NGINX on EC2 not loading sites enabled - nginx

Question

I have deployed a Drupal site that was developed on DigitalOcean Ubuntu onto AWS EC2 Ubuntu. So essentially the directory structure and configuration files are copied from DigitalOcean VPS. But the site on DigitalOcean is accessible while that on AWS throws a ERR_CONNECTION_REFUSED error on the browser.
I have beenn trying for several hours and haven't found any reason why the AWS site doesn't load. There are no error and access log messages in /var/log/nginx
My /etc/nginx/nginx.conf has the following line so I am sure the configuration files in /etc/nginx/sites-enabled folder are being read by Nginx.
include /etc/nginx/sites-enabled/*.*;
The /etc/nginx/sites-enabled has sym links to /etc/nginx/sites-available directory and the /etc/nginx/sites-available/domain.conf contains the following
server {
listen subdomain.domain.biz;
server_name subdomain.domain.biz;
root /home/sridhar/public_html/domain/public;
keepalive_timeout 70;
access_log /home/sridhar/public_html/domain/log/access.log;
error_log /home/sridhar/public_html/domain/log/error.log;
# Enable compression, this will help if you have for instance advagg ^ modue# by serving Gzip versions of the files.
gzip_static on;
index index.php;
#index index.php index.html index.htm;
location = /favicon.ico {
log_not_found off;
access_log off;
}
location = /robots.txt {
allow all;
log_not_found off;
access_log off;
}
location ~* \.(txt|log)$ {
allow 192.168.0.0/16;
deny all;
}
location ~ \..*/.*\.php$ {
return 403;
}
# No no for private
location ~ ^/sites/.*/private/ {
return 403;
}
location ~ (^|/)\. {
return 403;
}
location / {
try_files $uri $uri/ #rewrite;
expires max;
}
location #rewrite {
rewrite ^/(.*)$ /index.php?q=$1;
}
location ~ \.php$ {
fastcgi_split_path_info ^(.+\.php)(/.+)$;
#NOTE: You should have "cgi.fix_pathinfo = 0;" in php.ini
include fastcgi_params;
fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
fastcgi_intercept_errors on;
#fastcgi_pass unix:/tmp/phpfpm.sock;
fastcgi_pass 127.0.0.1:9000;
}
location ~ ^/sites/.*/files/styles/ {
try_files $uri $uri/ #rewrite;
}
location ~* \.(js|css|png|jpg|jpeg|gif|ico)$ {
expires max;
log_not_found off;
}
}
Is there any specific configuration that needs to be cariied out for AWS EC2? Or have I missed something.