DNS Configuration, SSL, and HTTP Setup

Setting up a secure, production-ready web application requires proper DNS configuration and SSL certificates. This guide walks through the steps to configure DNS, obtain SSL certificates, and set up HTTPS.

Understanding the Stack

• DNS: Translates domain names to IP addresses
• SSL/TLS: Encrypts data transmission
• HTTPS: Secure HTTP protocol

1. DNS Records Setup

Configure these records at your registrar (GoDaddy, Namecheap, Route53):

Type: A
Name: @
Value: your-ec2-public-ip

Type: CNAME
Name: www
Value: yourdomain.com

2. Installing Certbot

sudo apt update
sudo apt install certbot python3-certbot-nginx -y

3. Obtaining SSL Certificates

Certbot can automatically configure Nginx for you:

sudo certbot --nginx -d yourdomain.com -d www.yourdomain.com

Follow the prompts to redirect HTTP to HTTPS (recommended).

4. Automatic Renewal

Let's Encrypt certs expire in 90 days. Verify the auto-renewal timer:

sudo systemctl status certbot.timer
sudo certbot renew --dry-run

5. Security Best Practices

Add these headers to your Nginx config for better security:

add_header X-Frame-Options "SAMEORIGIN" always;
add_header X-Content-Type-Options "nosniff" always;
add_header X-XSS-Protection "1; mode=block" always;

Verification

Visit your site at https://yourdomain.com and check for the padlock icon!