How can I redirect any ServerAlias to the respective ServerName?

Question

I want to 301 redirect all example.org to www.example.org. The following example is doing just that, but it's got a lot of noise to it and is thus hard to maintain and error prone:

<VirtualHost 192.0.2.123:80>
        ServerName      example.org
        RedirectPermanent       /               http://www.example.org
</VirtualHost>
<VirtualHost 192.0.2.123:80>
        ServerName      www.example.org
        DocumentRoot    /usr/local/www/example
</VirtualHost>

Do you happen to know if there's some shorter version for the whole thing above?

Something like this pseudo-config:

<VirtualHost 192.0.2.123:80>
        ServerName      www.example.org
        ServerAlias     example.org
#       Redirect-Every-ServerAlias-To-ServerName
        DocumentRoot    /usr/local/www/example
</VirtualHost>

So that way I would just need to provide every subdomain that should be redirected under ServerAlias ?

Answer 1

Use mod_rewrite, something like this:

RewriteEngine On
RewriteCond %{HTTP_HOST}  !^www.example.org [nocase]
RewriteRule ^(.*)$        http://www.example.org$1 [last,redirect=301]

Answer 2

<VirtualHost *:80>
    ServerName www.example.org
    DocumentRoot /usr/local/www/example
</VirtualHost>

<VirtualHost *:80>
    ServerName example.org
    ServerAlias *.example.org another.org *.another.org
    Redirect 301 / http://www.example.org/
</VirtualHost>

make sure to put them in the right order, www first