🚀 Deploying a URL Shortener App on AWS EC2 with Auto Scaling and Load Balancer

#webdev #devops #cloud #aws

In this blog post, I’ll walk you through how I successfully deployed my URL Shortener app using AWS EC2, and how I laid the foundation for high availability by preparing for Auto Scaling Groups (ASG) and Load Balancers.

Step 1: Prepare Your Application

My project is a URL Shortener App. Before deploying, I did the following:

Created a GitHub repository for the project.
Ensured the app runs locally using Flask (or your framework of choice).
Prepared requirements.txt for Python dependencies.
Check my Repo if Needed.

Step 2: Launch an EC2 Instance

Go to the AWS EC2 Dashboard.
Click on "Launch Instance".
Choose:
Amazon Linux 2 or Ubuntu
Instance type: t2.micro (free tier eligible)
Under Key pair, create a new key pair or select an existing one and download the .pem file.
Create a Security Group:
Port 22 (SSH) → 0.0.0.0/0
Port 80 (HTTP/frontend) → 0.0.0.0/0
Port 5000 (Flask backend) → 0.0.0.0/0
Launch the instance!

Step 3: Connect to Your EC2 via SSH

Using Git Bash or terminal:

ssh -i your-key.pem ec2-user@<your-ec2-public-ip>

Replace <your-key.pem> with your downloaded key and with your instance’s IP.

Step 4: Set Up and Run Your App on EC2

inside your EC2 terminal:

# Update and install Git + Python
sudo yum update -y
sudo yum install git python3 -y

# Clone your GitHub repo
git clone https://github.com/yourusername/your-repo.git
cd your-repo

# Install dependencies
pip3 install -r requirements.txt

# Run the app
python3 app.py

If your Flask app runs on port 5000, you should now be able to access it at:

http://<your-ec2-public-ip>:5000

Step 5: Create an AMI (Amazon Machine Image)

To use the current EC2 setup for Auto Scaling:

Go to EC2 > Instances.
Select your running instance.
Click Actions > Image > Create Image.
Name it url-shortener-ami and save.

Step 6: Create a Launch Template

Go to EC2 > Launch Templates.
Click Create Launch Template.
Fill in:
Name: url-shortener-template
Choose the AMI you just created
Select instance type (e.g., t2.micro)
Create the template.

Step 7: Create an Auto Scaling Group (ASG)

Go to EC2 > Auto Scaling > Auto Scaling Groups.
Click Create Auto Scaling Group.
Choose your Launch Template.
Set:
Group size: e.g., min: 1, max: 3
VPC + subnets

Step 8:Attach a Load Balancer

Create a Target Group first (protocol: HTTP, port: 80)
Register instances with the target group
Use Application Load Balancer (ALB)
Configure health checks and scaling policies.
Review and create the ASG.

Step 9:Test Everything:

Check the EC2 Instance with it's Public IP weather our app can accessible.

Check the ALB using Its DNS Name weather it balancing the load.
Check the Health of ASG and also it shows(in - service)

Step 10:

For saving cost and doing all these within Free tier:

Stop the EC2 Instances After the work has been Completed.
Delete the ASG and Load Balancer to avoid Charges.
Un register the AMI and Snapshot and Launch Templates to avoid additional Payments.