//试试手气
add_action('init','random');
function random() {
	if( isset( $_GET['random'] ) ){
		global $wpdb;
		nocache_headers();//禁止浏览器缓存
		$posts = get_posts('post_type=post&orderby=rand&numberposts=1');
		foreach($posts as $post) {
			$link = get_permalink($post);
		}
		wp_redirect($link,307);//307 临时跳转
		exit;
	}
}