Q56 — AWS SAA-C03 Ch.10

Question 56 of 100 | ← Chapter 10

Q656. A solutions architect is designing a shared storage solution for a web application that is deployed across multiple Availability Zones. The web application runs on Amazon EC2 instances that are in an Auto Scaling group. The company plans to make frequent changes to the content. The solution must have strong consistency in returning the new content as soon as the changes occur.Which solutions meet these requirements? (Select TWO.)

Correct Answer: B. Create an Amazon Elastic File System (Amazon EFS) file system. Mount the EFS file system on the individual EC2 instances., E. Create an Amazon S3 bucket to store the web content. Set the metadata for the Cache-Control header to no-cache. Use Amazon CloudFront to deliver the content.

Explanation

To design a shared storage solution for a web application deployed across multiple Availability Zones, with strong consistency in returning new content as soon as changes occur, the following solutions would meet these requirements:B. Create an Amazon Elastic File System (Amazon EFS) file system. Mount the EFS file system on the individual EC2 instances.E. Create an Amazon S3 bucket to store the web content. Set the metadata for the Cache-Control header to no-cache. Use Amazon CloudFront to deliver the content.Here's the rationale behind these solutions:Option B: Create an Amazon Elastic File System (Amazon EFS) file system. Mount the EFS file system on the individual EC2 instances.Amazon EFS provides a scalable and managed file storage service that can be shared across multiple EC2 instances. By creating an EFS file system and mounting it on the individual EC2 instances, the web application can access a shared storage solution with strong consistency. Any changes made to the content will be immediately visible to all instances accessing the EFS file system.Option E: Create an Amazon S3 bucket to store the web content. Set the metadata for the Cache-Control header to no-cache. Use Amazon CloudFront to deliver the content. By storing the web content in an Amazon S3 bucket and setting the metadata for the Cache-Control header to no-cache, you ensure that CloudFront, the content delivery network (CDN) service, retrieves the latest content from the S3 bucket for each user request. CloudFront will serve the new content as soon as changes occur, providing strong consistency. CloudFront also helps improve the performance of content delivery by caching the content at edge locations closer to the end-users.Option A: Use AWS Storage Gateway Volume Gateway Internet Small Computer Systems Interface (iSCSI) block storage that is mounted to the individual EC2 instances. AWS Storage Gateway Volume Gateway provides block storage that can be mounted to EC2 instances using iSCSI. While this solution provides shared storage, it may not offer strong consistency for returning new content as soon as changes occur, as it depends on the configuration and synchronization mechanisms in place.Option C: Create a shared Amazon Elastic Block Store (Amazon EBS) volume. Mount the EBS volume on the individual EC2 instances.Amazon EBS provides block storage volumes that can be attached to EC2 instances. While it is possible to create a shared EBS volume, it does not inherently offer strong consistency for returning new content as soon as changes occur. It would require additional mechanisms like distributed file systems or synchronization processes to achieve that level of consistency.Option D: Use AWS DataSync to perform continuous synchronization of data between EC2 hosts in the Auto Scaling group.AWS DataSync is a data transfer service that can be used to perform continuous synchronization of data between different locations. While it can be used for data synchronization, it may not provide the exact level of strong consistency required for returning new content as soon as changes occur.Therefore, the most suitable solutions that meet the requirements of a shared storage solution with strong consistency for returning new content as soon as changes occur are to create an Amazon Elastic File System (Amazon EFS) file system (Option B) and use an Amazon S3 bucket with CloudFront (Option E). Both options provide shared storage and ensure the latest content is accessible to the web application.