WordPress MU: Overview

During last june, WordPress’ creators announced the « merge » of WordPress and WordPress MU. We have still no date, but since the version 2.7, evolutions of these two platforms are synchronized.
To anticipate this merge, I am interested in this MU branch, trying to see if it could open up new possibilities in terms of application, plugins, …
Before discussing about application’s potential, we have, in a first step, to discover it, what I propose in this post series. On the menu of the first issue: presentation of WordPress MU.

MU ?

WordPress MU is a version « multi-blogs » of WordPress.

WordPress manages a single blog, with one or several users (authors, administrators, editors, …). Create an additional blog, requires to install a new WordPress engine, with a new database instance (new tables). Users accounts are specific to each blog.

WordPress MU allows to create and manage several blogs from a single engine. Users are managed by the engine, that gives them the privileges / rights (read, modify, …) on each blog.

WordPress MU can be seen as an envelop / wrapper WordPress.

Why ?

In a first step, I see two main usages for this kind of product:

  • Blog hosting: WordPress MU allowing to create blogs on the fly, it facilitates the creation of blog hosting platform. With few clicks, we can add or delete a blog, assigning it an administrator and users,
  • Manage several blogs: managing several blogs can became very quickly a true nightmare. We have to align WordPress versions, plugins, maintain themes, ensure backups, … With only one engine, and therefore one set of plugins, and a single database, WordPress MU greatly simplifies the maintenance task.

Quick tour

The following screenshots show the main differences between the standard version and MU. Tests are performed with the version 2.9.1 RC1 of WordPress MU.

Installation screen - Part 1
Installation screen - Part 1
Installation screen - Part 2
Installation screen - Part 2
Installation screen - Part 3
Installation screen - Part 3

The installation phase is almost automatic. We just have to create a MySQL database, and then fill the fields shown in the previous screens. The script performs the installation without any other interaction.

Login screen
Login screen

In this screen, we can’t say if we work with MU or standard version.

Sometimes, the first login can be impossible. The screen loops, without any error message. I found two solutions:

  • You can’t empty / flush the browser cache, before the first login,
  • and if this solution doesn’t work, you can add the following lines in the file wp-config.php, located in the root of the blog:
define('ADMIN_COOKIE_PATH', '/');
define('COOKIE_DOMAIN', '');
define('COOKIEPATH', '');
define('SITECOOKIEPATH', '');

At this step, the site is working, with a default blog, that contains some default items (category, post, …).

Page publique par défaut
Default public page

The administration interface of the admin account is the following:

Administration interface
Administration interface

Menus are very similar, compared with standard version, except for the first:

MU specific menus
MU specific menus

Options at site level are numerous, and allow to provide default values for blogs we will create after:

Options page - Part 1
Options page - Part 1
Options page - Part 2
Options page - Part 2
Options page - Part 3
Options page - Part 3
Options page - Part 4
Options page - Part 4

To add a new blog, we just have to fill some fields:

Add a blog
Add a blog

Without specific action, new blogs are always attached to the same user (admin). For a better efficiency, it is better to create some users before, and then attached then to the new blog during its creation phase.

If a user has the suitable rights, he can easily switch from a blog to another:

Swith from a blog interface to another blog interface
Swith from a blog interface to another blog interface
The interface of the new blog
The interface of the new blog

WordPress MU is designed to manage blogs belonging to several users: the security is enforced, especially to access to functions such as themes management, or plugins management.

Locked plugins page
Locked plugins page

Plugin page activation
Plugin page activation

Pros / Cons

In fact, WordPress MU is quit similar than WordPress. As mentioned in the introduction, since version 2.7, both engines have the same interface and nearly the same code.

For an author managing only a single blog, WordPress MU is useless. The soft is really useful when we have to manage several blogs.

After several days of use, my analysis is the following:

Benefits

  • Centralized Management (plugins, users, …),
  • Single administration interface for all managed blogs,
  • On the fly creation of blogs without special installation.

Disadvantages

  • Pooling problems: in case of failure, at engine or plugins level, all blogs are affected at the same time,
  • According the previous sentence: plugins updates are more delicate. We must ensure that the update does not disturb any blog of the platform,
  • Platform is slightly more resource-intensive.

Some comments about the installation: The installation requires more preparation and anticipation of what could become the structure of blogs (especially DNS). Prerequisites for the MU version is also slightly more restrictive than for WordPress.

Overall, manage multiple blogs from a single administration interface provides a real comfort. This centralized management may lose some flexibility, if the blogs are owned by different people, but the time benefits is greatly positive.

For me, easing the creation and management of multiple blogs, WordPress MU will open new fields of use. Taking the case of this blog, for example:

  • I classify my posts in 4 categories: Perso, Techno, Photo Developmentg. This structure is absolutely not optimized for SEO. The idea could be creating a blog for each area (each category). With WordPress MU, I can do that very easily, with the ability to use different themes for each category,
  • Multilingualism could be managed using one blog per language.

WordPress MU opens a door much larger than it appears initially: we can, for example, develop plugins using several blogs.

Conclusion

For those who didn’t know WordPress MU before, this version seems to be « mysterious ». It is seen as a more complex to manage, and without true values added for ordinary bloggers.

But when looking more closely, MU and « standard » wordPress versions, are very similar, especially at the level of the administration interface.

The biggest difference lies in the installation that requires better preparation, especially on DNS and Web server. The complexity is more at the level of the configuration of Apache server, than at the level of WordPress.

In an upcoming post, we look at further detail in the engine.