OpenLDAP XMA can run delta imports using a timestamp attribute you define or the changelog.
The MA uses the attribute specified in “deltaAttribute” custom parameter in order to implement watermarks and detect object changes. You may experience a couple of issues using a delta attribute:
If you find like me that the LDAP implementation you are connecting to does not use a timestamp attribute across all objects, your other option to use deltas is using changelog. In this case, what you have to do is leave “deltaAttribute” custom parameter blank, so the XMA will use changelog. If the account you are using in the XMA to access the LDAP is not administrative, you may need to adjust the permissions in cn=changelog to allow the XMA to work, adjusting the ACI to allow your MA account to read, compare and search all attributes for objects under cn=changelog.