show different pages for different Ips

nginx.conf

server {
    listen  8888;
    server_name fw.dev 127.0.0.1;
    root /var/www/html/fwdev;

    error_page 403 http://www.example.com;

    allow 127.0.0.1;
    deny all;

    location / {
        index index.php index.html;
    }

    location ~ \.php$ {
        fastcgi_pass   127.0.0.1:9000;
        fastcgi_index  index.php;
        fastcgi_param  SCRIPT_FILENAME $document_root$fastcgi_script_name;
        include        fastcgi_params;
    }
}