Discovery identifiers When Discovery finds a device in your network, it makes an effort to determine if the device already exists in the CMDB. When Discovery is configured to use identifiers, it launches special identity probes that accumulate identification data for each device and feed that data into the identifiers, which determine the action that Discovery must take for each device. Identifiers accurately determine the identity of the device to prevent the creation of duplicate CIs. The identifiers determine how to proceed for each device discovered, based on the result state. The identifiers pass the result state for a discovered device back to the identity sensors, which respond appropriately, either by launching additional exploratory probes to continue discovering the device or by taking no further action on the device. Control how identification processes duplicate CIs You can control how Discovery handles duplicates using properties installed with Identification and Reconciliation. Use the glide.identification_engine.skip_duplicates and glide.identification_engine.skip_duplicates.threshold properties. All new instances use identifiers from the CMDB Identification and Reconciliation framework. Upgrades to Geneva still preserve the legacy identifiers, but you can switch to the new identifiers using a property: glide.discovery.use_cmdb_identifiers. You must manually add this property to the System Properties [sys_properties] table and set it to true to use the new identifiers. To preserve functionality in custom legacy identifiers, convert them to the new CMDB identifier rules format before enabling this property. The system does not reconfigure your custom identifiers to the new framework automatically.Note: When Service Mapping is active, the new identifiers from the CMDB Identification and Reconciliation framework are always used regardless of the property value. How Discovery identifiers workWhen Discovery has determined the device's class, it launches an identity probe that is configured to run one or more commands with a single authentication. Discovery CMDB identifiersThe CMDB identifiers provide a single point of entry for inserting and updating CIs in the CMDB that ensures data integrity.Evaluation order for Discovery identifiersCustom identifiers must have different Order values than those of the default identifiers. Enable Discovery identifiersIdentifiers are used for all Discovery schedules that are set up to discover Configuration items.Configure Discovery to use CMDB identifiersA system property allows you to configure your instance to use CMDB identifier exclusively.Custom Discovery identifiers and identity probesIn addition to default ServiceNow identity probes and identifiers, you can create your own probe/sensor pairs and matching identifiers when needed.List of Discovery multi-probesThe following identity multi-probes are bundled with Discovery. The corresponding multi-sensors have the same names.Configure Discovery identity sensorsYou must have a properly configured multi-sensor for each identity probe in your system. This topic explains how to configure Discovery identity sensors.Discovery device classificationWhen a classification probe runs, it returns the device class and operating system, if the device is a computer.Serial number types for discovered devicesSerial number types in the Serial Number [cmdb_serial_number] table vary depending on the CI, as described in the following examples.Legacy Discovery identifiersThe following legacy identifiers are included in the ServiceNow base system.