Amazon Web Services Updated SAA-C03 Exam Questions and Answers by lia

AWS DataSync provides a fully managed, secure, and high-performance service for transferring large amounts of data between on-premises storage and Amazon S3. It uses TLS encryption in transit and automates data validation, scheduling, and monitoring.

From AWS Documentation:

“AWS DataSync securely and efficiently transfers large amounts of data online between on-premises storage and AWS services. All data is encrypted in transit using TLS.”

(Source: AWS DataSync User Guide – How DataSync Works)

Why B is correct:

Encrypts all data in transit automatically.

Optimized for high-throughput WAN environments (100 Mbps to multi-Gbps).

Fully managed, with no need to provision additional infrastructure.

Integrates natively with S3 and supports incremental syncs.

Why others are incorrect:

A: DMS is designed for database migration, not unstructured data.

C: Snowball is for offline migrations, not needed given available connectivity.

D: Direct Connect is costly for temporary data transfers and unnecessary here.

Amazon EFS requires a mount target in each Availability Zone where EC2 instances access the file system. This is because each mount target provides an elastic network interface in the subnet and AZ, reducing network latency by allowing EC2 instances to communicate locally with the EFS mount target. Creating a mount target in each AZ optimizes file system access performance and availability. Instances mount the EFS file system via the mount target in their respective AZ, which provides the lowest possible latency and avoids cross-AZ traffic.

Option A, with only a single mount target in the VPC, will cause cross-AZ traffic for instances in other AZs, increasing latency and potentially incurring data transfer costs. Option B is incomplete and introduces complexity with sharing directories across instances. Option C is invalid because mount targets are per AZ and per subnet, not per instance.

The best practice for granting AWS resource access to EC2 instances is to use IAM roles, not users or long-lived access keys. You create an IAM role with a policy that grants the minimum permissions required, then attach that role to an instance profile associated with the EC2 instance. The instance then automatically receives temporary credentials for AWS service access.

AWS Documentation Extract:

" Attach an IAM role to your EC2 instances to securely grant permissions to AWS services according to the principle of least privilege. Never embed access keys in EC2 instances. "

(Source: AWS EC2 documentation, IAM Roles for EC2)

A, B: Using IAM users and embedding keys violates security best practices.

C: IAM role credentials are automatically managed and never need to be manually attached as keys.

Workload Discovery on AWS is a tool that automatically discovers AWS resources across multiple accounts and Regions and builds visual architecture diagrams that show resource relationships. It is specifically designed to help teams understand and document existing workloads with minimal manual effort.

This service provides multi-account visibility, relationship mapping, and exportable diagrams, which directly satisfies the need to “build and map the relationship details of the various workloads” with the least operational overhead.

Systems Manager Inventory (Option A) focuses on collecting configuration and inventory data (primarily for instances and some resources) and does not generate architecture diagrams or full relationship views.

Step Functions (Option B) and X-Ray (Option D) would require custom collection and manual diagramming and are not purpose-built for environment discovery and mapping.