SERVICENOW-CIS-DISCOVERY CMDB Integration And Maintenance — 50 Questions

Question 1

When configuring Data Sources for CMDB reconciliation, which TWO of the following are true regarding the behavior of the Identification and Reconciliation Engine (IRE)?

Accepted Answer

Data source importance determines which source takes precedence during a reconciliation conflict.. Option A is correct because the Identification and Reconciliation Engine uses data source importance (a priority ranking configured per data source, e.g., via the Data Source precedence settings) to decide which source's value wins when two sources provide conflicting values for the same CI attribute during reconciliation. Option E is correct because IRE supports Reconciliation Rules that specify, per data source and CI class, which attributes that source is authoritative for and allowed to update, preventing lower-trust sources from overwriting trusted values. Option B is incorrect because custom data sources do not require a brand-new Identification Rule for every CI class; identification rules are defined per CI class and can be reused across data sources, and custom sources can leverage existing rules. Option C is incorrect because IRE does not simply ignore undefined data sources; data sources are configured and associated with identification/reconciliation rules, and the engine processes data according to those rules rather than discarding sources merely for lacking an explicit definition. Option D is incorrect because Discovery does not automatically outrank manual CMDB updates by default; precedence is governed by the configured data source importance values, and manual/other sources can be ranked above or below Discovery depending on that configuration.

Answer

Custom data sources require a new Identification Rule for every CI class.

Answer

IRE ignores data sources that are not explicitly defined in the Identification Rules.

Answer

Discovery always has higher priority than manual CMDB updates by default.

Question 2

Which THREE actions should you take when troubleshooting a discovery process that is failing to populate the 'Serial Number' field for a specific class of routers?

Accepted Answer

Review the Identification Rule for the router class. Option B is correct because the Identification Rule determines which attributes (including serial number) are used to uniquely identify and match a router to its class, so a misconfigured or missing serial number entry there will prevent the field from being populated. Option C is correct because the Reconciliation Rule defines which data source and attribute value wins when multiple sources report the serial number, so an incorrect precedence or exclusion will leave the field empty. Option D is correct because the Pattern Designer produces the parsed variable for serial number from the device's output (e.g., via SNMP OID or CLI command); if the pattern's serial number variable is misnamed, unmapped, or not extracted, discovery cannot populate the field. Option A is not correct because a timeout affects whether discovery completes at all, not the extraction of a specific attribute like serial number. Option E is not correct because MID Server cluster configuration affects load distribution and failover, not the parsing or mapping of the serial number attribute.

Answer

Increase the Discovery timeout value

Answer

Modify the MID Server cluster configuration

Question 3

During a Discovery run, a Linux server CI is updated with a null value for its serial number, overwriting a manually entered value. Which configuration prevents this?

Accepted Answer

Reconciliation Rules. Reconciliation Rules in ServiceNow CMDB determine which data source wins when multiple sources update the same CI attribute. By default, Discovery is treated as a higher-precedence source than manual entry for most attributes, so a null serial number from Discovery can overwrite a manually entered value. Configuring a reconciliation rule that prioritizes manual updates (or ignores null values) prevents the overwrite.

Answer

CMDB Health Dashboard

Answer

Discovery Pattern Pre/Post scripts

Answer

MID Server Capabilities

Question 4

A Discovery administrator needs to ensure that only specific CI classes are populated by Discovery. Where should this configuration be managed to prevent unauthorized CI creation?

Accepted Answer

Identification and Reconciliation > Identification Rules. The Discovery CI classification process uses Identification and Reconciliation rules to determine how CIs are created and updated in the CMDB.

Answer

Discovery > Properties

Answer

Discovery Definition > CI Classifications

Answer

CMDB Health > Dashboard

Question 5

You have a custom CI class that is not appearing in the CMDB Health Dashboard reports. What is the first step to ensure it is included?

Accepted Answer

Add the class to the CMDB Health Dashboard 'Dashboard Configuration' settings.. To include a custom CI class in CMDB Health Dashboard reports, the class must be added to the Dashboard Configuration settings. This ensures that the health metrics and reports include the custom class.

Answer

Create an ACL for the CMDB Health table.

Answer

Restart the Discovery services.

Answer

Run a full Discovery of the entire environment.

Question 6

Which Discovery feature allows you to automatically create relationships between newly discovered CIs and existing business applications?

Accepted Answer

Service Mapping. Discovery post-processing scripts or Pattern-based 'Relationship' steps are used to map CIs to business applications.

Answer

Discovery Home

Answer

CMDB Health Dashboard

Answer

Identification and Reconciliation Engine (IRE)

Question 7

You notice that the 'Last Discovered' field is not updating, even though the Discovery schedule runs successfully. What is the first thing you should check?

Accepted Answer

Check the Identification and Reconciliation Engine (IRE) logs.. The 'Last Discovered' field is updated by the Discovery process; if it isn't updating, the process may be failing at the Identification stage.

Answer

Check the MID server's CPU usage.

Answer

Update the Discovery Pattern definition.

Answer

Verify the network connectivity to the targets.

Question 8

You have a situation where a CI is being updated, but you don't know which data source is responsible. Where can you look to find the authoritative source for each attribute?

Accepted Answer

CMDB Reconciliation Rules. Reconciliation rules allow an administrator to define which sources are permitted to update specific CI attributes.

Answer

CI relationship graph

Answer

Discovery schedule settings

Answer

Discovery log

Question 9

Which THREE of the following are valid ways to improve the 'Correctness' metric in the CMDB Health Dashboard?

Accepted Answer

Refining identification rules to prevent duplicate CI creation.. Option A is correct because refining identification rules (e.g., IRE identification and reconciliation engine criteria) prevents duplicate CIs from being created in the first place, directly improving the Correctness metric which penalizes duplicate CIs. Option B is correct because deleting or merging duplicate CI records removes existing duplicates, which is exactly what the Correctness metric measures and rewards. Option E is correct because implementing reconciliation rules ensures a single authoritative source of truth for each CI, resolving conflicting data from multiple discovery sources and thus improving correctness. Option C is not correct because running more frequent discovery scans only affects data freshness/completeness, not the correctness of CI records. Option D is not correct because adding more fields to CI classes increases data capture but does not by itself improve the correctness of existing CI data.

Answer

Running more frequent discovery scans.

Answer

Adding more fields to the CI classes.

Question 10

Which THREE of the following items are considered 'CI Identification' best practices?

Accepted Answer

Keep identification rules as simple as possible to maximize performance.. Option A is correct because keeping CI identification rules as simple as possible reduces processing overhead and avoids complex, error-prone matching logic that degrades discovery and reconciliation performance. Option C is correct because attributes populated by multiple data sources (such as serial number, MAC address, or asset tag) provide corroboration and higher confidence when matching and de-duplicating CIs across discovery sources. Option D is correct because stable, immutable attributes like hardware serial numbers do not change over the CI's lifecycle, making them reliable unique identifiers for hardware CIs. Option B is not a best practice because creating a unique rule for every single CI instance is unmanageable and defeats the purpose of scalable, reusable identification rules. Option E is not a best practice because the 'Name' field is typically user-editable and non-unique, so it cannot reliably serve as a primary unique identifier.

Answer

Create a unique identification rule for every single CI instance.

Answer

Use the CI's 'Name' field as the primary unique identifier.

Question 11

Which THREE of the following are valid CMDB Health metrics?

Accepted Answer

Completeness. The CMDB Health Dashboard specifically tracks Completeness, Correctness, and Compliance (often interpreted as Relationships/Staleness).

Answer

Performance

Answer

Availability

Question 12

When a discovery pattern finishes, which log should you review to see the raw payload output that was sent to the IRE?

Accepted Answer

Discovery Log. The 'Discovery Log' within the Discovery Status record shows the sequence of events, and the 'Payload' tab or related list shows what was sent to the IRE.

Answer

MID Server log

Answer

CMDB Health Dashboard

Answer

System Log

Question 13

You need to ensure that a specific attribute is NOT updated by any source except a manual update from a specific user group. How can this be done?

Accepted Answer

Set the Reconciliation rule for that attribute to only allow the 'Manual' data source.. To ensure a specific attribute is not updated by any source except manual updates from a specific user group, you set the Reconciliation rule for that attribute to only allow the 'Manual' data source. This makes the attribute authoritative only when updated manually, preventing automated sources from overwriting it.

Answer

Change the class to 'Internal'.

Answer

Remove the attribute from the discovery pattern.

Answer

Create a business rule that runs after insert/update.

Question 14

You are troubleshooting a scenario where Discovery is creating a new CI instead of updating an existing one. You have verified the serial number is correctly identified. What is the most likely cause within the Identification Rule?

Accepted Answer

The 'Required' checkbox is unchecked for the Serial Number attribute in the Identifier Entry.. If the identification rule has 'Required' fields that do not match the incoming payload, the IRE cannot successfully match the existing CI.

Answer

The CI Class is not in the Discovery Schedule.

Answer

The 'Sync' flag is disabled in the Discovery Schedule.

Answer

The Discovery Pattern is set to 'Create' mode.

Question 15

You need to ensure that Discovery data from a third-party integration does not overwrite manual updates made by the IT team in the CMDB. Which feature should you configure?

Accepted Answer

Reconciliation Rules. Reconciliation Rules define which data sources are allowed to update specific attributes of a CI.

Answer

CMDB Transform Maps

Answer

Discovery Access Control Lists (ACLs)

Answer

Data Preserver

Question 16

During Discovery, a switch is identified, but its related interfaces are not appearing in the CMDB. What is the first thing you should check?

Accepted Answer

Identification Rule for the interface class. When a switch is discovered but its interfaces do not appear in the CMDB, the most likely cause is that the interface CI class has no Identification Rule (or a misconfigured one), so Discovery cannot create or reconcile the interface CIs. Identification Rules define the unique key (e.g., name + switch sys_id) used to match discovered interface data to existing CI records, and without one, interfaces are dropped or duplicated.

Answer

MID Server capacity

Answer

Discovery Schedule timing

Answer

Discovery Error Log

Question 17

You are tasked with ensuring that Discovery only populates the 'Short Description' field on a CI if it is currently empty. Which IRE feature allows for this conditional update?

Accepted Answer

IRE Data Source Rules with 'Skip if not empty' logic. The 'Apply to' and conditional logic in the IRE or Data Source rules allows for fine-grained control over attribute updates.

Answer

Business Rule on the CI table

Answer

Discovery Pattern Step: 'Update only if empty'

Answer

Reconciliation Rule Priority

Question 18

A complex environment requires that two different Discovery sources (e.g., ServiceWatch and a third-party tool) populate the same CI attributes. How can you ensure the third-party tool's data is preferred over Discovery for specific attributes?

Accepted Answer

Set the third-party data source priority to 100 and discovery to 200.. Reconciliation Rules assign a priority value to data sources; the highest priority source wins the attribute update.

Answer

Disable 'Discovery' in the CI Class identification rule.

Answer

Use a Business Rule to intercept the discovery payload.

Answer

Set the discovery source priority to 100 and the third-party source to 200.

Question 19

Which TWO actions should you perform to maintain the integrity of the CMDB when a CI is decommissioned?

Accepted Answer

Update the 'Operational status' field to 'Retired'.. To properly retire a CI, you must update its status and ensure it no longer appears in active discovery processes.

Answer

Delete the CI record from the database.

Answer

Clear the 'Last discovered' field.

Answer

Change the CI class to 'Archive'.

Question 20

Which TWO issues might be discovered in the 'Correctness' category of the CMDB Health Dashboard?

Accepted Answer

Duplicate CIs. Correctness metrics specifically identify duplicates and orphaned CIs that threaten CMDB data integrity.

Answer

Stale CIs

Answer

Expired credentials

Answer

Missing critical attributes