Production Setup

I am on CentOS7 and am trying to run the script to install in production mode.
During install setup using automated I got nginx starting error.

I tried restarting nginx by issuing sudo service nginx restart but got an error.

On checking the logs I found the following:
[erpnext4@erpnext4new nginx]$ sudo tail /var/log/nginx/error.log
2015/06/10 10:44:07 [emerg] 14691#0: open() “/etc/nginx/conf.d/frappe.conf” failed (13: Permission denied) in /etc/nginx/nginx.conf:43

Could this be a permission issue or a firewall issue or am I missing something?