Как обработать 500 ошибку php-fpm из nginx?

server {
	listen 80;
	server_name example.com;
	set $path "/var/www";
	
	root $path/public;
	index index.html index.htm;
    
       
	error_page 500 502 503 504 /50x.html;
	location = /50x.html {
		root $path/system;
	}

	location = / {
		try_files @site @site;
	}
	location / {
		try_files $uri $uri/ @site;
	}

	location @site {
		fastcgi_pass unix:/var/run/php5-fpm.sock;   
		include fastcgi_params;
		fastcgi_param  SCRIPT_FILENAME $path/site/index.php;
	}
}