Migrating from slapd 2.3 to 2.4

[Bobby Krupczak <rdk@krupczak.org>]

Hi!

I'm finally updating my file/ldap server and am struggling with
converting my 2.3 slapd.conf file to 2.4 ldif format.

My plan to upgrade was:

 - dump my old ldap db to a single ldif file
 - convert slapd.conf using slaptest
 - connect to slapd using an ldap browser and import my
   old db via the ldif file I created

Is this an appropriate approach that will work?  Am I missing
something?

I ran the slaptest program on my old slapd.conf file and generated a
slew of configs under slapd.d.

However, I'm now running into an error when I try to start slapd.

slapd[4320]: config error processing cn={1}core,cn=schema,cn=config:
olcAttributeTypes: Duplicate attributeType: "2.5.4.2"
slaptest: bad configuration file!
systemd[1]: PID file /var/run/slapd.pid not readable (yet?) after start.

I saw via google where the attribute is duplicated but I never could
find how to edit/modify the configs to remove the duplicate entry.

Any ideas how to remove this duplicate entry? 

Thanks,

Bobby