How to Activate WordPress Multi Site [Updated 2012]

WordPress multisite turns a website into a multiblogger machine like where one domain with one WordPress installation can be used to create up to millions of blogs on subdomains or subdirectories.

Multisite is hidden part of WordPress that has to be activated manually through a few edits to the site’s wp-config.php file.

There is no button in the site’s dashboard taht can be used to activate WP multisite. You will need FTP access to your server or a server control panel that lets you view and edit files stored on your server.

These instructions are easy to follow. You should have multisite activated in less than 10 minutes work.

Questions this guide answers

  • How do I activate WordPress multisite?
  • How do I make a wildcard subdomain in cPanel?
  • How do I send visitors to non existent blogs to my site’s homepage (or any other site or page)?
  • Can I use different domains for subdomain sites?

How to activate multisite

  • Disable all plugins. You can re-enable them after multi-site has been configured. Settings will return on reactivation.
  • Access the files on your server and browse to your domain’s root directory. Look for the file wp-config.php
  • Activate the multi-site features of WordPress by adding this line of code to the bottom of wp-config.php
    /** Enable or disable Worpress Multi-site features **/
    define('WP_ALLOW_MULTISITE', true);

    Put it just above the line that reads

    /* That's all, stop editing! Happy blogging. */
  • Refresh your WordPress dashboard then visit Tools>Network. You will see a screen that looks similar to the one in the picture below. Read onwards before you make any configuration changes.

BigBuz's WordPress 3.0 Multisite's Network Page

If you want to install your additional blogs on virtual sub-domains instead of sub-directories you will need to create a wildcard DNS record on your server to enable the virtual host (sub-domain) functionality of WordPress. Your server must support wildcard DNS records for you to do this. Namecheap hosting supports wildcard DNS.

Follow these instructions to create a wildcard DNS record for a domain.

Wildcard DNS Sub Domain Creation

  • Select “sub-domains” under “Domains” in CPanel.
  • Enter an asterisk “*” in the sub-domain’s name field.
  • Select the TLD the wildcard DNS is to be set up on.
  • Enter the server location address for the wildcard folder, e.g. /public_html/bigbuz/.
  • Click “Create”.

Now you need to configure the newly activated WordPress Network Settings:

  • Navigate to the network settings page in your WordPress dashboard under Tools>Network.
  • Choose whether you want to use sub-domains or sub-directories for the new sites you add to your network.
  • Type a name for your network of sites.
  • Set your admin email address.
  • Click “Install”.

After a minute or two you will see a configuration screen. Back up your .htaccess and wp-config.php files before you proceed to follow the instructions provided on that screen.

Next, create a directory called blogs.dir under your site’s wp-content directory. The address will look like wp-content/blogs.dir/.

Lastly, log out then log back in.

Congratulations on your new WordPress Multi Site installation!

Now you need to go through your settings to enable or disable the new options provided by WordPress MS. Use the Network Admin link at the top left of your admin screen to edit your network’s settings. Browse around, have  a play and you will soon realize how intuitive the Network Admin interface is to navigate.

Maintaining your site’s security is highly important. A quick guide to hardening WordPress against threats is available here.

Extra tip

Prevent visitors to non-existent sites seeing 404 error pages, redirect them to a URL of your choice by adding the below code to the bottom of your wp-config.php file:

/* Send visitors to non-existent blogs here */
define( 'NOBLOGREDIRECT', '' );

Change to the URL you want visitors of deleted, deactivated and non existent sites to be directed to.

Using multiple domains

WordPress MU Domain Mapping lets multisite users map an external domain name onto a child site within your multisite network.

Here’s how to install it:

  • Download the plugin
  • Copy the file sunrise.php from /wp-content/plugins/wordpress-mu-domain-mapping/
  • Place sunrise.php in your site’s /wp-content/ directory
  • Edit your wp-config.phpfile to add this code to the bottom of it:
    define( 'SUNRISE', 'on' );
  • Activate the plugin from your plugin admin panel


This guide was first written in 2010 when WordPress 3.0 launched as the combination of WPMU and regular WordPress. The guide was last updated 11th November 2012.

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Very nice tutorial.  Saw some others but they left out a few steps and it was very frustrating.
Followed yours and had it done in a matter of minutes…dropped in Buddypress and we are on our way.
Looks just like my MU installations (with the 3.0 upgrade of course)
I would suspect that you will start to get a boost in traffic on this post starting today.
Nice job.

Thanks for the compliment. I actually read that post too.
I really haven’t found too many problems updating.
I had some old plug ins that I was concerned about anyway, but I really only had to ditch one, out of the few sites that I have upgraded so far…and I expected to have to do so.

Just did my oldest site (4 years) with a 2 year old theme from Solostream, , and even that went well.

I am pleasantly pleased and surprised.

Can I add existing WordPress sites under a single WordPress installation? Will the plug-ins installed on one, effect the others? For example, I have customized the admin dashboard with Dashboard Editor in one theme, if I enable the Multi Site will ALL of the admin dashboards be customized in like manner? Thanks in advance.

I currently have two WP blogs under one account on Bluehost. I’m not very good with the technical side of blogs, but I think that they both have their own installation with one being a subdomain of the main account. Both sites have their own URL and files on the host site. I want to set up a new network of sites using 3.0 Multi-Site. I want to have one master site that I keep updated and thus updates all of the network sites, and charge a nominal fee to real estate agents at my company to get them set… Read more »

Actually, though Bluehost’s support files do say that they don’t support wildcard DNS, I just setup a WP3.0 MS using subdomains with no issue. I added the asterisk subdomain to in Bluehost’s subdomain manager, set up as the main domain, enabled Multi-Site, and created a new “site” as To make sure it wasn’t the same content, I changed the “Hello World!” post of and created a It works. Maybe it’s a fluke (which I doubt) or a brand new feature, which would be surprising but not impossible. The “redirects” page does talk about wildcards: Checking… Read more »

Not sure if you’ll see this comment, Enkerli, since your post here is 2 years old, but wanted to say that this instruction for how to do multisite with BlueHost was extremely helpful. I’m running a multisite network on the primary domain, and with your help was able to set up a different multisite network on an addon domain. Thank you!

Really glad to know it helped! Makes it worth the “effort”… ;-)

Le 2012-07-31 à 16:26, “Disqus” a écrit :

Thanks for the article it was very helpful. I am interested in using YAMM plugin to manage multiple domains. However there is no proper documentation available on the plugin website.

I have 2 domains say and is running WordPress 3 with multi user enabled (Thanks to you :) ). Now I want to use the same wordpress 3 setup for as well. I have installed and enabled the plugin YAMM. What changes do I need to do in my DNS control panel so that I can create new blogs (subdomain) on using this setup ??

Thanks.. Looking forward to your reply :)

Thanks for this nice explanation. One of my friends was asking me for this info. I can refer her to your page now; I’ll look forward to more interesting articles in the days to come.

I’m wondering if you can use add-on domains as users without involving YAMM. You set up WP to use sub-directories for the child blogs, and you install the child blog in the subdirectory that cPanel assigns for the add-on domain. Would the add-on domain’s URL take the visitor to the child blog?

Thanks, Dion. I may have to wait for WP3 to have this as an included function. I was unable to connect your instructions for YAMM with what my registrar wants in the zone record fields: Host, TTL, Type/Priority, and Value. I’ve only supply DNS values to domains and am unfamiliar with zone records.


I’m about to do this but Im verrrry scared about losing everything on my site. What happens to comments etc when you disable the plugins and then reactivate them?

How do you check if plugins can work sitewide?

How do you backup if it all goes horribly wrong?


Thanks for the quick response, its bp colours from here although I have customised it quite a bit. Im a bit concerned about the details of the site being lost. ie. Member login data, profile fields. Have you done this upgrade before?


Thanks, followed this step by step, worked perfect on my existing wordpress site. Your writing is clear, concise and execellent–and that comes from an author of five photography books! Thanks again, rg.



Really great article, very helpful.

I’ve written a guide that goes into quite a lot of detail about .htaccess configuration and editing the wp-config file.

Have a look:

I want three installs (primary domain name plus two folders). I have about 20 pages. I want 18 of those to be shared between the installs. I want 2 each to be unique to each install. Because I have different users, I want to have each install have exclusive access to the 2 pages. I don’t want other installs have access to those folder-specific pages.

Can this be done?

Hi There. I intend to follow your instructions above for installing WP Multi-user. I am not technical and have very little web experience, but I’m going to give it a go. I am a marketing consultant and used WP to develop my own site. I will now be developing sites for some of my clients. I would like to keep my site separate from the client network. Is there a way to do that? And, also, in my case I am not clear on the difference between sub-domains and sub-directories and which might be better for my application. Basically I… Read more »

This has been quite helpful. I am currently looking into building up my WordPress MU site. Thanks for the tips.

Amazing. thanks for keeping this article here.

i was struggling with wild card issue with Multisite with bluehost. spent lot of time. Conguired Multisite in my mai domain but when i configure subdomain, redirection was not happenning to the main domain folder.

thanks and you saved my lot of time.



Hi Dion – looks like you wrote this in June 2010, so just checking (before I wade in and try any of this) that the info here is all still applicable, and that WP 3 hasn’t changed and rendered any of this obsolete – I know a lot can change in 6+ months :) – I’m guessing more and more people will be looking into multisites.



Hi there, You’ve done a great job. I’ll definitely digg it and personally suggest to my friends. I’m confident they’ll be benefited from this website.

Robert Sanburg

I don’t normally comment on blogs.. But nice post! I just bookmarked your site

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I found your blog from cuil and it is amazing. Thanks for providing such an informative post!

Easy to follow steps, thanks a lot for sharing. This tips are working. 


I’ve been searching around the web for answers to my question and you certainly communicate well.  Here’s my situation. I have a wordpress blog that has been installed since August 2011.  I recently upgraded to the latest 3. version of wordpress (multiuser), then installed buddypress and bbpress on it. Using the latest versions. I did not do the network installation and after reading stuff at the WPMU site, I am afraid that if I follow the procedure at the beginning of this article that I will corrupt my site.  My server will only allow the subdirectory (subfolder) option.   In… Read more »


Hi, I am working on a Genesis Theme and have searched all the editor files and I dont seem to have the 
wp-config.php file. Could anyone help me find it! Somewhere I read I have to create one!?!

The file is not in the Genesis theme. wp-config.php is in the website’s root directory (where you installed the WordPress files).

I need to make a correction to this post. There is an issue with centering the menu and Droid phones. Will figure a fix for it today and update this post as soon as I have it.

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One more thing you may have to do if you are using Hostgator. You’ll need to go into the Advanced DNS Zone Editor in your sites cPanel and delete the webdisk.* as it interferes with the Wildcard DNS setting.

Thanks for the post.

Some hosting doesn’t allow WPMU. t will save some space, because we only need single WP installation. But, that’s make thath ‘single’ index.php over requested. Can you explain it? I’m noobs.

yazı için teşekkürler..

Olá, segui os passos, mas ao criar alguma site no wordpress, eu não consigo acessar o Painel desse site, aparece um erro de página não disponível. Por exemplo, ao criar o site, a criação tem sucesso. Mas então eu clico em Painel para configurar as páginas ele vai para o endereço, então aparece página não disponível.
O que pode ser?

tabi ya cok iyi ama simdi denedim olmadi yapamadim