What is WordPress Multisite?

WordPress Multisite is a highly popular WordPress feature that allows you to create and manage multiple websites using a single installation on your server.. In practice, it allows you to manage multiple WordPress sites through a single dashboard, significantly simplifying management and maintenance operations.

Despite this, it's often not immediately clear how and when to use this feature correctly. For this reason, this guide aims to clarify the main questions: what is WordPress Multisite, who should use it, and how to configure it correctly.

So let's start with the basics.

1. What is WordPress Multisite?

WordPress Multisite is a built-in feature that allows you to create, manage, and run multiple WordPress websites from a single installation and administration dashboard. It essentially allows you to control a network of sites through a single control panel, greatly simplifying day-to-day operations. This feature was previously known as WordPress Multi-User, or simply WPMU, before being officially incorporated into the WordPress core.

WordPress Multisite is not a recent innovation: it is an advanced feature of the platform that has existed since the release of WordPress 3.0, and over time it has become a stable and widely used solution. With Multisite, you can centrally manage multiple sites, such as making one-click updates to all sites in your network, or managing a platform where users can create their own sites within your Multisite network. This approach allows you to maintain control from a single interface, reducing management complexity and making the administration of multiple WordPress installations more efficient.

2. Main Features Of WordPress Multisite

WordPress Multisite comes with various unique features. For starters, you can run a network of blogs and websites from a single WordPress installation. It allows you to create a network of subdomains, such as https://john.example.com, or directories, such as https://www.example.com/john/. Alternatively, you can also have a separate domain for every website on the network. It's also easier to replicate functionality across a network of websites.

In WordPress Multisite, you can control the entire network as a Super Admin. As a normal website administrator, you can only control one website on the network. As a Super Admin, you control the accessibility of users who want to create an account and set up their own WordPress blogs or websites.

A Super Admin can install new themes and plug-ins, make them available to websites in the network and also customize themes for all websites. Another feature is the ability to create websites and online stores targeting languages, regions and specific currencies.

Both Super Admin and Website Admin can control the contents. Although this control extends to the entire network for a Super Admin, the website administrator has the right to choose which content from the root domain is displayed on the respective website. Plugins are also under the control of a Super Admin. However, a website administrator can activate and deactivate plug-ins on their website as needed.

3. Who Should And Who Shouldn't Use WordPress Multisite?

While WordPress Multisite offers several interesting features, it's not always the best choice for every scenario. The main consideration is that all websites within a Multisite network share the same database. In other words, the sites aren't completely independent from each other in terms of data, which leads to some operational limitations. For example, it's not possible to easily back up a single site in isolation from the others. For this very reason, all websites in the network should belong to the same primary domain or be part of the same organizational plan.

To better clarify the concept, let's imagine the case of a university. A university could use WordPress Multisite to create and manage multiple websites: one for each department, one for student and faculty blogs, and perhaps others for forums or information areas. Because all these sites would share the same database and be linked to the university's main domain, they would be much easier to administer through a single Multisite network, with centralized and consistent management.

Likewise, businesses such as banks and financial institutions with a national or global branch network, digital publications divided into multiple content sections, government offices with multiple departments, hotel chains, multi-store stores, e-commerce companies, or website design companies like Wix could also benefit from using a Multisite network, precisely because all the sites are part of a single ecosystem and share a common structure.

Conversely, a web designer or agency should not use WordPress Multisite to manage unrelated client projects. For example, if one of your clients decides to move their website to another hosting provider or infrastructure in the future, complications could arise, as that site would share the database with other sites on the network. Furthermore, as mentioned, Multisite makes it difficult to back up a single site independently. In such situations, it's generally preferable to use separate WordPress installations, keeping each project completely independent and easier to manage individually.

4. Pros And Cons Of WordPress Multisite

Now that we know who should and shouldn't be using WordPress Multisite, let's look at the technical pros and cons. You will need to weigh them carefully before making a decision.

Pro

• The main benefit is the ability to manage multiple websites from a single dashboard. This is useful if you run multiple websites managed by different teams under one main domain, such as an e-commerce store with several country-specific subsites.
• However, you can also assign a different administrator to each website on your network.
• With a single download, you can install and activate plugins and themes for all websites in your network.
• You can also manage updates with one master install for all websites in your network.

Cons

• Since all websites share the same network resources, they will all go down if the network goes down.
• A sudden increase in traffic to one website will affect all others on the network. Unfortunately, beginners often find it difficult to manage server traffic and resources on a Multisite network.
• Similarly, if one website is hacked, the entire network will be compromised.
• Not all WordPress plugins support a Multisite network.
• Similarly, not all web hosting providers have the necessary tools to support a multisite network.
• If your hosting provider does not have the server requirements, you will not be able to use the Multisite feature. For example, some hosting providers may not allow you to add a domain to the same hosting server. In that case, you may need to change or upgrade your hosting plan or switch providers.

5. Requirements For WordPress Multisite

Once you've understood the technical pros and cons, you should have already decided whether WordPress Multisite is the right option for your needs. If you plan to use it, it's important to know that you'll first need to meet some basic technical requirements, which are necessary to ensure the network runs smoothly, stably, and efficiently.

One of the first things to consider is your web hosting provider. You'll need a hosting plan that can handle multiple domains. While shared hosting is theoretically possible for a very small network, consisting of a couple of websites with low traffic, in practice, VPS hosting or a dedicated server is strongly recommended. This is because, by its very nature, a WordPress Multisite network concentrates multiple sites on a single installation, requiring more resources and requiring more complex management than a single site.

In this context, the best solution is to rely on a hosting provider that uses NGINX combined with Varnish, so as to be able to efficiently handle a high number of requests and guarantee excellent overall performance. This combination is particularly suitable for multisite scenarios due to the benefits in terms of web performance, reduced response times and better load management.

You'll also need to have at least a basic understanding of how to install WordPress. If you already have a working WordPress installation, this is certainly an advantage, but before proceeding, it's essential to perform a complete backup of your site. Likewise, you'll need to temporarily deactivate all plugins to avoid conflicts or issues when enabling Multisite mode.

It's equally important to ensure you have FTP access to the server, as you'll need to be able to edit some files. Therefore, some familiarity with editing files via FTP is also required. Finally, you'll need to enable "nice permalinks." In practice, your site's URLs shouldn't have a structure like this: https://example.com/?p=2345, but a more readable and clean form as https://example.com/my-page, which is a fundamental requirement for the correct functioning of WordPress Multisite.

6. Multisite Domain Mapping

By default, when you create new sites within a WordPress Multisite network, they are created as subdomains or subfolders of the main site. In practice, the structure can take the form of:

subsite.network.com

or:

network.com/subsite

This means that, logically, all sites are part of the same WordPress installation and are organized under the main domain of the network.Technically, WordPress uses this structure to differentiate between different sites, while maintaining a single codebase and a single shared database.

However, this approach isn't always desirable. In many cases, you may want to assign each site a completely independent domain name, such as domain.com, with no visible reference to the network's main domain. This is where domain mapping comes in.

Domain mapping allows you to associate an external domain with a specific site in the Multisite network, allowing that site to be displayed publicly under its own dedicated domain. In other words, even though internally the site continues to exist as:

subsite.network.com

o:

network.com/subsite

To the outside it may simply look like this:

domain.com

From a practical point of view, the result is that:

subsite.network.com = domain.com

or:

network.com/subsite = domain.com

This mechanism allows you to maintain all the centralized management typical of Multisite, but at the same time gives each site its own identity, completely separate at the domain level, which is essential in many professional or organizational contexts.

Historically, before WordPress 4.5, this required a dedicated domain mapping plugin. The feature wasn't integrated into the core WordPress site and required external solutions to function properly. Starting with WordPress 4.5, domain mapping has become a built-in feature, making the process simpler, more stable, and better integrated with the WordPress Multisite architecture.

Today, therefore, domain mapping represents one of the key elements that makes WordPress Multisite extremely flexible: it allows you to combine the power of centralized management with the ability to present each site as an autonomous project, at least from the point of view of URL and public identity.

7. Multisite Hosting AND SSL

As you probably know, Secure Sockets Layer (SSL) allows you to transport data over the Internet securely. The data remains indecipherable for malicious users, bots and hackers.

However, some hosting providers offer free SSL certification only for the primary domain. You may need to purchase it separately for each subdomain. If one of the websites on your Multisite network does not have SSL certification, this will compromise the security of all other websites. Therefore, make sure that all websites on your WordPress Multisite network have SSL certificates.

Our company is able to supply WordPress Multisite Hosting without any limits inherent to the HTTPS and SSL configuration, both with free certificates such as Let's Encrypt and with commercially verified ones such as RapidSSL.

8. Installing And Configuring WordPress Multisite For New And Existing Websites

To get started, you'll need a working WordPress installation. If you're starting from scratch, the first step will be to install WordPress on your server as you normally would for a single site. Once the installation is complete, you can proceed with enabling the Multisite feature. Alternatively, you can also enable Multisite on an existing WordPress site, turning it into a network of sites.

Before doing so, however, it's essential to perform a complete backup of your website. This step is essential because enabling Multisite involves structural changes to your WordPress configuration, and having a backup will allow you to quickly restore your previous state in the event of a problem.

Once the backup is complete, you'll need to access your site's files using an FTP client or the file manager provided by your control panel, such as cPanel. Then, locate the file wp-config.php in the root directory of your WordPress installation and open it in Edit. This file contains your site's main configuration settings, and it's here where you'll need to enable Multisite support.

Inside the file wp-config.php, add the following code just before the line containing the comment /* preceding “That's all, stop editing!” or something similar:

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

After inserting this line, save the file and upload it back to your server, overwriting the existing one. At this point, the Multisite feature has been enabled at the configuration level, but it's not fully active yet: you've simply unlocked the ability to set up a network of sites within WordPress.

The next step is to configure the Multisite network. If you're already logged into your WordPress dashboard, simply refresh the page to see the new network options appear. Otherwise, you will need to log in to the admin panel again.

From here, WordPress will guide you through the steps necessary to complete the network setup, allowing you to define the site structure (e.g., subdomains or subfolders) and applying any additional changes to the configuration files. Once this process is complete, your WordPress installation will be officially transformed into a Multisite network, ready to host multiple sites managed from a single central dashboard.

This way, whether you're starting from a fresh installation or converting an existing site, the process remains conceptually the same: enable Multisite support, configure your network, and complete the steps WordPress requires to get the new structure up and running.

Concluding

As you can see, WordPress Multisite has several advantages. You can control and manage different websites from a single dashboard. It can certainly reduce the legwork and make tracking your website hassle-free. Hopefully, you now have enough knowledge about installing, troubleshooting, and working with applications on a Multisite network to take the plunge.

Work with a WordPress consultant expert of multisite

We recommend working with a WordPress consultant who is experienced in scaling WordPress Multisite. As your multisite network grows, you'll need to keep an eye on the number of server resources your site is using, as well as the maintenance of your database. It's perfectly manageable as long as you're proactive, and it helps to work with an expert who can guide you through the growth phase of your Multisite.

Choose a good hosting provider that is experienced in multisites

For WordPress Multisite, it is also important to use a great WordPress hosting provider that already supports the various features of Multisite and your specific type of Multisite. At Pressable, for example, we host some large subdirectory URL Multisite networks and have developed technologies and practices to ensure that our Multisite Subdirectory deployments run smoothly and efficiently. A hosting provider with great experience hosting Multisite deployments will greatly increase the likelihood of continued success for your projects.

We hope this information makes it easier for you to determine if Multisite is right for you. If you have questions about your specific Multisite setup, we'd be happy to help. Contact our account team with your questions.