Where did the "Unknown" CI in the CMDB come from, and why?Issue Have you noticed a new CI named "Unknown" in the CMDB?ReleaseNew York and later.CauseThe record is:http://<instancename>.service-now.com/cmdb_ci.do?sys_id=8fbc3c053bc07300b924874064efc4ae The short description of the record states:"This CI is referenced by all duplicate CIs that were upgraded to New York. Before upgrade, discovery_source for these CIs was set to 'Duplicate'. After upgrade, these CIs are updated to have the new Duplicate Of attribute. However, since the primary CI for these upgraded duplicate CIs is unknown, Duplicate Of references the CI 'Unknown'."ResolutionAs the short description explains, this is an OOTB record related to the new way Duplicate CIs are tracked. This is an enhancement to prevent data loss in the 'Discovery Source' field, which had previously been re-used for this second function. That field is back to being only for data source names for imports/updates of CIs again. Duplicate tracking now has it's own "Duplicate of" field, which needs a reference value to the primary/original CI, and this 'unknown' placeholder record is used when the real primary CI is not known. This is great because you can instantly see what this record is a duplicate of (from the point of view of the Identification rules!) and not have to go searching through health results and de-duplication tasks to find out. This "Unknown" record should not be deleted, even if you have resolved all your duplicate CIs, as the sys_id of the record is hard-coded and expected to be there by CMDB code.More details can be read in the New York release note for CMDB, and the updated CMDB Health/Identification Duplicate CIs page:KB0775380 - Configuration Management Database (CMDB) release notesKB0761542 - Duplicate CIs If you find your users using this CI, perhaps for a change or problem task, when they don't know which CI they should be using, then you could add a Reference Qualifier to the field so that this record is not listed for them for that field.Related LinksKB0794127 Can't delete a CMDB CI record: Delete of XXX not allowed because of a reference in record XXX within the Configuration Item file