What table links tasks to CIs?

task_ci — a many-to-many join between task and cmdb_ci enabling 'affected CIs' on incidents, problems, and changes.

What is change collision detection?

A pre-approval check that flags overlapping change windows on the same or related CIs, using cmdb_rel_ci traversal.

How does an incident affect service availability?

When cmdb_ci.operational_status flips to Non-Operational, an outage record (cmdb_ci_outage) is opened and rolls up impact through Depends on relationships.

What is the difference between Business Service and Configuration Item on an incident?

Business Service is the consumer-facing service impacted; CI is the specific asset the incident is about. Both can be set, and BSM uses the CI's relationships to derive the service.

A DB restart change was approved but broke a business service nobody flagged. How do you prevent it?

Enable change collision + service impact — CAB workflow uses cmdb_rel_ci to walk from the DB up to affected services. Make Business Services required on high-risk change categories. Add automated blackout checks against cmdb_ci_service.change_freeze windows. Alternate: Alternate: bolt on Predictive Intelligence 'similar changes' to surface historical incidents linked to the same CI class. Pitfall: Approving DB changes without walking the dependency tree — impact only appears at cutover.

Discovery Interview · Hub

DISCOVERY &
CMDB DEEP DIVE.

14 focused sub-modules — each with curated definitive Q&A, scenario drills, and a one-click AI expander so you can grow the list toward 100+ questions per section as you study.

01
CMDB
How the Configuration Management Database is structured, extended, and governed.
02
Discovery
How ServiceNow Discovery finds infrastructure and populates the CMDB.
03
MID Servers
The Java-based agent that brokers Discovery and integrations.
04
IRE
The single entry point for every CI write.
05
CIs
What a CI is, what attributes matter, and how CIs are keyed.
06
CI Classes & Tables
How class hierarchy, table extension, and table-per-hierarchy work.
07
Relationships & Dependencies
How CIs relate and how impact propagates.
08
Service Mapping
Mapping business services from entry points down.
09
Integrations & Imports
Getting CI data in from external systems.
10
CI Lifecycle
Onboarding, updating, and retiring CIs by policy.
11
CMDB Health
Measuring completeness, correctness, and compliance.
12
ITSM Integration
How the CMDB powers impact, CAB, and RCA.
13
CSDM
The prescriptive blueprint for CMDB modeling.
14
HAM & SAM
Asset lifecycle, contracts, entitlements, and reclamation.

Also useful

Discovery starter guide CMDB + CSDM basics Scenario scripting

CMDB

Discovery

MID Servers

IRE

CIs

CI Classes & Tables

Relationships & Dependencies

Service Mapping

Integrations & Imports

CI Lifecycle

CMDB Health

ITSM Integration

CSDM

HAM & SAM

Also useful