Nginx error log empty

Quote from fulltilt

I'm just testing some fail2ban rules and noted that /var/log/nginx/error.log is always empty, access log is working fine.

As per nginx.nginx, only critical errors are loggued. If you want raise the error level, you must tune the configuration file, preferably using an i-MSCP listener file to ensure persistence on i-MSCP upgrade/reconfiguration.

See also: http://nginx.org/en/docs/ngx_core_module.html#error_log