Stephen Musgrave of Capellic, specializing in Drupal development and maintenance for non-profit, arts and progressive organizations, wrote an article regarding Drupal multi-sites on The Rackspace Cloud.
When searching for a cloud computing provider for his Drupal hosting, Drupal multi-site installations was a requirement – which The Rackspace Cloud does support. Stephen wrote a step by step article on how to gracefully set up Drupal multi-sites on The Rackspace Cloud.
Step by Step
1. Log in to to the Control Panel
2. Click on Hosting > Cloud Sites in the left sidebar.
3. Click on Add A Site button at the top of the Website List.
4. Select the client type the domain name into the popup and click on Add New Site button.
5. On the next screen, select the terms of the new domain name registration or select the last option, "Set up the website without registering the domain." Click on the Next Step button. (Of course, if you want to register the domain, you can do so. My instructions simply articulate my exact process.)
6. On the Select A Hosting Plan screen, in the Other Options section, select "Point to another website (alias)." Click on the Next Step button.
7. On the Find A Website To Point To page, select the deafult domain for your multi-site install. Click on the Next Step button.
8. After you are done reviewing your selects on the Review Your Selections page, click on the Finish button.
You will receive a confirmation message, "Successfully added website to account". Assuming your domain's ANAME is pointing to your IP address - or if you're using Mosso's DNS servers, you should see your new site when entering into your browser. If you see the default Drupal website, then you should verify that the new site's directory name (in the sites folder) matches your domain name. If not, simply change the directory name to match and you'll be fine. Keep in mind that "www" counts.