How to Set Up a WordPress Multisite Network and Use an Astra Child Theme

WordPress Multisite lets you create and manage a network of websites from a single WordPress dashboard.

This makes it easy to update themes and plugins for all your sites at once. A network can have just two sites or thousands. In fact, WordPress.com runs on Multisite.

Before you begin, make sure the Astra theme is already installed on your site and that you have access to your site files (through your hosting File Manager, FTP, or a file manager plugin).

What is a Child Theme?

A child theme is a small add-on theme that inherits all the features and styles of its parent theme (in this case, Astra). You use a child theme when you want to customize theme files safely.

If you edit Astra’s files directly, your changes will be lost the next time Astra updates. When you add your custom code to a child theme instead, your changes stay safe after every update.

To learn more, read our guide on what a child theme is and how to install it for Astra.

User Roles

Super Admin (Network Administrator): When you enable Multisite, you become the Super Admin. You can manage every site, theme, plugin, and user in the network. If you allow it, other users can also create their own sites and become Administrators of those sites.

Site Administrator: These users manage a single site in your network. They cannot install new themes or plugins. They can only use themes the Super Admin has network enabled, and they can activate plugins only if the Super Admin allows it in Network Settings > Enable administration menus.

Site Administrators can add users to their own site and assign them roles, but they have no access to other sites in the network.

Domain Name

When setting up Multisite, you choose how the sites in your network will be addressed:
Sub-domains: site1.example.com
Sub-directories: example.com/site1

Please choose carefully, as this setting is difficult to change later. Sub-domains require wildcard DNS from your hosting provider. Also, if your WordPress site is more than a month old, WordPress may only allow the sub-domain option.

You can also give any site in your network its own custom domain (for example, mybakery.com) using domain mapping.

How to Set Up and Activate Multisite

Follow the steps below to enable Multisite on your WordPress installation. Once your network is ready, you’ll add the Astra child theme to it.

Take a full backup of your website (files and database) before enabling Multisite. Here’s how to back up your website.

Activating Multisite Feature

Multisite is built into every WordPress installation. You just need to turn it on.

Step 1: Install a File Manager Plugin

To turn on Multisite, you need to edit a file called wp-config.php. You can do this using your hosting File Manager (such as cPanel), an FTP client, or a file manager plugin.

In this guide, we’ll use the free File Manager plugin. Go to Plugins > Add New, search for “File Manager,” then click Install Now and Activate.

Step 2: Edit the wp-config.php File

Open the File Manager plugin, find the wp-config.php file in your main WordPress folder, right-click it, and select Code Editor.

Copy the code below and paste it just above the line that says /* That's all, stop editing! Happy publishing. */. Then click Save & Close.

define( 'WP_ALLOW_MULTISITE', true );

Multisite is now enabled. Next, let’s set up your network.

Setting Up a Multisite Network

Step 3: Deactivate All Plugins

If you’re enabling Multisite on an existing website, you need to deactivate all your plugins first. (Don’t worry, you can reactivate them afterward.).
Go to Plugins > Installed Plugins, check the box at the top to select all plugins, choose Deactivate from the Bulk actions dropdown, and click Apply.

Step 4: Run the Network Setup

Go to Tools > Network Setup.

Choose Sub-domains or Sub-directories (if available), enter a Network Title, and confirm your Network Admin Email. Then click Install.

WordPress will now show two code snippets. Add the first one to your wp-config.php file and the second one to your .htaccess file, replacing the existing WordPress rules in it.

Edit both files the same way you did in Step 2, using the File Manager plugin.

Once you’ve saved both files, WordPress will log you out. Simply log in again to access your new network.

Step 5: Open the Network Admin Dashboard

In the top admin bar, hover over My Sites > Network Admin and click Dashboard.

Here you’ll see the Right Now box, where you can create new sites and users or search for existing ones.

Step 6: Configure Network Settings

Go to Settings > Network Settings.

The most important section here is Registration Settings. By default, new user and site registrations are turned off.

You can allow new users to register, allow logged-in users to create new sites, or allow both.

On this page you can also enable the Plugins menu for site administrators under Enable administration menus. Click Save Changes when you’re done.

Creating a New Site

Go to Sites > Add New (or click Create a New Site on the Network Dashboard).

You will need to enter the following information to create a new site.

• Site Address (URL): The address of your new site. For example, if you chose sub-domains, entering “storyteller” creates storyteller.example.com.

• Site Title: The name of your new site. You can change it later.

• Site Language: The default language for the site. Choose a different one from the dropdown if needed.

• Admin Email: The email of the person who will manage this site. If the email doesn’t belong to an existing user, WordPress will create a new user and send them login details.

Click Add Site. To view all sites in your network, go to Sites > All Sites.

Adding Themes to the Multisite

Go to My Sites > Network Admin > Themes. Here you’ll see every theme installed on your network. Click Network Enable under a theme to make it available to all sites in the network.

To make a theme unavailable again, click Network Disable. This option only appears for themes that are already network enabled.

To install a new theme, click Add New at the top, find the theme, and click Install.

Important: Only the Super Admin can install themes. Individual site administrators can only activate themes that you have network enabled.

Using Astra Child Theme

First, make sure the Astra parent theme is installed on your network. Then create your child theme using the free Astra Child Theme Generator.
Go to Network Admin > Themes > Add New > Upload Theme, choose your child theme’s .zip file, and click Install Now.
Click Network Enable on the child theme. Each site administrator can now go to Appearance > Themes on their site and activate it.

Tip: If you want different child themes for different sites, give each one a unique name when generating it. If two child themes have the same name, WordPress will ask to replace the existing one when you upload the second.

Installing Plugins to the Multisite

To manage plugins, go to My Sites > Network Admin > Plugins.

To install a new plugin, click Add New, find the plugin, and click Install Now. Then choose one of these:

Network Activate: The plugin runs on every site in your network, and site admins can’t deactivate it.
Leave it installed only: Site admins can activate it on their own site (if you’ve enabled the Plugins menu for them).

Remember to reactivate the plugins you deactivated in Step 3.

That’s it! Your multisite network is ready, and you can now use your Astra child theme across your sites. If you run into any issues, our support team is happy to help.