With WordPress 3.0 and above, you have the ability to create a network of sites by using the multisite feature. Multisite is a powerful WordPress feature that can be used by small, medium, and large websites.

It enables you to create multiple websites from single WordPress installation. This lets you turn your website into a network of websites. With WordPress you can create new sites instantly and manage them using the same username and password on the entire network of sites. You can also allow users to create a site on your network.

You can install multisite on sub-domain (site1.example.com) or sub-directory (example.com/site1). With this tutorial you will be able to install and create WordPress multisite network on a sub-directory. We recommend a sub-directory, as installing on sub-domain will require you to add a wild-card sub-domain on your hosting server, which is not allowed when you are using their basic shared hosting plan.

Before you begin you need to ask yourself two questions. First, why you need a multisite network. Second, how it will serve your purpose and objectives. As rolling back to single WordPress Installation will require lots of work.

Creating a multisite network can be useful for business that has different locations and branches. It can benefit government or non-profit organization  with different departments, locations, and regions. It can benefit you when you want to start a network of websites with different niches, or when you want to start networks of blogs for users, just like WordPress.com.

Five Steps to Install and Setup WordPress Multisite Network

Step 1: Backup and Deactivate Plugins

Before you begin backup all the files and database in case something goes wrong. Next deactivate all the plugins.

Step 2: Edit wp-config.php File

To enable network you must first define multisite in the wp-config.php file. For this open up wp-config.php and add this line “define( ‘WP_ALLOW_MULTISITE’, true );” above where it says /* That’s all, stop editing! Happy blogging. */. If it doesn’t say that anywhere, then add the line somewhere above the first line that begins with require or include:

/* Multisite */
define( 'WP_ALLOW_MULTISITE', true );

Once done refresh your browser.

Step 3: Network Installation

The previous step will enables a new menu is tools called Network Setup.

After that, you need to go to Tools » Network Setup and click on install.

Step 4: Enabling the Network

When you click on install, you will be redirected to page giving you two codes to be added to the wp-config.php and .htaccess file. To enable your network, follow the instructions on the Create a Network of WordPress Sites screen.

Once you complete these steps, your network is enabled and configured. You will have to log in again.

Step 5: Multisite Is Ready! Add New Site

After successfully setting up the Multisite Network. Click on Network Admin » Dashboard, You will notice that there are new menu items to manage your multisite network. You will also see a dashboard widget allowing you to create new site and users.