apache .htaccess实现301重定向

<IfModule mod_rewrite.c>
    Options +FollowSymlinks
    RewriteEngine On
    #301定向
    RewriteCond %{HTTP_HOST} ^aaa.cn [NC,OR]
    RewriteCond %{HTTP_HOST} ^www.aaa.cn [NC,OR]
    RewriteCond %{HTTP_HOST} ^bbb.com [NC]
    RewriteRule ^(.*)$ http://www.bbb.com/$ [L,R=]
</IfModule>

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