CIS-DF Ingest Practice Question
An organization discovers network gear using both SNMP Discovery and an external cloud management platform API. Both integrations populate the same physical switch CIs. The cloud platform sometimes sends an empty string for the serial number, which accidentally clears out valid serial numbers previously populated by SNMP Discovery. How can this be prevented using CMDB ingestion controls?
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Configure IRE payload settings or Data Source Precedence rules to ignore empty or null attribute updates from specific data sources.
The IRE supports ignore empty attributes or data source precedence settings that prevent empty or null values from overwriting existing non-empty data.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Delete the identification rule for serial number.
Why it's wrong here
Deleting the identification rule would break CI matching entirely, causing duplicate records.
- ✗
Write an Inbound Email Action to reject empty payloads.
Why it's wrong here
Inbound email actions handle email notifications and inbound tickets, not API/Discovery JSON payloads.
- ✗
Set the serial number field dictionary attribute to 'read-only'.
Why it's wrong here
Making a field read-only in the dictionary prevents all updates, including valid ones from authoritative sources.
- ✓
Configure IRE payload settings or Data Source Precedence rules to ignore empty or null attribute updates from specific data sources.
Why this is correct
Configuring the IRE to ignore empty attribute values prevents lower-priority or incomplete payloads from blanking out existing valid data.
About these practice questions
Courseiva writes every CIS-DF question from scratch — 320 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed August 2026 · checked against the official ServiceNow exam blueprint
This CIS-DF practice question is part of Courseiva's free ServiceNow certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the CIS-DF exam.