Amazon Web Services Updated SOA-C02 Exam Questions and Answers by asa

Content-MD5 Header:

The Content-MD5 header provides an MD5 checksum of the object being uploaded. Amazon S3 uses this checksum to verify the integrity of the object.

Steps:

When uploading an object to S3, calculate the MD5 checksum of the object.

Include the Content-MD5 header with the base64-encoded MD5 checksum value in the upload request.

This ensures that S3 can detect if the object is corrupted during the upload process.

PUT Object - Amazon Simple Storage Service

This is a classic decoupling scenario — SQS is used to buffer requests between frontend (producer) and backend (consumer) to handle sudden traffic spikes.

From SQS documentation:

SQS is a fully managed message queuing service that enables you to decouple and scale microservices, distributed systems, and serverless applications.

This approach ensures messages are not lost and the backend can process at its own pace.

For improving upload performance globally for an Amazon S3 bucket, enabling S3 Transfer Acceleration is the best solution. This service optimizes file transfers to S3 using Amazon CloudFront's globally distributed edge locations. After enabling this feature, uploads to the S3 bucket are first routed to an AWS edge location and then transferred to S3 over an optimized network path. Option C is correct, and the developers should use the provided accelerate endpoint in their API calls. For more details, consult the AWS documentation on S3 Transfer Acceleration Amazon S3 Transfer Acceleration.

Step-by-Step Explanation:

Understand the Problem:

The EC2 instance processes large data files and uses a 1 TB General Purpose SSD (gp2) EBS volume.

CloudWatch metrics show consistent high VolumeReadOps.

The requirement is to improve I/O performance while ensuring data integrity.

Analyze the Requirements:

Improve I/O performance.

Maintain data integrity.

Evaluate the Options:

Option A: Change the instance type to a large, burstable, general-purpose instance.

Burstable instances provide a baseline level of CPU performance with the ability to burst to a higher level when needed. However, this does not address the I/O performance directly.

Option B: Change the instance type to an extra-large general-purpose instance.

A larger instance type might improve performance, but it does not directly address the I/O performance of the EBS volume.

Option C: Increase the EBS volume to a 2 TB General Purpose SSD (gp2) volume.

Increasing the size of a General Purpose SSD (gp2) volume can increase its IOPS. The larger the volume, the higher the baseline performance in terms of IOPS.

Option D: Move the data that resides on the EBS volume to the instance store.

Instance store volumes provide high I/O performance but are ephemeral, meaning data will be lost if the instance is stopped or terminated. This does not ensure data integrity.

Select the Best Solution:

Option C: Increasing the EBS volume size to 2 TB will provide higher IOPS, improving I/O performance while maintaining data integrity.

Amazon EBS Volume Types

General Purpose SSD (gp2) Volumes

Increasing the size of the General Purpose SSD (gp2) volume is an effective way to improve I/O performance while ensuring data integrity remains intact.