Day 25.Setting Up an EC2 Instance and CloudWatch Alarm

Source: Dev.to

Lab Information

The Nautilus DevOps team needs to set up an EC2 instance for their application and create a CloudWatch alarm to monitor CPU utilization. The alarm must trigger if CPU utilization exceeds 90 % for one consecutive 5‑minute period. Notifications should be sent to the existing SNS topic datacenter-sns-topic.

Step 1: Launch the EC2 Instance

1. AWS Console → EC2 → Launch instance
2. Configure instance
   • Name: datacenter-ec2
   • AMI: Ubuntu Server (20.04 LTS or 22.04 LTS)
   • Instance type: t2.micro (or any allowed type)
   • Key pair: Select or create one (lab choice)
   • Network: Default VPC, default subnet
   • Security group: Allow SSH (port 22)
3. Launch
   • Click Launch instance
   • Wait until the instance state is Running and status checks are 2/2 passed

Step 2: Create the CloudWatch Alarm

1. AWS Console → CloudWatch → Alarms → Create alarm
2. Select the Metric
   • Click Select metric → EC2 → Per-Instance Metrics → CPUUtilization
   • Choose the metric for datacenter-ec2 and click Select metric
3. Configure Alarm Conditions
   • Alarm state trigger: In alarm
   • Threshold type: Static
   • Whenever CPUUtilization is ≥ 90 % for 5 minutes (period)
   • Send notification to: Select existing SNS topic → datacenter-sns-topic
4. Name the Alarm
   • Alarm name: datacenter-alarm
   • Description (optional): Alarm when CPU exceeds 90 % for 5 minutes
   • Click Create alarm

Step 3: Verify Configuration

• Initial state: OK (normal)
• Metric: CPUUtilization
• Threshold: ≥ 90 %
• Period: 5 minutes
• SNS Action: Alarm action shows datacenter-sns-topic