Nginx Enable Options rquest, restart nginx
sudo /etc/init.d/nginx restart
/etc/nginx/includes/external/server-common.conf
location /robots.txt {
try_files /sites/default/files/robots.txt $uri;
}
/etc/nginx/includes/external/server-common.conf
if ($request_method !~ ^(GET|HEAD|POST|OPTIONS)$ ) {
....
}