SOA-C02 Monitoring, Logging, and Remediation Practice Question

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

• ✗

  Use AWS Systems Manager to run a script on the instance that checks CPU and sends an SNS notification.

  Why it's wrong here

  Using Systems Manager to run a script requires the instance to have outbound internet access or a VPC endpoint for Systems Manager, which is absent in this isolated VPC, so the script cannot call the SNS API. This approach is tempting because Systems Manager is commonly used for automated remediation and script execution on EC2 instances, and would be correct if the VPC had a Systems Manager VPC endpoint configured.

• ✓

  Create a CloudWatch alarm on the CPUUtilization metric with a period of 5 minutes and an evaluation period of 2.

  Why this is correct

  This is the correct approach because EC2 instances automatically emit CPUUtilization metrics every 5 minutes under basic monitoring, so a CloudWatch alarm with a period of 5 minutes will have the data it needs without any extra configuration. An evaluation period of 2 means the alarm only enters ALARM state after two consecutive data points breach the threshold, which reduces false positives from transient spikes. This is the simplest, most cost-effective way to monitor CPU utilization on an EC2 instance.

• ✗

  Enable detailed monitoring on the EC2 instance and create a CloudWatch alarm on the CPUUtilization metric.

  Why it's wrong here

  Enabling detailed monitoring is unnecessary here because it pushes metrics at 1-minute intervals, but the alarm in question uses a 5-minute period, which aligns perfectly with basic monitoring's default 5-minute data points. While detailed monitoring would still work, it incurs additional charges and provides no benefit for a 5-minute evaluation window. Therefore, this option is technically functional but wasteful, making it incorrect when a basic-monitoring alarm fully satisfies the requirement at lower cost.

• ✗

  Install the CloudWatch agent on the EC2 instance to collect CPU metrics and create a CloudWatch alarm.

  Why it's wrong here

  The CloudWatch agent collects OS-level metrics such as memory usage, disk space, and custom application metrics; it is not required for CPU utilization, which is already reported by the EC2 hypervisor to CloudWatch automatically as the CPUUtilization metric. Installing the agent adds operational overhead—installing, configuring, and managing a new component—and is unnecessary for this basic monitoring task. This option is wrong because it misconceives the need for an agent when the native metric is already available.

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