IIS: Multiple domains for one site

Question

I've a site which can be acceded through multiple domains (ie mydomain.com, mydomain.com.ar, mydomain.net, etc). Right now I have in the IIS one site and in the properties I added each domain as a host header values (the identities of the Web Site).

All domains work great. Also I have a root in the web site which checks if its a mobile client and some other stuff which redirects to the home page in the domain that I want as "default". So if the client types mydomain.com or mydomain.net it will end in the domain I want. But when the client types mydomain.com/HomePage (or any other page) it wont access the root, so it wont be redirected and will end in the domain it type.

I am doing some changes in this server so I'd like to take advantage of this changes to fix this little annoying issue. How do you recommend to manage the multiple domain for the same site? My (very elemental) acknowledge of SEO tells me that its better to use one domain and all the others redirect (somehow) to the "main" / "default" one.

Update When I asked the question I forgot that there is not one only site (despite all my explanation), there are a bunch of sites using sub-domains, folders, etc. So it is not just one asp.net site. I need an IIS solution.

Answer 1

If it is a asp.net application you can install URL Rewrite http://www.iis.net/download/urlrewrite and use the web.config file to specify the redirect

<system.webServer>
 <rewrite>
  <rules>
   <rule name="Redirect to WWW" stopProcessing="true">  
<match url=".*" />  
 <conditions>  
  <add input="{HTTP_HOST}" pattern="^domainname.com$" />  <!-- here you can use the from domain -->
 </conditions>  
 <action type="Redirect" url="http://www.newdomainname.com/{R:0}" />  
</rule> 
  </rules>
 </rewrite>
</system.webServer>

Hope this helps