April 12, 2010 
Update – if you;re interested in this you should definitely check out this new multi-domain plugin too – allows you to seamlessly run multiple different domains out of one Multisite install, and it works :)
Have you ever wanted the capability to organize your multi-user WordPress site into ranks with multiple admins to handle each of them? WordPress 3.0 presents this opportunity with the help of the new WP Multi Network plugin. John James Jacoby, one of BuddyPress core developers, created this plugin based on the previous work of David Dean. Here’s a quick overview of what it does:
Turn your multi-site installation of WordPress into many multi-site networks, all surrounding one central user base.
WP Multi Network allows cape wearing super admins to create new network collections of sites, allowing for infinitely extensible site, network, and domain arrangements.
This plugin requires WordPress 3.0 beta and you must have the multi-site functionality enabled. If you need instructions for how to do this, check out our recent post on How to Get an Early Start With WordPress Multisite 3.0 Beta. Then if you’re interested in taking it one step further to create a multi-network of sites, each with their own super admins, install the WP Multi Network plugin. Activate it and then you will notice “Networks” as a new menu item under Super Admin. Here you will find a menu that will allow you to create new networks as well as assign sites to each network. You can easily add or remove sites from the network through the network options.
The plugin automatically enables a “network zero” option which, when set to ‘true’, saves orphaned blogs. This means that in case a network is deleted, the orphaned blog will be sent to a holding netowrk. Otherwise you can set the plugin to allow blogs belonging to deleted networks to be deleted.
Possible Applications of WordPress Multi Network
This plugin is exciting because it positions WordPress as a CMS capable of much more than just creating a single network of blogs. WP Multi Network essentially gives the multi-site super admin the ability to manage an entire network of sites with a central place of command, allowing quick upgrades and updates to all of the networks when necessary.
Wow! would this be the answer for including an e-commerce subdomain wp installation which could be accessed by the same users of our primary domain? That would be great!
Wounderfull !!
Them Is Posible this a super-buddypress Network, with more soical bp networks in site, or with oder sites?
Juan – I think this would work for putting e-commerce on a subdomain.
Javier – The thing with BP is that you cannot have multiple separate installations of BP. From my understanding, you can have it running on the other blogs but it has to be set up with the main super admin and is not really a separate social network.
Thank you..really informative!!
Sarah .
Thankyou so much for this information , is it possible that i use the WP 3.0 like WPMU?
I think WP 3.0 is an Integration of WP and WPMU.
Is it true?
Sepehr- It’s true. WP and WPMU are merged in 3.0. Here are some instructions for getting the multisite functionality set up: http://wpmu.org/how-to-get-an-early-start-with-wordpress-multisite-3-0-beta-now-available-for-download/
Sarah! Thanks for writing this article. I am doing research on WP 3.0 and upgrading a test network to the latest RC2. We utilize David Dean’s Mu Multi-Site plugin to manage a large number of domains. Does David’s previous Multi-Site database structure port over to John James Jacoby, WP Multi Network plugin flawlessly?
Time to tinker and prepare for the epic 3.0 release! Party!!!
I read on the WPMU member forum (link requires membership) that this plugin requires significant modifications to other plugins. A huge degree of complexity comes into play when networks on networks are rolled out. The mind boggles.
Can I create a new network using this plugin by parking the particular domain?
I am not sure it is a way to do it .
Thanks !
I am trying to implement this.But unable to find what to enter at “networks” page after installing plugin.Could you help me please .
I am using the plugin and need some help with running it with a ssl cert
I have 2 domains network1 and network2
I have a ssl cert on network1 and neeed all new blogs that get created in network1 to automatically get prefixed with https instead of the default https without that affecting netowrk2
I figured out how to do it with the login and admin area but cannot find the answer to do it on the pages of all new blogs just for the one network..
If you know how to do this.. I appreciate any help..
thanks Scott