[cheatsheets] nginx

ALB & Nginx proxying

1. Open the Nginx configuration file:

Copysudo vi /etc/nginx/nginx.conf

1. Modify the configuration to listen on port 80 and proxy to your application on port 8080:

nginxCopyhttp {
    # ... (keep existing http block contents)

    server {
        listen 80;
        server_name _;  # This will respond to any server name

        location / {
            proxy_pass http://localhost:8080;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
            proxy_set_header X-Forwarded-Proto $http_x_forwarded_proto;
        }
    }
}

1. Save and exit the editor.

2. Test the Nginx configuration:

Copysudo nginx -t

1. If the test is successful, restart Nginx:

Copysudo systemctl restart nginx

This configuration:

• Listens on port 80, which is typically where the ALB will forward traffic

• Proxies all requests to http://localhost:8080

• Sets appropriate headers, including X-Forwarded-Proto which the ALB uses to indicate whether the original request was HTTP or HTTPS

For your AWS setup:

1. Ensure your EC2 security group allows inbound traffic on port 80 from the ALB's security group.

2. In your ALB configuration:

   • Set up HTTPS listeners (port 443) with your SSL/TLS certificate

   • Configure rules to forward traffic to your EC2 instance(s) on port 80

   • Optionally, set up an HTTP to HTTPS redirect rule on the ALB

3. Make sure your application is actually running and listening on port 8080 on the EC2 instance.