AWS Certified Solutions Architect – Professional — Question 458

An International company has deployed a multi-tier web application that relies on DynamoDB in a single region. For regulatory reasons they need disaster recovery capability in a separate region with a Recovery Time Objective of 2 hours and a Recovery Point Objective of 24 hours. They should synchronize their data on a regular basis and be able to provision me web application rapidly using CloudFormation.
The objective is to minimize changes to the existing web application, control the throughput of DynamoDB used for the synchronization of data and synchronize only the modified elements.
Which design would you choose to meet these requirements?

Answer options

• A. Use AWS data Pipeline to schedule a DynamoDB cross region copy once a day, create a ג€Lastupdatedג€ attribute in your DynamoDB table that would represent the timestamp of the last update and use it as a filter.
• B. Use EMR and write a custom script to retrieve data from DynamoDB in the current region using a SCAN operation and push it to DynamoDB in the second region.
• C. Use AWS data Pipeline to schedule an export of the DynamoDB table to S3 in the current region once a day then schedule another task immediately after it that will import data from S3 to DynamoDB in the other region.
• D. Send also each Ante into an SQS queue in me second region; use an auto-scaling group behind the SQS queue to replay the write in the second region.

Correct answer: A

Explanation

Option A is the most efficient solution because using AWS Data Pipeline to schedule a daily copy with a 'LastUpdated' attribute filter allows the system to synchronize only modified elements, thereby minimizing throughput consumption on DynamoDB. Option B is inefficient and costly as a SCAN operation reads the entire table instead of targeting only modified elements. Option C is incorrect because exporting and importing the entire table via S3 does not filter for only modified items, violating the requirement to minimize throughput and only sync changes.