Custom IRE data sources do not appear in Identification SimulationIssue Resolve custom data sources not appearing in the Identification Simulation dropdown when troubleshooting Identification and Reconciliation Engine (IRE) payload processing. Custom IRE data sources must be registered as discovery source choices to become available within the Identification Simulation interface. Symptoms A custom IRE data source value does not appear in the Identification Simulation dropdown list, even though the data source is configured and used in your IntegrationHub ETL implementationWhen attempting to select a custom data source for simulation testing, only default discovery source values are availableSimulation testing cannot be performed for your custom ETL integration Facts The Identification Simulation tool lists only discovery source values that are configured as valid choices for the cmdb_ci.discovery_source fieldCustom IRE data sources are created during ETL implementation to identify the source feed of imported configuration itemsFor a custom data source to be available within Identification Simulation, it must first exist as a choice value in the cmdb_ci.discovery_source choice listIdentification Simulation is used to test and validate Identification Rules before running live ETL processing Release All supported versions of ServiceNow with Service Graph Connectors enabled. Custom data source registration follows the same process across releases. Cause When a custom IRE data source is configured in your Robust Transform or ETL integration, it must be registered as a valid choice for the CMDB discovery source field. If this choice value does not exist in the cmdb_ci.discovery_source choice list, the Identification Simulation tool cannot display it as a selectable option, preventing simulation testing of your custom ETL implementation. Resolution Navigate to the discovery source choice list. Go to System Definition > Dictionaries. Requires the admin or system_definition_admin role.Search for the cmdb_ci.discovery_source field. In the Dictionaries list, search for or filter by: cmdb_ci.discovery_source Select the name link to open the field definition.Open the choice list for this field. In the field definition, locate the Choices section. Select the name link or the list icon to open the choice list for cmdb_ci.discovery_source.Verify your custom data source value is present in the choice list. Review the list of available discovery source choices. Confirm whether your custom IRE data source value (for example, the value you use in your Robust Transform configuration such as "Custom ETL Feed" or "Manual Import ETL") is already listed. If your custom value exists in the choice list, proceed to Step 7. If it is missing, proceed to Step 5.Add your custom data source value as a new choice. Select the New button to create a new choice entry. Requires the admin or system_definition_admin role.Populate the choice fields for your custom data source. Label: Enter the display name for your custom data source (for example, "Custom ETL Feed" or "Manual CI Load")Value: Enter the exact value you use in your Robust Transform configuration as the IRE Data Source (this value must match exactly what is configured in your transform)Description (optional): Enter a description identifying the ETL integration or data source purpose (for example, "Custom CMDB As A Service data source for manual CI load") Select the Submit button to save the new choice.Verify the custom data source now appears in Identification Simulation. Go to Service Graph Connectors > Administration > Identification Simulation. Requires the integrations_admin or admin role. In the Identification Simulation interface, locate the dropdown for selecting a data source. Your custom data source value should now be available for selection. Select it and test your IRE configuration with your sample payloads. Related Links IRE (Identification and Reconciliation Engine) troubleshooting and payload analysis — Provides detailed guidance on capturing IRE input and output payloads, enabling diagnostic logging, and interpreting IRE processing behavior when custom data sources are in use.