Question 1,691 of 1,786
Data Operations and SupporthardMultiple ChoiceObjective-mapped

Quick Answer

The answer is to add a VPC endpoint for S3 and configure the bucket policy to allow access from the Glue job's VPC endpoint. This is correct because when an S3 bucket policy restricts access to a specific VPC, requests must originate from a VPC endpoint; however, AWS Glue jobs running in a VPC do not automatically route S3 traffic through that endpoint—they default to internet-bound traffic unless explicitly configured to use the endpoint. The intermittent success occurs because some requests may coincidentally come from the allowed IP range, but the core issue is that the Glue job’s traffic is not consistently routed through the VPC endpoint. On the AWS Certified Data Engineer Associate DEA-C01 exam, this scenario tests your understanding of how VPC endpoints interact with service-level resource policies, a common trap where candidates confuse IAM permissions with network-based access controls. Remember the key distinction: IAM policies control *who* can act, while bucket policies with VPC conditions control *where* the request comes from. A useful memory tip is “Glue needs a gateway, not just a policy”—the VPC endpoint is the gateway that satisfies the bucket policy’s location requirement.

DEA-C01 Data Operations and Support Practice Question

This DEA-C01 practice question tests your understanding of data operations and support. The scenario asks you to isolate a root cause — eliminate options that address a different problem before choosing. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.

Your company runs a critical data processing pipeline that ingests data from multiple sources into an Amazon S3 bucket. An AWS Glue ETL job processes this data and writes the output to an Amazon Redshift cluster. The pipeline is triggered by an S3 event notification that invokes an AWS Lambda function, which starts the Glue job. Recently, you have observed that the Glue job occasionally fails with an AccessDenied error when trying to access the S3 bucket. The IAM role used by the Glue job has the following policy: { "Version": "2012-10-17", "Statement": [ { "Effect": "Allow", "Action": [ "s3:GetObject", "s3:ListBucket" ], "Resource": [ "arn:aws:s3:::input-bucket", "arn:aws:s3:::input-bucket/*" ] }, { "Effect": "Allow", "Action": [ "redshift:CopyData" ], "Resource": "*" } ] }. The S3 bucket has a bucket policy that allows access only from a specific VPC. The Glue job runs in a VPC with the appropriate VPC endpoints configured. The error occurs intermittently and sometimes retries succeed. What is the most likely cause and correct course of action?

Clue words in this question

Noticing these words before you look at the options changes how you read each choice.

  • Clue: "most likely"

    Why it matters: Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.

Question 1hardmultiple choice
Full question →

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

Add a VPC endpoint for S3 and configure the bucket policy to allow access from the Glue job's VPC endpoint.

Option D is correct because the Glue job runs in a VPC, but if the S3 bucket policy requires requests to come from the VPC endpoint, the Glue job's requests must originate from that endpoint. However, Glue jobs running in a VPC do not automatically route S3 traffic through VPC endpoints; they go through the internet unless a VPC endpoint is explicitly used. The intermittent success might be due to other requests coming from the same IP range. The correct action is to ensure the Glue job uses a VPC endpoint for S3. Option A is wrong because the bucket policy is the issue, not the IAM policy. Option B is wrong because the Lambda function is not directly accessing S3. Option C is wrong because the Glue job already runs in the VPC.

Key principle: NAT direction and interface roles matter as much as the IP address mapping. Inside/outside designation controls which traffic is translated.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

  • Add a VPC endpoint for S3 and configure the bucket policy to allow access from the Glue job's VPC endpoint.

    Why this is correct

    This ensures requests from Glue are routed through the VPC endpoint and comply with the bucket policy.

    Clue confirmation

    The clue word "most likely" in the question point toward this answer.

    Related concept

    Static NAT maps one inside address to one outside address.

  • Ensure the Glue job's VPC configuration includes a NAT gateway to route traffic to S3.

    Why it's wrong here

    A NAT gateway would route traffic through the internet, but the bucket policy requires VPC endpoint access.

  • Change the Lambda function to use a different IAM role with broader S3 permissions.

    Why it's wrong here

    The Lambda function triggers the Glue job; it does not access S3. The error is from the Glue job.

  • Modify the Glue job's IAM role to include s3:PutObject permission for the output bucket.

    Why it's wrong here

    The error is AccessDenied on the input bucket, not output. Also, the bucket policy is the likely cause.

Common exam traps

Common exam trap: NAT rules depend on direction and matching traffic

NAT is not only about the public address. The inside/outside interface roles and the ACL or rule that matches traffic are just as important.

Trap categories for this question

  • Command / output trap

    The error is AccessDenied on the input bucket, not output. Also, the bucket policy is the likely cause.

Detailed technical explanation

How to think about this question

NAT questions usually test address translation, overload/PAT behaviour, static mappings and whether the right traffic is being translated. Read the interface direction and address terms carefully.

KKey Concepts to Remember

  • Static NAT maps one inside address to one outside address.
  • PAT allows many inside hosts to share one public address using ports.
  • Inside local and inside global describe the private and translated addresses.
  • NAT ACLs identify traffic for translation, not always security filtering.

TExam Day Tips

  • Identify inside and outside interfaces first.
  • Check whether the scenario needs static NAT, dynamic NAT or PAT.
  • Do not confuse NAT matching ACLs with normal packet-filtering intent.

Key takeaway

NAT direction and interface roles matter as much as the IP address mapping. Inside/outside designation controls which traffic is translated.

Real-world example

How this comes up in practice

A media company stores terabytes of video archives that are accessed once a year for audit purposes. Moving these objects to a cold storage tier (Azure Archive, S3 Glacier, or Google Nearline) costs a fraction of hot storage. Questions like this test whether you understand storage tiers, access frequency tradeoffs, and retrieval latency requirements.

What to study next

Got this wrong? Here's your next step.

Review the four NAT address types (inside local, inside global, outside local, outside global), PAT port overload, and static vs dynamic NAT use cases. Then practise related DEA-C01 NAT questions on configuration and troubleshooting.

Related practice questions

Related DEA-C01 practice-question pages

Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.

Practice this exam

Start a free DEA-C01 practice session

Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.

FAQ

Questions learners often ask

What does this DEA-C01 question test?

Data Operations and Support — This question tests Data Operations and Support — Static NAT maps one inside address to one outside address..

What is the correct answer to this question?

The correct answer is: Add a VPC endpoint for S3 and configure the bucket policy to allow access from the Glue job's VPC endpoint. — Option D is correct because the Glue job runs in a VPC, but if the S3 bucket policy requires requests to come from the VPC endpoint, the Glue job's requests must originate from that endpoint. However, Glue jobs running in a VPC do not automatically route S3 traffic through VPC endpoints; they go through the internet unless a VPC endpoint is explicitly used. The intermittent success might be due to other requests coming from the same IP range. The correct action is to ensure the Glue job uses a VPC endpoint for S3. Option A is wrong because the bucket policy is the issue, not the IAM policy. Option B is wrong because the Lambda function is not directly accessing S3. Option C is wrong because the Glue job already runs in the VPC.

What should I do if I get this DEA-C01 question wrong?

Review the four NAT address types (inside local, inside global, outside local, outside global), PAT port overload, and static vs dynamic NAT use cases. Then practise related DEA-C01 NAT questions on configuration and troubleshooting.

Are there clue words in this question I should notice?

Yes — watch for: "most likely". Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.

What is the key concept behind this question?

Static NAT maps one inside address to one outside address.

About these practice questions

Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →

How Courseiva writes practice questions · Editorial policy

Last reviewed: Jun 20, 2026

Question Discussion

Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.

Loading comments…

Sign in to join the discussion.

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.