Allowing people to set up blogs for WordPress MU at blog.domain.tld requires installing your WPMU in the site root and setting up wildcard DNS. In setting up my first WPMU, I ran across this tutorial by Matt Mullenweg of WordPress fame, linked from the WordPress MU docs.
Since I’m not the queen of DNS or anything, I checked with my admin folks to make sure I got the Virtual Host entries correct. I found out this is extremely easy to do if you have a cPanel setup.
Here’s How from my SysAdmin:
To add wildcard DNS and vhost settings in one swoop, simply add a new sub domain to the account and name it ‘*’ (the asterisk character). Make sure it’s document root is pointed to the same directory that your WordPress MU is setup in and cPanel will add everything else to all of the configuration files.
Sure enough, worked like a charm, took 30 seconds, and didn’t require anything scary like restarting Apache–there is no time that runs slower in the time-space continuum than waiting for httpd to restart, man.