Exam AWS Certified Solutions Architect - Professional SAP-C02 topic 1 question 507 discussion

Mountpoint for Amazon S3: This solution allows the EC2 instances to directly access the S3 bucket as if it were a local file system. This ensures that the instances always access the latest version of the pricing file without having to download it each time. Cost-Effective: This approach avoids the need to constantly download and store the file on each instance, which can save on both S3 GET requests and local storage costs. Simplicity: By mounting the S3 bucket, you ensure that all instances are using the most current file without additional logic or processes to manage file updates.

DynamoDB in this scenario looks cheaper than EFS. Answer A

Option C (Mountpoint for S3) (best solution): Mountpoint for Amazon S3 allows the EC2 instances to directly access the latest version of the pricing file stored in S3 without repeatedly downloading it. Each EC2 instance will always read the most up-to-date file directly from S3, eliminating the risk of outdated information. This solution is cost-effective as it involves minimal overhead, does not incur unnecessary data transfer or operational complexity, and requires minimal application modification.

"Mountpoint for Amazon S3 is available only for Linux operating systems. You can use Mountpoint to access S3 objects in all storage classes except S3 Glacier Flexible Retrieval, S3 Glacier Deep Archive, S3 Intelligent-Tiering Archive Access Tier, and S3 Intelligent-Tiering Deep Archive Access Tier." https://docs.aws.amazon.com/AmazonS3/latest/userguide/mountpoint.html

By leveraging the strong consistency guarantees, cost-effectiveness, and simplicity of Mountpoint for Amazon S3, Option C provides the most appropriate and cost-effective solution for ensuring the EC2 instances in the Auto Scaling group always have access to the latest pricing information, resolving the outdated pricing data problem. The other options have drawbacks or are less cost-effective: Option A: Using DynamoDB may not be cost-effective for storing and accessing a large, frequently updated pricing file with several thousand line items. Option B: While Amazon EFS is viable, it introduces additional infrastructure and potential costs compared to directly accessing the pricing file from the S3 bucket using Mountpoint for Amazon S3. Option D: Using an Amazon EBS volume with Multi-Attach would require updating the pricing file on the volume whenever a new instance launches, which is less efficient and more prone to errors than directly accessing the file from the S3 bucket.

Option C is most cost effective, but the question has ambiguity where it tells customer could be wrongly charged, more details should be provided on the same to understand if wrong charging is critical or not. If wrong charging is critical and needs low latency and more reliability on the queried data then its option A

most cost effective

none of them makes sense... if an S3 object is uploaded it is strongly consist since end 2020, eventual consistency is a matter of the past. So it doesn't matter if the lambda function get the trigger after upload and transfer the information to dynamodb (A) or EFS(b), or the ec2 instance get the object via blocklevel file access (C) or EBS (D). The consistency is being provided by the source system which is S3, so nothing helps here. From the cost perspective is C the cheapest

Mountpoint for Amazon S3 allows EC2 instances to treat an S3 bucket like a file system. This solution ensures that the EC2 instances always have access to the latest version of the pricing file, as the file is directly accessed from S3. You avoid downloading the file every time and reduce the risk of using outdated pricing data. S3 Consistency: Amazon S3 provides strong read-after-write consistency, so any update to the pricing file in S3 will be immediately visible to all EC2 instances accessing the file via the mount point. Cost Efficiency: By using Mountpoint for Amazon S3, you leverage S3's cost-effective storage and avoid additional infrastructure like DynamoDB or Elastic File System (EFS). This solution does not require copying data to another storage system, minimizing overhead.

the question is asking about cost effectiveness so why choose A to add additional service like Dynamodb . I will go for option C

A. DynamoDB provides fast data access and query capabilities, suitable for frequently read but infrequently updated data. B. EFS may not be suitable for frequent small file updates, and its cost may be higher than using DynamoDB. C. This solution can directly read pricing files from S3, but it does not solve the problem of outdated pricing data being used by old instances even after the pricing files are updated. D. EBS is not good at Multi Attach to multiple EC2 instances, and it can increase complexity and cost.

Option A is the correct answer.

There is no need to move away from S3