For migrations between minor or major releases, 2.3->2.4
for example) that would be the correct procedure. For point
releases it is almost never necessary. Exceptions being:
1) for BDB based backends, if the BDB major or minor version
that OpenLDAP is linked to is different
2) early releases of slapd-mdb and current slapd-mdb, as
there was an unavoidable db format change. I forget exactly when
but I believe somewhere on the 2.4.2x releases.
Outside of that, a full reload is generally pointless,
although it can reclaim unused space in the DB created by object
Anytime I upgrade to new version I export the
database using slapcat, and after upgrading re-import the
data. If I am not wrong that is the recommended practice (http://www.openldap.org/doc/admin24/maintenance.html
University of Lethbridge, AB.