Pete Mall@petemall

pete@jointforcestech.com

WordPress MU 101

What is WordPress MU

• Underlying software for wordpress.com• Multi-user version of WordPress• Unlimited users and blogs• Scalable• Independent permissions, themes & plugins• Powerful CMS• WordPress and WordPress MU to be merged

Who is WPMU for?

• Newspapers and Magazines• Universities• Blog Networks• Niche-specific blog hosts• You?

Why use WordPress MU?

• Supports multiple blogs and bloggers• Easily switch between blogs• Single install – easy to update• Easy to manage plugins and themes• Content Management System

WordPress MU Requirements

• PHP version 4.3 or greater• MySQL version 4.0 or greater• Apache mod_rewrite (Linux Hosting

Recommended)• Wildcard CNAME record for subdomain• Avoid Shared Hosting

Configure Apache

• Add the following to httpd.conf/usr/lib/apache2/modules/mod_rewrite.so

• Virtual Host <Directory> directiveReplace “AllowOverride None” with

“AllowOverride FileInfo Options”

Installing WordPress MU

• Create database for WordPress MU• Download and extract• Set permission to / and /wp-content to 777• Run WordPress MU installation script• Wait for the Magic!• Reset the permission to / and /wp-content to

755

Configuration

Sub-domain vs Sub-directory

• Sub-domain: blog.domain.com• Sub-directory: domain.com/blog

Configuration: Sub-domains

• DNS Wildcard Record*.domain.com. 14400 IN A 76.74.254.126

• Add the following to httpd.conf under <VirtualHost>ServerAlias *.domain.com

Plugins

• Regular Plugins: wp-content/plugins• MU Plugins: wp-content/mu-plugins• Site-wide plugins• Blog specific plugins

Installing Regular Plugins

/wp-content/plugins

• Enable plugin access:Site Admin > Options > Menus > Plugins

• Download and extract to wp-content/plugins• Activate plugins sitewide• Activate plugins on a per-blog basis

Installing MU Plugins

/wp-content/mu-plugins

• Not recommended for WordPress plugins• Download and extract to wp-content/mu-plugins• Plugins are automatically activated sitewide• Plugins don’t appear wp-admin > plugins• Blogs owners have no control over plugins• Core site plugins

Installing Themes

• Download and extract to wp-content/themes/• Activate themes before they can be used• Activate themes sitewide:

Site Admin > Themes > “yes under activate”• Blog specific themes:

Site Admin > Blogs > Edit > Blog Themes

Site Options

Site Admin > Options• Allow blog owners to add new users• Allow new registrations * • Banned Names• Restrict new registrations to certain domains • Limit blog upload space• Limit upload file types• Limit upload file size

Caching

• MU caching framework allows third party caching engines

• Two types of caching frameworks:– Object Cache: • Store commonly accessed data in a rapid access

container (RAM / filesystem)

– Full Page Cache: • Store complete web pages • Generally faster, less flexible

Spam

• Spam Comments– Akismet– Hashcash

• Spam Signups– CAPTCHA– .htaccess hack

Code Backup

backup: tar czf backup_html_$(date +%Y_%m_%d-%H_%M).tar.gz html/

exec ./backup

backup_html_2009_10_10-11_43.tar.gz

Database Backup

backupdb: mysqldump -h <hostname> -qp --all-databases | gzip > all-databases_$(date +%Y_%m_%d-%H_%M).sql.gz

exec ./backupdb

all-databases_2009_10_10-11_45.sql.gz

Domain Mapping

• Allow users to map their blog to a domainmyblog.com vs myblog.domain.com

• User points A record to MU site• Domain Mapping plugin maps their domain to

their blog

Multi-DB Plugin

• Standard MU installation requires only one db• Multi-DB plugin splits single db into multiples• Easy to manage• Performance boost

PHP Settings

• Don’t display error messages on productionphp_flag display_errors 0 (.htaccess)register_globals = Off (php.ini)

• Increase memory limit to 32MB or 64MB• Turn GLOBAL variables off

php_flag register_globals 0 (.htaccess)display_errors = Of

• Turn error logging on

Questions?

pete@jointforcestech.com@petemall

developersmind.com