EC2_Nginx_Setup.md

🚀 EC2 Nginx Setup — From Zero to Live Server

This project documents the end-to-end setup of an AWS EC2 instance and deploying a basic web server (Nginx) accessible over the internet.

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📌 Objective

• Launch an EC2 instance
• Connect via SSH using a key pair
• Install and run Nginx
• Expose the server via Public IP
• Debug common connection issues

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🏗️ Architecture

User (Browser)
↓
Public Internet
↓
Internet Gateway (IGW)
↓
VPC
↓
Public Subnet
↓
EC2 Instance (Amazon Linux 2023)
↓
Nginx (Port 80)

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⚙️ Step 1 — Launch EC2

• AMI: Amazon Linux 2023
• Instance Type: t2.micro (Free tier)
• Key Pair: .pem file (download and store securely)
• Network:
  • Public Subnet
  • Auto-assign Public IP: Enabled

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🔐 Step 2 — Connect via SSH

❌ Common mistake

ssh -i aws_ssh.pem ec2_user@http://<PUBLIC_IP>/

✅ Correct command

chmod 400 aws_ssh.pem
ssh -i aws_ssh.pem ec2-user@<PUBLIC_IP>

🔍 Notes

• Username depends on AMI:
  • Amazon Linux → ec2-user
• .pem must have strict permissions (400)

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🌐 Step 3 — Initial Issue

Problem:

ERR_CONNECTION_REFUSED

Root Cause:

• EC2 is running
• But no application is listening on port 80

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🧠 Understanding the Issue

EC2 is just a virtual machine, not a web server.

Request → EC2 → OS → Port 80 → ❌ No service → Connection refused

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📦 Step 4 — Install Nginx

sudo yum update -y
sudo yum install nginx -y

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▶️ Step 5 — Start Nginx

sudo systemctl start nginx
sudo systemctl enable nginx

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✅ Step 6 — Verify

sudo systemctl status nginx

Check listening ports:

sudo netstat -tulnp | grep 80

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🌍 Step 7 — Access Application

Open in browser:

http://<PUBLIC_IP>

You should see:

Welcome to nginx!

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💾 Disk Check (Verification)

df -h

Example output:

• Root volume: /dev/xvda1
• Size: 8GB
• Used: ~25%

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🔒 Security Configuration

Security Group Inbound Rules

Type	Port	Source
SSH	22	0.0.0.0/0
HTTP	80	0.0.0.0/0

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⚠️ Common Errors & Fixes

Issue	Cause	Fix
Permission denied (publickey)	Wrong username or key	Use ec2-user, correct .pem
Connection refused	No app running	Install/start Nginx
Timeout	Port blocked	Check Security Group
SSH fails	Wrong permissions	chmod 400 key.pem

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💸 Cost Considerations

• EC2 billed per second (t2.micro is low cost)
• Idle instance = unnecessary cost
• Data transfer out may incur charges
• Stop instance when not in use:

aws ec2 stop-instances --instance-ids <id>

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🔐 Security Best Practices

• Never expose SSH (22) to 0.0.0.0/0 in production
• Use:
  • Bastion host OR
  • AWS SSM Session Manager
• Store .pem securely (never commit to GitHub)
• Use IAM roles instead of hardcoded credentials

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🧠 Key Learnings

• EC2 ≠ Web Server
• Public IP only routes traffic — it doesn't serve content
• You must run a process (Nginx / Node.js / etc.)
• SSH issues are usually:
  • Wrong user
  • Wrong key
  • Wrong permissions

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🚀 Next Steps

• Deploy a Node.js app instead of Nginx
• Use Docker on EC2
• Set up an Application Load Balancer (ALB)
• Add HTTPS using ACM + Nginx
• Automate using Terraform

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📸 Screenshots

EC2 Instance Launch Success

SSH Login to EC2

Nginx Installation

Nginx Service Started and Enabled

Nginx Welcome Page

Git, Docker, and Disk Check

Disk Usage Verification

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🏁 Conclusion

You successfully:

• Launched a cloud server
• Connected securely via SSH
• Installed and ran a web server
• Exposed it to the internet

This is your first real production-like system.

Next step: make it scalable.