EC2 Mutliple Instance for the same app with Load Balancing

ec2-load-balance

```
server {
    listen 80;
    server_name SUB_DOMAIN.DOMAIN.com;
    return 301 https://$host$request_uri;
}


upstream backend {
    server EC2_Private_IPv4:APP_PORT;  # In-house test server
    server EC2_Private_IPv4:APP_PORT;  # In-house test server
    server EC2_Private_IPv4:APP_PORT;  # In-house test server
    server EC2_Private_IPv4:APP_PORT;  # EC2 production server
}


server {
    listen 443 ssl;

    server_name api.sudhamrit.org;
    ssl_certificate /etc/letsencrypt/live/SUB_DOMAIN.DOMAIN.com/fullchain.pem; # managed by Certbot
    ssl_certificate_key /etc/letsencrypt/live/SUB_DOMAIN.DOMAIN.com/privkey.pem; # managed by Certbot

    client_max_body_size 20M; # Adjust this to fit your needs. Note the 'M' immediately follows the number.	
	
    ssl_protocols TLSv1 TLSv1.1 TLSv1.2;
    ssl_prefer_server_ciphers on;
    ssl_ciphers 'EECDH+AESGCM:EDH+AESGCM:AES256+EECDH:AES256+EDH';

    location / {
        proxy_pass http://backend;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection 'upgrade';
        proxy_set_header Host $host;
        proxy_cache_bypass $http_upgrade;
    }
}
```