If all you are doing is trying to connect securely, we default to using startTLS, the RFC defined method for doing secure communications over the LDAP protocol. LDAPS was a scheme that was done with LDAPv2 because there was no official method for doing secure connections over the LDAP protocol. There's generally never a reason to use LDAPS instead of LDAP as long as you are using startTLS. If you change your configuration to use LDAPS, you're going to have to modify everything that was set to use startTLS to stop using it, since the two are not compatible.
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