A typical /opt/nginx/conf/nginx.conf file

nginx.conf

worker_processes  1;
events {
    worker_connections  1024;
}
http {
    passenger_root /home/appuser/.rvm/gems/ruby-1.9.2-p290@rails3010/gems/passenger-3.0.9;
    passenger_ruby /home/appuser/.rvm/wrappers/ruby-1.9.2-p290@rails3010/ruby;
    include       mime.types;
    default_type  application/octet-stream;
    keepalive_timeout  65;
    gzip  on;
    server {
        listen       80;
        server_name  www.YOUR_DOMAIN_HERE.com;
        root PATH_TO_YOUR_RAILS_APP_ROOT/public; 
        passenger_enabled on;
        passenger_use_global_queue on;
    }
}