🚀 AWS Auto Scaling Group (ASG) Project

High Availability | Load Balancing | Auto Healing | Scalable Architecture

This project demonstrates a production-style AWS architecture built manually using the AWS Management Console.
It showcases real-world AWS infrastructure design, focusing on high availability, scalability, auto-healing, and load-balanced web applications.

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📌 1. Architecture Overview

This architecture deploys a highly available web application across multiple Availability Zones using:

• VPC with public subnets
• Internet Gateway + Route Tables
• Security Groups with least privilege
• EC2 instance with Apache (via user-data script)
• Custom AMI creation
• Launch Template based on AMI
• Application Load Balancer (ALB)
• Target Group (TG)
• Auto Scaling Group (ASG)

The system automatically:

• distributes traffic
• scales based on load
• replaces unhealthy EC2 instances
• maintains desired capacity

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📊 2. Architecture Diagram

Example:

AWS Architecture_ Auto Scaling Load Balancer.png

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🧩 3. Step-by-Step Implementation Flow

🔹 Step 1 — Create Networking Layer (VPC)

• Custom VPC created (CIDR example: 10.0.0.0/16)
• Two public subnets in two different AZs
• Public Route Table associated with both public subnets
• Internet Gateway attached

Purpose: Multi-AZ setup ensures high availability.

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🔹 Step 2 — Create Security Groups

1. ALB Security Group
   • Inbound: HTTP (80) from anywhere
2. EC2 Security Group
   • Inbound: HTTP (80) only from ALB SG
   • More secure approach: no public access to EC2

Purpose: Enforces least-privilege traffic flow.

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🔹 Step 3 — Create an EC2 Instance

• Amazon Linux / Ubuntu instance
• EC2 SG attached
• User Data used to install Apache + custom HTML:

#!/bin/bash
sudo apt update -y
sudo apt install apache2 -y
echo "<h1>Welcome to my Auto Scaling Project</h1>" > /var/www/html/index.html
sudo systemctl start apache2
sudo systemctl enable apache2

Result: A running web server in your custom VPC.

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🔹 Step 4 — Create AMI (Golden Image)

• A custom AMI created from the EC2 instance
• This AMI contains pre-installed Apache + app files

Purpose: Enables fast, consistent, identical environment deployment.

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🔹 Step 5 — Create Launch Template

• Launch Template created using:
  • Custom AMI
  • Instance type
  • EC2 Security Group
  • User data (optional, since AMI already configured)

Purpose: ASG uses this template to create new instances automatically.

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🔹 Step 6 — Create Target Group

• Target type: Instances
• Health check: / on port 80
• Will dynamically register EC2 instances launched by ASG

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🔹 Step 7 — Create Application Load Balancer

• ALB created in both public subnets
• Listener: HTTP (80)
• Target Group attached

Result: ALB distributes traffic across all healthy EC2s.

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🔹 Step 8 — Create Auto Scaling Group (ASG)

• ASG configured using Launch Template
• VPC Subnets: Both public subnets
• Desired capacity: 1
• Min: 1, Max: 2
• Health checks: ELB
• Automatically registers instances to Target Group

Outcome:

• If traffic increases → ASG scales out
• If instance fails → ASG replaces it
• If load decreases → ASG scales in

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🏆 4. Skills Demonstrated (Interview-Focused)

✅ Core AWS Skills

• VPC design
• Multi-AZ architecture
• Security Group modeling
• EC2 provisioning
• Application Load Balancer
• Auto Scaling Group
• Launch Templates
• AMI lifecycle

✅ Production Concepts

• High Availability (HA)
• Auto Healing
• Horizontal Scaling
• Elastic Load Balancing
• Golden Image pattern
• Infrastructure segmentation

✅ DevOps Strength

• Clear understanding of cloud infrastructure
• Ability to design scalable systems
• Knowledge of traffic flow & security boundaries
• Understanding of stateless architecture

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🎯 5. Real-World Use Cases

• High traffic websites
• Auto scaling web apps
• Disaster recovery setups
• Fault-tolerant systems
• Production-grade backend servers

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🚀 6. Future Enhancements

• Infrastructure as Code (Terraform)
• Configuration Management (Ansible)
• CI/CD with Jenkins + GitHub Actions
• Containerization (Docker & Kubernetes)
• ALB + ASG + RDS multi-tier architecture

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👨‍💻 Author

Ramkumar Baghel
Cloud & DevOps Enthusiast | AWS | Terraform | Linux | Docker | CI/CD

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