Lab 03 - EC2 Elastic IP
Difficulty: Beginner Service: Amazon EC2
Cost: This lab uses a t2.micro instance (Free Tier eligible) and allocates one Elastic IP. An unassociated Elastic IP costs ~$0.005/hour (~$0.12/day) and is not covered by the Free Tier. This charge applies from the moment the stack is deployed until the EIP is associated or the stack is deleted. Complete the lab and delete the stack promptly.
If left running outside the Free Tier, the total cost is approximately $0.42/day (instance $0.28 + EBS $0.02 + unassociated EIP $0.12). Once you associate the EIP as part of the fix, the EIP charge stops and the cost drops to approximately $0.30/day.
Scenario
Your team deployed a web server on EC2. The stack completed successfully, the instance is
running, and the security group allows traffic on ports 80 and 22. The route table points to
the internet gateway. Everything looks configured correctly — but the WebPageURL in the
stack Outputs doesn’t load.
What Was Deployed
| Resource | Purpose |
|---|---|
AWS::EC2::VPC |
Dedicated VPC for the lab |
AWS::EC2::Subnet |
Subnet — note that auto-assign public IP is disabled |
AWS::EC2::InternetGateway |
Internet gateway attached to the VPC |
AWS::EC2::RouteTable |
Route table with a default route to the internet |
AWS::EC2::SecurityGroup |
Allows inbound traffic on ports 80 and 22 |
AWS::EC2::EIP |
An Elastic IP address |
AWS::EC2::Instance |
t2.micro running Amazon Linux 2023 with a web server |
The stack deployed without errors. Apache is running on the instance.
Deploy the Lab
- Open the AWS CloudFormation console
- Click Create stack > With new resources (standard)
- Select Upload a template file and upload lab-03-ec2-elastic-ip.yaml
- Enter a stack name (e.g.,
brokenlabs-ec2-lab-03) and click Next > Next > Submit - Wait for the stack status to reach CREATE_COMPLETE (takes 2–3 minutes)
- Open the stack Outputs tab — you will see
InstanceId,ElasticIPAddress, andWebPageURL
The Problem
Open the WebPageURL from the stack Outputs in your browser.
Expected: the AWS Broken Labs welcome page loads. Actual: the browser displays:
This site can't be reached
ERR_CONNECTION_TIMED_OUT
The security group, routing, and Apache are all correct. Something else is preventing the instance from being reachable from the internet.
Fix the Lab
Investigate the instance’s network configuration. Check whether the instance has a public
IP address. Look at the ElasticIPAddress Output — what is it associated with?
Need help? Open hints.md for progressive hints.
Cleanup
Important: If you associated the Elastic IP as part of the fix, you must disassociate it before deleting the stack. CloudFormation cannot delete an EIP that has been manually associated outside the stack.
To disassociate: EC2 → Elastic IPs → select the EIP → Actions → Disassociate Elastic IP address → Disassociate. Then delete the stack.
If you did not associate the EIP, delete the stack directly.
- Open CloudFormation, select your stack, and click Delete
- Wait for the stack to reach DELETE_COMPLETE (or disappear from the list)
- Verify in the EC2 console that the instance no longer appears (or shows Terminated)
- Verify under Elastic IPs that no address from this lab remains