Multi-site or Network is the most talked about new feature in WordPress 3.0 – the WordPress team has folded the functionality of WordPress Multi User into the main WordPress project. So how do you use it and what can you use it for? With multi-site you have the option to set up several WordPress instances using the same installation. These WordPress instances really are separate site that for example can have different themes. This could be useful for many different purposes like for setting up a member area behind a blog that you want to style differently, creating different product sites / landing pages, for testing out ideas and themes etc. Internet Marketers have also used WordPress MU for some time creating mini-nets to boost the number of inbound links to “keyword sites” and opt-in/sales pages. In the future a plain WordPress will do the job. By default this feature is disabled in WordPress 3.0. If you want to use it, you would have to enable it. Let’s see how it is done.
This tutorial assumes you are comfortable using FTP clients such as Filezilla and doing basic edits of WordPress files.
1. Download WordPress 3.0. You can find it http://wordpress.org/download/.
2. Edit wp-config in your favorite text editor and add the following line:
(I’d suggest adding it just above the line “// ** MySQL settings – You can get this info from your web host ** //”)
3. Install WordPress normally
NOTE: If you’ve already installed WordPress 3.0, just edit wp-config and add that line of code, there’s no need to re-install.
4. Under Tools on the sidebar, you’ll now have an “Network” option. Click it.
5. Here you’ll setup your “Network” – a Network is all the blogs or sites you’ll have under your WordPress install (if you’re migrating back to WordPress from WordPress Multi User this might be confusing. In WordPress Multi User the term for network was “site” and the term for site was “blog.” Explanation here).
If your host supports it, you’ll have the option here to choose between subdomains and subdirectories.
Example of a subdomain: site1.yourdomain.com
Example of a subdirectory: yourdomain.com/site1
Fill out your Network Title and Admin E-mail Address and press install.
6. You’ll be greeted with your next list of steps: creating a blogs.dir directory, editing wp-config.php, and .htaccess. WP recommends, as do I, backing up wp-config.php and .htaccess files before proceeding.
After completing the steps, you’ll need to log back into WordPress.
7. On your next login, you’ll notice a new menu: “Super Admin.”
8. Click “Sites” under this option to create a new site. Fill out the forms accordingly.
9. After creating a new site, click Users. You’ll see a new user was created for the new site.
10. You can control all sites on your network through the Super Admin menu, but you might also find it easier to administer individual sites through their own admin menus. You can access them as you would for a normal wordpress site. On the Add Sites above (step 8), it would be the Site Address you choose: http://mydomain.net/[Site Address]/wp-admin
Create A Network @codex.wordpress.org
How to enable Multi-Site option in WordPress 3.0 @wpbeginner.com