Redirecting Non-www to Domain Equivalent

A question came up on a blog post of mine on how to redirect a domain name that doesn’t have www in it while retaining the original domain name.  Basically, to have a generic redirect to add on a www if it’s not already there.

For example, how could you have something.com always redirect to www.something.com where something could be any of a number of domain names that you manage.

This is fully possible with URL Rewrite.  Here’s what the config looks like.  If you want a full walkthrough using the setup wizard then refer to my previous post for the details.

<rule name="non-www to www" enabled="true" stopProcessing="true">
 <match url=".*" />
 
<conditions>
 <add input="{HTTP_HOST}" pattern="^[^\.]+\.[^\.]+$" />
 
</conditions>
 <action type="Redirect" url="http://www.{HTTP_HOST}/{R:0}" />
</rule>

This rule watches for all 2 level domains and redirects to the same domain name and tacks on the www to the beginning.  So something.domain.com won’t be redirected, but domain.com will.