AWS Certified Associate SOA-C02 Reddit Questions

Objective:

Receive a notification when both disk space usage and DiskReadOps exceed threshold values.

Composite Alarms:

Composite alarms allow combining multiple metric alarms into a single alarm. Notifications are triggered only when all conditions are met.

Steps to Implement:

Step 1: Install the CloudWatch agent on the EC2 instances and configure it to monitor disk space.

Step 2: Create individual metric alarms:

One for disk space usage.

One for the DiskReadOps metric.

Step 3: Create a composite alarm:

Include both metric alarms.

Configure the composite alarm to send notifications to the SNS topic when both conditions are met.

AWS References:

Composite Alarms in CloudWatch:Creating Composite Alarms

CloudWatch Agent Installation:Install CloudWatch Agent

Why Other Options Are Incorrect:

Option B: This would trigger notifications for either condition, not both simultaneously.

Option C: EBSByteBalance% is unrelated to free disk space.

Option D: Detailed monitoring is not required for composite alarms.

Step-by-Step Explanation:

AWS Budgets Overview:

AWS Budgets enables you to set custom cost and usage budgets, and it provides alerts when you exceed those thresholds. It is designed for cost management with minimal operational overhead.

Recurring Cost Budget Creation:

Go to the AWS Budgets Console.

Select Create a budget.

Choose the Cost budget option.

Define whether this budget tracks actual costs or forecasted costs (you will create two budgets, one for each).

Configure the Budget Thresholds:

Set your budget thresholds for both actual costs and forecasted costs.

For example:

Actual Costs Alert: Budget = $1000, Alert at 80% usage ($800).

Forecasted Costs Alert: Budget = $1000, Alert at forecasted usage exceeding 80% ($800).

Alert Configuration:

In the budget creation process, enable Notifications and Actions.

Specify the email addresses or an Amazon SNS Topic to receive alerts.

Set up alerts for both:

Actual Cost Exceeding Budget.

Forecasted Cost Exceeding Budget.

Amazon SNS Setup:

If using an SNS topic, ensure an Amazon SNS topic is created.

Grant appropriate permissions for the Budget service to publish to the SNS topic.

Add subscribers (e.g., email addresses or endpoints) to the SNS topic.

Automation and Monitoring:

Once set up, AWS Budgets continuously monitors actual and forecasted costs.

Alerts are sent automatically when thresholds are breached, reducing manual overhead and reliance on periodic monitoring.

Why This is the Best Option (Least Operational Overhead):

AWS Budgets directly integrates with SNS, allowing real-time alerts without building custom workflows or parsing reports.

It is a native AWS service specifically designed for cost tracking, minimizing complexity and setup time.

No custom code or additional services like Lambda or Step Functions are required, reducing operational maintenance.

In this scenario, the issue is that the EC2 instances are marked healthy by status checks, but the website is still intermittently failing, returning HTTP 500 errors.

This indicates that the OS-level checks are passing, but the application is not behaving properly. To resolve this, the Auto Scaling group must use ALB (ELB) health checks which verify application-level health, not just EC2 status.

From the Auto Scaling User Guide:

By default, an Auto Scaling group uses EC2 instance status checks to determine the health state of an instance. You can optionally configure the Auto Scaling group to use Elastic Load Balancing health checks in combination with EC2 status checks.

These health checks allow Auto Scaling to detect application failures and replace unhealthy instances automatically.

❌ Why the other options are incorrect:

A. Network Load Balancer is for TCP-level traffic and does not solve HTTP 500 errors.

C. Sticky sessions are used for session persistence and don’t solve server errors.

D. Installing CloudWatch agents and rebooting is reactive and not an automated health check replacement system.

Amazon EFS supports two forms of encryption for file systems, encryption of data in transit and encryption at rest. You can enable encryption of data at rest when creating an Amazon EFS file system. You can enable encryption of data in transit when you mount the file system.