OpenLDAP 2.3.27 We have a mesh of servers replicating (with SyncRepl) to each other; they master their own bit of the tree and slave everyone else's, making it hard at times to pick the culprit in case of problems (but I'm stuck with it). Anyway, I've started seeing these weird errors in the logs, just after start-up: is_entry_objectclass("", "2.16.840.1.113730.3.2.6") no objectClass attribute is_entry_objectclass("", "2.5.17.0") no objectClass attribute is_entry_objectclass("", "2.5.6.1") no objectClass attribute Now, I know what the message means, and I know those OIDs are basically internal, but given the DN is null how do I go looking for the problem?