDAP: error code 50 - Insufficient Access Rights
Anonymous access works, but I when I test authentication of a user, I get the same above error.
Once I revert my changes (= delete the olcSecurity entry), everything is back to normal.
It looks like my change affected the access authorization, but I don't understand how this is connected, and what might be wrong.
