A developer in Account A has an Amazon S3 bucket that contains sensitive data. The developer wants to grant an IAM user in Account B read-only access to objects in the bucket. The developer has added a bucket policy in Account A that grants s3:GetObject access to the IAM user's ARN. However, the IAM user in Account B still receives Access Denied errors. What additional configuration is required?
Answer choices
Why each option matters
Good practice is not just finding the correct option. The wrong answers often show the exact trap the exam wants you to fall into.
Best answer
Add an IAM policy in Account B that allows the user to perform s3:GetObject on the bucket's ARN.
The IAM user must have explicit permission via an IAM policy to access the S3 bucket. The bucket policy alone is not sufficient; the user's account must also allow the action.
Distractor review
Create an S3 access point and grant the user access through it.
S3 access points are not required for this scenario. They provide a simplified way to manage access but would not resolve the missing IAM policy issue.
Distractor review
Change the bucket policy to grant access to the entire AWS account B instead of the specific user.
Granting access to the entire account could violate least privilege and still does not address the need for the user to have an IAM policy allowing the action.
Distractor review
Enable S3 object ownership and set the bucket ACL to grant read access to the user in Account B.
S3 ACLs are legacy and not recommended. They also require the object owner to grant access, and the bucket policy is already in place. The missing piece is the IAM policy in the user's account.
Common exam trap
Common exam trap: ACLs stop at the first match
ACLs are processed top to bottom. The first matching entry wins, and an implicit deny usually exists at the end.
Technical deep dive
How to think about this question
ACL questions test precision: source, destination, protocol, port and direction. A generally correct ACL can still fail if it is applied on the wrong interface or in the wrong direction.
KKey Concepts to Remember
- Standard ACLs match source addresses.
- Extended ACLs can match source, destination, protocol and ports.
- The first matching ACL entry is used.
- There is usually an implicit deny at the end.
TExam Day Tips
- Check inbound versus outbound direction.
- Read the ACL from top to bottom.
- Look for a broader permit or deny above the intended line.
Related practice questions
Related DVA-C02 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
More questions from this exam
Keep practising from the same exam bank, or move into a focused topic page if this question exposed a weak area.
Question 1
A developer is building a REST API using Amazon API Gateway that will serve static content from an Amazon S3 bucket. The API should cache responses for frequently accessed objects to reduce latency. Which API Gateway feature should the developer enable?
Question 2
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Question 3
A developer has an AWS Lambda function that processes messages from an Amazon SQS standard queue. The function is idempotent and currently has a batch size of 10. The developer wants to increase throughput and increases the batch size to 100. After the change, CloudWatch metrics show a significant increase in throttles and the queue backlog is growing. The function's reserved concurrency is set to 10. What is the most effective action to resolve the throttling and improve throughput?
Question 4
A developer is managing an application running on Amazon EC2 instances behind an Application Load Balancer. Users report that the application becomes unresponsive after several hours, and restarting the instance temporarily fixes the issue. The developer suspects a memory leak but cannot add custom instrumentation. Which AWS service can collect memory utilization metrics and help identify the memory leak with minimal configuration?
Question 5
A developer is building a serverless web application using AWS Lambda and Amazon DynamoDB. The application needs to perform complex aggregations on data stored in DynamoDB. Which AWS service should the developer use to perform these aggregations efficiently without reading all the data into Lambda?
Question 6
A developer has an Amazon S3 bucket containing private user documents. The application must generate a time-limited URL for users to download their own documents without requiring the users to have AWS credentials. Which solution should the developer use?
FAQ
Questions learners often ask
What does this DVA-C02 question test?
Standard ACLs match source addresses.
What is the correct answer to this question?
The correct answer is: Add an IAM policy in Account B that allows the user to perform s3:GetObject on the bucket's ARN. — For cross-account S3 access, both a bucket policy (in the account owning the bucket) and an IAM policy (in the account of the user) are required. The bucket policy grants access to the user, but the user must also have an IAM policy that allows s3:GetObject to be effective. The user cannot assume a role here because the bucket policy directly references the user ARN.
What should I do if I get this DVA-C02 question wrong?
Then try more questions from the same exam bank and focus on understanding why the wrong options are tempting.
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