A developer is building a multi-region application using Amazon DynamoDB global tables. The application needs to read data from a replica table in a different region shortly after a write in the primary region. The developer notices that reads sometimes return stale data. Which of the following explains this behavior?
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
Global tables use asynchronous replication, introducing unavoidable replication lag.
Replication between regions is eventually consistent, meaning there can be a delay before data appears in other regions.
Distractor review
The developer must use DynamoDB Streams to capture changes and replicate them separately.
Global tables automatically replicate using the same technology; adding custom replication is unnecessary and does not explain the behavior.
Distractor review
The developer must enable strong consistency reads on the replica table.
Strong consistency reads are not available for global table replicas; they are only supported for the table in the region where the read is performed and only for that table's own data.
Distractor review
The global table must be configured with write forwarding.
Write forwarding ensures writes are applied to the primary region but does not affect read consistency across regions.
Common exam trap
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.
Technical deep dive
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.
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
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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?
Static NAT maps one inside address to one outside address.
What is the correct answer to this question?
The correct answer is: Global tables use asynchronous replication, introducing unavoidable replication lag. — DynamoDB global tables use asynchronous, eventually consistent replication across regions. There is a natural replication lag between regions; therefore, a read in another region may not immediately reflect writes performed in the primary region. Strong consistency reads are only supported for local tables, not across regions. DynamoDB Streams can be used for custom replication, but global tables already handle replication. Write forwarding is a feature that redirects writes to the primary region but does not affect read consistency.
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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