Ldap with Open Directory & clear text password transmission


I’ve been using NextCloud (and previously OwnCloud) with our Open Directory setup (macOS 10.11 Server version 5.1) for quite some time, but when recently doing some security auditing found that passwords are being transmitted in clear text over the network between our NextCloud server and Open Directory Master.

I’ve attempted to add ldaps:// to the server address and tried to switch ports to 636 but I always end up with configuration incorrect in the NextCloud LDAP settings.

I have other services bound securely to the ODM so I don’t think the issue is there, could anyone else using a similar setup share their experience?

Thanks in advance