linux主机如何设置404.301呢

.htaccess 文件创建如下内容

ErrorDocument 404 /404.php
RewriteEngine On
RewriteCond %{HTTP_HOST} ^52phpweb.com [NC]
RewriteRule ^(.*)$ http://www.52phpweb.com/$1 [L,R=301]

404.php 如下代码