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

By exporting AWS Cost and Usage Reports (CUR) to Amazon S3 and analyzing them with Amazon QuickSight, companies can generate interactive visual dashboards. This solution is fully AWS-managed, requires no third-party tools, and integrates deeply with AWS cost data.

This solution directly addresses the scalability and high availability requirements with minimal downtime.

Additional Reader Instances: Adding more reader instances to the Aurora cluster will distribute the read load, improving the performance of the application under heavy read traffic. Aurora reader instances automatically replicate the data from the writer instance, enabling you to scale out read operations.

Amazon RDS Proxy: RDS Proxy improves database availability by managing database connections more efficiently and providing a connection pool. This reduces the overhead on the Aurora cluster during peak loads, further enhancing performance and availability without requiring changes to the application code.

Why Not Other Options?:

Option A (EventBridge and Lambda): This doesn’t directly address the performance and availability issues. Logging state changes and adding reader nodes on failure events doesn’t provide proactive scalability.

Option B (Zero-Downtime Restart and Activity Streams): Zero-Downtime Restart (ZDR) is useful for minimizing downtime during maintenance but doesn’t directly improve scalability. Database Activity Streams are more for security monitoring than for performance enhancement.

Option D (ElastiCache for Redis): While adding a caching layer can help with read performance, it introduces complexity and may not be necessary if additional reader instances can handle the load.

AWS References:

Amazon Aurora Scaling- Information on scaling Aurora clusters with reader instances.

Amazon RDS Proxy- Details on how RDS Proxy can improve database performance and availability.

Comprehensive and Detailed Explanation:

To prevent loss of access to the AWS root user account due to a lost MFA device, AWS recommends enabling multiple MFA devices for the root user.

Multiple MFA Devices: AWS allows up to eight MFA devices (virtual, hardware, or security keys) to be associated with a single root user account. This redundancy ensures that if one device is lost, others can be used to authenticate and access the account.

Security Best Practices: Implementing multiple MFA devices enhances account security and provides resilience against potential access issues.

By proactively setting up multiple MFA devices, the company can maintain uninterrupted access to its critical AWS resources, even in the event of a lost or malfunctioning MFA device.

The IAM policy includes two statements:

1️⃣ Allow ec2:TerminateInstances on all resources

2️⃣ Deny ec2:TerminateInstances if the request does NOT come from:

192.0.2.0/24

203.0.113.0/24

AWS IAM policy evaluation rules state:

Explicit Deny always overrides Allow.

A request must meet all applicable conditions in the policy to be granted.

aws:SourceIp condition applies when IAM actions are invoked via the public AWS APIs.

In this scenario, the administrator is not originating the request from one of the allowed CIDR blocks, so the Deny condition is triggered, overriding the Allow statement.

Therefore, the operation is blocked with:

403 AccessDenied: explicit deny

This matches the behavior described in the AWS IAM Policy Evaluation Logic used in the Security Pillar of the Well-Architected Framework:

Explicit Deny > Allow > Default Deny

IP-based Conditions restrict API calls originating outside approved network ranges

Options A/B/C do not accurately reflect this explicit Deny condition behavior.