DEA-C01 Data Ingestion and Transformation Practice Question
A company uses Amazon Kinesis Data Firehose to deliver data to Amazon S3. The data is compressed with GZIP and partitioned by year, month, day, and hour. The delivery stream is configured to buffer up to 5 MB or 60 seconds. Some records are missing from S3. What is the most likely cause?
⚠ Common exam trap
It's easy for candidates to assume buffering settings (5 MB or 60 seconds) guarantee delivery, but they overlook that Lambda transformation failures can silently drop records without explicit error logging unless CloudWatch monitoring is set up.
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
✓
The Lambda transformation function timed out and records were skipped
When a Lambda transformation function times out, Kinesis Data Firehose will skip the affected records by default. The delivery stream configuration (5 MB or 60 seconds) only controls buffering, not Lambda invocation failures. If the Lambda function exceeds its timeout limit, Firehose treats the invocation as failed and, depending on the error handling configuration, may drop the records entirely, leading to missing data in S3.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
The S3 bucket does not have sufficient permissions
Why it's wrong here
Permission errors would be reported in Firehose monitoring.
- ✗
The data compression format is incompatible with S3
Why it's wrong here
GZIP is a supported compression format for Firehose.
- ✓
The Lambda transformation function timed out and records were skipped
Why this is correct
Firehose drops records if the transformation Lambda exceeds the timeout.
- ✗
The partition key configuration is incorrect
Why it's wrong here
Incorrect partitioning causes files to be in wrong prefixes, not missing.
Quick reference
AWS S3 Storage Class Comparison
| Storage Class | Min Duration | Retrieval | Use Case |
|---|---|---|---|
| S3 Standard | None | Immediate | Frequently accessed data |
| S3 Standard-IA | 30 days | Immediate | Infrequent access, rapid retrieval |
| S3 One Zone-IA | 30 days | Immediate | Non-critical infrequent data |
| S3 Intelligent-Tiering | None | Immediate–hours | Unknown or changing access patterns |
| S3 Glacier Instant | 90 days | Milliseconds | Archive with instant retrieval |
| S3 Glacier Flexible | 90 days | Minutes–hours | Archive, flexible retrieval |
| S3 Glacier Deep Archive | 180 days | Hours | Long-term compliance archive |
Go deeper
Related to this question
About these practice questions
This DEA-C01 question is part of Courseiva's 1,711-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This DEA-C01 practice question is part of Courseiva's free Amazon Web Services 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 DEA-C01 exam.