Generally if GRLoader fails to update a CI, an error or a warning message will be displayed or written in a log. However, when tried to update only Tenant, no error or warning message is displayed as shown below and it looks the CI is updated successfully.
Read Skipped Inserts Updates Errors Warnings CI 2 0 0 2 0 0 Relation 0 0 0 0 0 0
21:54:08.312 GRLoader ended
As stated on the Service Desk Manager CA CMDB r12.9 Technical Reference Guide p.193 - GRLoader and Multi-Tenancy, Tenants can only be assigned during the creation of a CI. So if we would like to change the Tenant after we create the CI, we need to run the command pdm_settenant instead.
It is expected behaviour that the GRLoader does not update the Tenant of the CI. Also, no error or warning message appears if the GRLoader does not update it. This is working by design.