SERVICENOW-CIS-DISCOVERY CMDB Integration And Maintenance — 40 Questions

Question 1

You are troubleshooting a scenario where Discovery is creating duplicate CIs for the same server. Which table should you inspect to verify the Identification Rule settings for the specific CI class?

Accepted Answer

cmdb_identifier_entry. The cmdb_identifier_entry table defines the attributes used to uniquely identify a CI, which prevents duplicates.

Answer

discovery_device_history

Answer

sys_reconciliation_rule

Answer

cmdb_ci_relation

Question 2

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.. The IRE uses source priority and data source configuration to manage conflicting attribute data.

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 3

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. Troubleshooting involves verifying the pattern execution, the identification rule logic, and the reconciliation rule settings.

Answer

Increase the Discovery timeout value

Answer

Modify the MID Server cluster configuration

Question 4

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. Discovery Source and reconciliation rules define which data sources are allowed to update specific attributes, preventing lower-priority sources from overwriting authoritative ones.

Answer

CMDB Health Dashboard

Answer

Discovery Pattern Pre/Post scripts

Answer

MID Server Capabilities

Question 5

During a Discovery run, a Linux server is identified, but the CMDB record is not updated with the latest memory information. Which log should be inspected to troubleshoot the Identification and Reconciliation engine (IRE) process?

Accepted Answer

System Logs > Identification and Reconciliation Engine Logs. The IRE logs all interactions between Discovery and the CMDB, including validation failures and attribute update denials.

Answer

System Logs > Node Logs

Answer

Discovery > Pattern Logs

Answer

System Logs > Discovery Logs

Question 6

A Discovery scan successfully identifies a Linux server, but the 'Operating System' field is not being updated in the CMDB. You have verified that the pattern correctly extracts the OS version. What is the most likely configuration issue?

Accepted Answer

A Reconciliation Rule exists that prevents the 'ServiceNow' data source from updating the 'Operating System' attribute.. Data source reconciliation rules determine which data sources have update authority for specific fields.

Answer

The CI class is marked as 'Read Only' in the CMDB dashboard.

Answer

The Discovery schedule is using the wrong MID server.

Answer

The Linux pattern is not published to the production environment.

Question 7

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 8

You notice that Discovery is creating duplicate CIs for Windows servers. Which CMDB feature should you investigate first to ensure Discovery correctly identifies existing CIs?

Accepted Answer

Identification Rules. The Identification and Reconciliation Engine (IRE) uses identification rules to prevent duplicates by matching incoming data against existing CIs based on defined criteria.

Answer

Discovery Schedules

Answer

Transform Maps

Answer

Data Preserver

Question 9

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.. CMDB Health settings must be configured to include specific classes for health metrics calculation.

Answer

Create an ACL for the CMDB Health table.

Answer

Restart the Discovery services.

Answer

Run a full Discovery of the entire environment.

Question 10

When reviewing the CMDB Health Dashboard, you notice a high 'Staleness' score for several Windows servers. What is the primary cause of high staleness?

Accepted Answer

The CIs have not been updated by Discovery within the configured staleness threshold.. Staleness is calculated based on the 'sys_updated_on' field compared to the threshold defined in the CMDB Health properties.

Answer

The CIs are not being reconciled correctly.

Answer

The Discovery credentials failed during the last scan.

Answer

The CIs have invalid relationship types.

Question 11

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 12

Which tool provides a visual representation of how different data sources are contributing to the current state of a CI record?

Accepted Answer

CI Timeline. The CI Timeline or the 'CMDB Data Manager' visual tools allow viewing update history and sources.

Answer

Discovery Log

Answer

CMDB Health Dashboard

Answer

Service Map

Question 13

When using the Identification and Reconciliation Engine (IRE), what happens if a payload contains a CI that matches multiple existing CIs based on the identification rule?

Accepted Answer

The payload is rejected with an error indicating an identification rule non-uniqueness.. IRE provides specific error codes to indicate when an identification rule is not unique, which must be resolved to avoid data corruption.

Answer

The match is ignored, and all attributes are updated in both records.

Answer

The first match found is updated.

Answer

A new CI is created as a duplicate.

Question 14

What is the consequence of having an incorrect 'Identification Rule' for a hardware CI class?

Accepted Answer

Discovery may create duplicate CI records for the same physical hardware.. Incorrect rules lead to either duplicate CI records or 'flapping' (repeatedly updating the wrong CI).

Answer

Discovery will stop scanning the network.

Answer

The CMDB Health Dashboard will automatically fix the rules.

Answer

The MID server will lose its credentials.

Question 15

An administrator wants to ensure that data imported from an external asset system does not overwrite data collected by Discovery. How should this be configured?

Accepted Answer

Configure Reconciliation Rules to grant Discovery higher priority for those attributes.. Reconciliation rules allow you to specify which data sources are authoritative for specific CI attributes.

Answer

Change the CI class to read-only.

Answer

Use an Import Set Transform Map script to check the source.

Answer

Disable the external import integration.

Question 16

A pattern is failing to map a specific attribute because the command used returns multi-line output. What is the standard way to handle this in a Discovery Pattern?

Accepted Answer

Use a 'Parse' step with a Regular Expression (Regex) to extract the specific value.. Patterns use parsing steps (like Regex or Split) to convert multi-line output into structured attribute data.

Answer

Use a MID Server script file to process the output.

Answer

Ignore the attribute.

Answer

Change the command to only return a single line.

Question 17

What is the purpose of a 'Discovery Source' in the CMDB?

Accepted Answer

To identify which tool or process created or updated the CI record.. The 'Discovery Source' field identifies which tool (Discovery, Service Mapping, SCCM, etc.) populated or last updated the CI record.

Answer

To store the last successful login time.

Answer

To specify which MID server is authorized to access the CI.

Answer

To define which credentials should be used for a scan.

Question 18

Which action should you perform before modifying a default Discovery Pattern?

Accepted Answer

Create a copy of the pattern.. To avoid losing changes during upgrades, you must make a copy of the pattern before modification.

Answer

Export the pattern to an XML file.

Answer

Reboot the MID server.

Answer

Delete the original pattern.

Question 19

You are migrating from legacy horizontal discovery to Service Mapping. How should you handle the transition of existing CMDB CI relationships?

Accepted Answer

Ensure existing CIs have stable identification attributes so Service Mapping can build on them.. Service Mapping relies on existing identification rules; existing relationships should be verified for consistency.

Answer

Create a new CMDB class for all Service Mapping CIs.

Answer

Force all CIs to be re-discovered by the same MID server.

Answer

Delete all existing relationships before starting.

Question 20

Which module allows you to visualize the dependencies and connections between CIs in a map view?

Accepted Answer

Dependency View. The Dependency View is the standard ServiceNow interface for visualizing CI relationships.

Answer

CMDB Query Builder

Answer

Discovery Status

Answer

Business Service Map