Question 73 of 247
How to Create a CloudWatch Alarm for EC2 CPU Utilization
A SysOps administrator needs to monitor the CPU utilization of an Amazon EC2 instance and receive an email notification when the metric exceeds 90% for 5 consecutive minutes. The solution should use the least operational overhead. Which combination of AWS services should be used?
Quick Answer
The correct combination is a CloudWatch alarm on the CPUUtilization metric paired with an Amazon SNS topic for email notifications. This works because the alarm directly evaluates the metric over a specified number of consecutive periods—here, five 1-minute periods—triggering when the average CPU utilization exceeds 90%, and then publishes the state change to the SNS topic, which handles the email delivery without any additional servers or code. On the AWS Certified SysOps Administrator Associate SOA-C02 exam, this scenario tests your understanding of native monitoring integrations and the principle of minimizing operational overhead; a common trap is overcomplicating the solution by adding Lambda or EC2 instances for notification logic. Remember the key: CloudWatch alarms are the simplest way to react to metric thresholds, and SNS is the default notification channel. A useful memory tip is “Alarm + SNS = No extra mess,” reinforcing that direct metric-to-notification linkage avoids unnecessary infrastructure.
⚠ Common exam trap
The trap here is that candidates may overcomplicate the solution by introducing Lambda or log-based filters, when the simplest and most direct path—a CloudWatch alarm on the existing CPUUtilization metric with an SNS action—is the correct answer for minimal operational overhead.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Create a CloudWatch alarm on the CPUUtilization metric and configure the alarm to send a notification to an Amazon SNS topic with email subscriptions.
A CloudWatch alarm directly monitors the CPUUtilization metric for an EC2 instance and can be configured to evaluate whether the metric exceeds 90% for 5 consecutive minutes (e.g., 5 evaluation periods of 1 minute each). The alarm then publishes to an Amazon SNS topic, which sends email notifications to subscribed endpoints, requiring no additional infrastructure or code, thus minimizing operational overhead.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Create a CloudWatch alarm on the CPUUtilization metric and configure the alarm to send a notification to an Amazon SNS topic with email subscriptions.
Why this is correct
This is the simplest approach. CloudWatch natively monitors EC2 metrics and can trigger SNS notifications without any custom code.
- ✗
Create an Amazon EventBridge rule that triggers an AWS Lambda function to check the CPUUtilization metric and send an email via Amazon SES.
Why it's wrong here
This adds unnecessary complexity. CloudWatch alarms already provide the needed evaluation and SNS integration.
- ✗
Configure the EC2 instance to publish CPU logs to Amazon CloudWatch Logs, then create a metric filter to detect high CPU and trigger an SNS notification.
Why it's wrong here
CPU utilization is already available as a CloudWatch metric, not a log. This approach is inefficient and requires custom log publishing.
- ✗
Use AWS CloudTrail to monitor EC2 CPU metrics and send notifications to an Amazon SQS queue.
Why it's wrong here
CloudTrail records API calls, not performance metrics. It cannot monitor CPU utilization.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Same concept, more angles
2 more ways this is tested on SOA-C02
These questions test the same concept from different angles. Work through them to make sure you can recognise it however the exam phrases it.
Variation 1. A SysOps administrator needs to monitor the CPU utilization of an Amazon EC2 instance and receive an alert if it exceeds 80% for 10 consecutive minutes. The instance is in a VPC with no Internet access. What is the MOST efficient way to meet these requirements?
easy- A.Use AWS Systems Manager to run a script on the instance that checks CPU and sends an SNS notification.
- ✓ B.Create a CloudWatch alarm on the CPUUtilization metric with a period of 5 minutes and an evaluation period of 2.
- C.Enable detailed monitoring on the EC2 instance and create a CloudWatch alarm on the CPUUtilization metric.
- D.Install the CloudWatch agent on the EC2 instance to collect CPU metrics and create a CloudWatch alarm.
Why B: A CloudWatch alarm with a period of 5 minutes and an evaluation period of 2 means the alarm evaluates two consecutive 5-minute data points, totaling 10 minutes. Since the EC2 instance is in a VPC with no Internet access, CloudWatch metrics are still reported via the CloudWatch service endpoint within the VPC (or via VPC endpoints), so no additional agent or script is needed. This is the most efficient approach as it uses native CloudWatch functionality without requiring any custom scripts or additional software.
Variation 2. A SysOps administrator needs to monitor the CPU utilization of an Amazon EC2 instance and send an alert when it exceeds 90% for 5 consecutive minutes. Which combination of AWS services should the administrator use to meet this requirement?
easy- ✓ A.Amazon CloudWatch metric (CPUUtilization), a CloudWatch alarm, and an Amazon SNS topic.
- B.Amazon CloudWatch Logs, a metric filter to extract CPU utilization from logs, and an alarm on that metric.
- C.A CloudWatch dashboard and an AWS Lambda function that checks the dashboard periodically.
- D.Amazon EventBridge (CloudWatch Events) and a Lambda function that calls the EC2 DescribeInstances API.
Why A: The correct approach is to use a CloudWatch metric for CPUUtilization, which is automatically published by EC2 instances. A CloudWatch alarm can be configured to evaluate this metric over a period of 5 consecutive minutes with a threshold of 90%, and when the alarm state is triggered, it publishes to an SNS topic to send notifications. This is the native, efficient, and recommended method for monitoring and alerting on EC2 CPU utilization.
Last reviewed: Jun 11, 2026
This SOA-C02 practice question is part of Courseiva's free Amazon Web Services certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the SOA-C02 exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.