Amazon Web Services SAA-C03 - AWS Certified Solutions Architect - Associate (SAA-C03)

AWS recommends using cost allocation tags to associate costs with owners (e.g., department, project) and AWS Budgets to create cost or usage budgets with alerts at defined thresholds (e.g., 60%). Budgets can send notifications via email or Amazon SNS when “Actual or forecasted” spend exceeds the threshold. Cost Explorer forecasts help visualize trends but do not provide budget alerting or ownership attribution by themselves. Trusted Advisor does not generate budget threshold alerts. Therefore, tagging resources for accountability and setting a budget with a 60% alert provides governance and proactive notifications aligned with cost control best practices for experimentation.

Amazon FSx for ONTAP supports both NFS and SMB protocols and includes automated tiering between SSD and capacity pool storage, optimizing cost and performance. It is ideal for mixed operating systems and varied access patterns with minimal administrative overhead.

Key Requirements:

Host the frontend on AWS as a static website.

Protect the application from common web vulnerabilities.

Minimal operational overhead.

Analysis of Options:

Option A:

Hosting the frontend on EC2 with an ALB introduces unnecessary complexity for serving static content.

AWS WAF rules can protect the ALB, but managing EC2 instances adds operational overhead.

Incorrect Approach:High operational complexity for a simple static website.

Option B:

Amazon CloudFront:Acts as a global CDN, reducing latency and protecting against DDoS attacks.

Multiple Origins:Allows static content to be served from S3 while routing API traffic to the on-premises backend.

AWS WAF:Integrates with CloudFront to provide web application protection.

Correct Approach:Offers low operational overhead with optimal security and performance.

Option C:

Using NLB and Network Firewall is unnecessary for a static website. This approach increases cost and complexity without addressing the frontend requirements effectively.

Incorrect Approach:Over-engineered solution.

Option D:

Hosting the frontend on S3 and using API Gateway is a viable option, but managing AWS WAF rules separately for both the S3 bucket and the REST API increases complexity.

Incorrect Approach:Less efficient than using CloudFront with multiple origins.

AWS Solution Architect References:

Amazon CloudFront Overview

AWS WAF with CloudFront

AWS Global Accelerator improves the performance and availability of applications by directing user traffic through the AWS global network of edge locations using anycast IP addresses. It reduces latency and jitter for global users accessing applications in a single Region.

Why this works:

Global Accelerator routes user requests to the nearest AWS edge location using AWS’s high-performance backbone network.

It then forwards traffic to the optimal endpoint — in this case, the public API hosted on EC2.

This is much more cost-effective and requires less operational complexity than deploying and maintaining multiple API Gateway endpoints across regions (Option B), or setting up Direct Connect links for every international location (Option A).

Option C requires no application change and is designed specifically for latency improvement and high availability.

🔗 References:

AWS Global Accelerator Documentation

Use Cases for Global Accelerator

Performance Improvements for Global Users

Security groups are stateful, but they cannot explicitly deny traffic — only allow.

Network ACLs are stateless and support explicit deny rules.To prevent Application A from sending traffic to Application B, configure a deny outbound rule in the network ACL of Application A’s subnet to block traffic to Application B’s subnet.

“Unlike security groups, network ACLs support both allow and deny rules, enabling you to explicitly block traffic.”

— Network ACLs

This is the correct method to block outbound traffic between subnets.

TheAWS WAF Bot Control managed ruleis designed to automatically detect and mitigate bot traffic. This feature is particularly useful for addressing malicious traffic and conserving compute resources by filtering unnecessary requests at the ALB level.

Option A:Blocking IP addresses manually introduces significant operational overhead and is not scalable against dynamic, worldwide malicious traffic.

Option C:AWS Shield provides DDoS protection, but the scenario does not describe a DDoS attack. WAF is better suited for managing application-layer threats like bot traffic.

Option D:The AWS WAF IP reputation rule helps block traffic from known bad IPs but may not address bot traffic effectively.

AWS Documentation References:

AWS WAF Bot Control

AWS WAF Managed Rules

Amazon S3 Intelligent-Tiering is designed for data with unknown or changing access patterns. It automatically moves data between frequent and infrequent access tiers based on usage. This tier offers immediate access to all objects, regardless of which tier they are stored in, while optimizing storage costs. S3 Intelligent-Tiering also provides the same high durability, availability, and security as other S3 storage classes and supports access from external resources using standard S3 APIs. Lifecycle policies and Glacier classes are more suitable for archival when infrequent access is predictable, but retrieval from Glacier classes is not immediate and incurs extra charges and delays.

Reference Extract from AWS Documentation / Study Guide:

"S3 Intelligent-Tiering is designed to optimize costs by automatically moving data between two access tiers when access patterns change. Data is always available and immediately accessible, making it ideal for unknown or unpredictable access patterns."

Source: AWS Certified Solutions Architect – Official Study Guide, S3 Storage Classes section.

To meet the requirements for tagging and preventing instance creation or deletion without proper tags, the company can use a combination of AWS Organizations tag policies and service control policies (SCPs).

Tag Policies: These enforce specific tag values across resources. Creating a tag policy with required values (e.g., sensitive, non-sensitive) and attaching it to the appropriate organizational unit (OU) ensures consistency in tagging.

SCPs: SCPs can be used to enforce compliance by preventing instance creation without a tag and preventing tag deletion. These policies control actions at the account level across the organization.

Key AWS features:

Tag Policieshelp standardize tags across accounts, andSCPsenforce governance by restricting actions that violate the policies.

AWS Documentation: AWS best practices recommend using tag policies and SCPs to enforce compliance across multiple accounts within AWS Organizations​.

Aurora global database is specifically designed for cross-Region disaster recovery and low-latency global reads.

It provides:

Physical storage-level replication between Regions, typically with lag of under 1 second, easily satisfying RPO 1 minute.

Fast cross-Region failover capabilities, often within minutes or less, which meets the RTO 5 minutes requirement.

You configure the primary Region as the writer cluster and additional Regions (such as us-west-1) as secondary clusters with reader endpoints. In a disaster, you promote the secondary to be the new writer.

Why others are not correct:

A: Standard cross-Region read replicas for Aurora PostgreSQL do not provide automatic multi-Region failover with the same guarantees as Aurora global database and may not meet strict RTO/RPO requirements.

C: Logical replication and custom EventBridge failover is complex, error-prone, and higher overhead compared to the managed global database feature.

D: Restoring from snapshots plus cross-Region replication is too slow to meet RTO 5 minutes and certainly cannot maintain RPO 1 minute.

AWS Compute Optimizerprovides detailed recommendations for optimizingAmazon EBS volumes, including insights into underutilized volumes, inefficient configurations, and potential cost savings. It analyzes usage patterns and provides recommendations based on historical data, making it the ideal tool for this use case.

Option A (Amazon Inspector): Amazon Inspector is for security assessments, not for cost optimization.

Option B (Systems Manager): Systems Manager does not specifically provide EBS optimization recommendations.

Option C (CloudWatch): CloudWatch metrics help monitor usage but do not offer optimization recommendations like Compute Optimizer.

AWS References:

AWS Compute Optimizer

AWS Direct Connect: Provides a dedicated network connection from your on-premises data center to AWS, ensuring low latency and consistent network performance.

Direct Connect Gateway Association:

Direct Connect Gateway: Acts as a global network transit hub to connect VPCs across different AWS regions.

Association with Transit Gateway: Enables communication between on-premises data centers and multiple VPCs connected to the transit gateway.

Transit Virtual Interface (VIF):

Create Transit VIF: To connect Direct Connect with a transit gateway.

Setup Steps:

Establish a Direct Connect connection.

Create a transit VIF to the Direct Connect gateway.

Associate the Direct Connect gateway with the transit gateway attached to the VPCs.

Cost Efficiency: This combination avoids the recurring costs and potential performance variability of VPN connections, providing a robust, low-latency hybrid network solution.

AWS Shield Advanced provides:

Advanced DDoS detection and mitigation

24/7 access to the AWS DDoS Response Team (DRT)

Real-time metrics and alerts via CloudWatch

Integrated with CloudFront, ALB, Route 53, and Global Accelerator

“Shield Advanced provides enhanced detection and mitigation for more sophisticated DDoS attacks and gives you access to the AWS DDoS Response Team (DRT).”

— AWS Shield Advanced Overview

Incorrect Options:

A (AWS WAF): For application-layer filtering only.

B (Shield Standard): Basic protection, no DRT or attack visibility.

C (Macie): Used for discovering sensitive data in S3, unrelated to DDoS.

The most efficient way for management-style reporting is AWS Cost Explorer, because it is designed for interactive cost analysis, filtering, grouping, and exporting reports without building a data pipeline. If the organization has activated cost allocation capabilities (for example, by tagging resources or using other allocation methods), Cost Explorer can present costs in a way that supports chargeback/showback and budgeting. From an operational standpoint, generating and downloading a report from Cost Explorer is quick, requires minimal setup, and is repeatable for periodic budget planning.

Option A (Athena) is powerful but typically requires setting up the Cost and Usage Report (CUR) delivery to Amazon S3, defining schemas, and writing/maintaining SQL queries. That is more operational overhead than needed when the ask is “most efficient way to obtain this report information.” Option C (billing dashboard bill download) provides invoice-style line items, but it is not optimized for slicing/grouping “by user” and may not align with departmental budgeting workflows. Option D is unrelated: AWS Budgets alerts on thresholds and forecasts; it does not generate a billed-items-by-user report.

Important nuance: “by user” reporting in AWS is usually achieved through cost allocation tags, account structure, or other allocation dimensions rather than literal per-person IAM identity billing. In practice, departments/teams/users are mapped via tagging and chargeback structures, which Cost Explorer is intended to analyze and export. As a result, Cost Explorer is the most operationally efficient tool to produce a downloadable report for budget planning.

Therefore, B best meets the requirement with the least effort and fastest path to a usable report.

Amazon Aurora Serverless v2 is ideal for applications with unpredictable or intermittent workloads. It automatically scales capacity up or down based on demand, significantly reducing costs. It supports automated backups to Amazon S3, making it suitable and cost-effective for new applications with variable traffic.