[quote="Igor Sysoev"]
server {
listen 80 default_server;
server_name "";
location / { return 404; }
root /usr/share/nginx/html;
error_page 404 /404.html;
location = /404.html { }
}
[/quote]
[emerg]: "default_server" parameter can be specified for the default "listen" directive only in /etc/nginx/conf.d/default.conf:2
configuration file /etc/nginx/nginx.conf test failed

ps: nginx version: nginx/0.7.67