He noted that he's using the Symas OpenLDAP builds for Linux. We >do not offer FreeBSD builds for 2.5 or 2.6. Thus he specifically >chose to use a non-standard path for the builds he's using.
Quanah is correct. I'm on a Ubuntu 20.04 test machine.
I stopped slapd, moved the directory from /var/symas/openldap-data/slapd.d/ over to the standard location of /opt/symas/etc/openldap/slapd.d/ and started slapd again, and that resolved the issue.
I thought I had tried the 'standard' location previously, but I obviously did not -- or if I did, I didn't set it up correctly. I can't remember how or why I found the /var/symas/openldap-data directory, but when I did, I guessed (incorrectly) that this was where it needed to reside. Obviously I was mistaken. I'm learning things every day. Thank you, Quanah.
I intentionally tore down all of my config, and am starting over as of yesterday afternoon to try to build this, from scratch, correctly now.
My issue in this thread is resolved.