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Question from a Reader: Hosting multiple WordPress blogs on one domain name – Part 1

Mike writes: So I'm a newbie when it comes to wordpress, but I think I can catch on fairly quickly. what I was hoping to find was something that would teach me to have one domain name, and have multiple blogs on that domain name, however, have a main front page, that would have that blog orginized into various preview posts.

So this is a relatively easy job, but it should be noted that there are probably numerous ways to accomplish what Mike is after. His problem really is in two parts, so I'll offer my solution to one, and later, some ideas at how to solve the other...

The good news is, WordPress is made to do this. In fact, I'd wager there's already some documentation on their site on how to do it. Its worth discussing though, just to get ideas flowing.
Probably the first thing you'll want to do is come up with a naming strategy for your sub-sites. Do you want to use www.mysite.com/subsite1 or do you want subsite1.mysite.com? Actually it doesn't matter from an installation perspective, but its certainly a useability concern, and one approach will dictate some additional work with your hosting provider.

Here's a screen shot of the top level web directory of a website. You can see each of my subsites, as well as some supporting folders for the entry level site...

I chose a naming convention that reverses the domain names, simply because the sort order makes it easier for me to find things. Note that in the subdomain approach (subsite1.mysite.com) the folder names don't really matter -- I'm going to hide them from users. If I chose a subfolder approach (mysite.com/subsite1) the folder names would be important (at least in a simple setup).

In Mike's case, the entry site (or root site, or main site) will not contain a WordPress installation. This is because what he wants to do can't be done by WordPress (see part 2.) In my case, the root site doesn't contain a WordPress install either, but through some magic I'll discuss later, the top domain redirects to a WordPress-driven sub-site

Note, for interests sake, that I can also host sites with unrelated domain name is the same manor. For example, my parent's site, www.spwise.com, bounces off my server -- it currently just redirects to another site, but I host the domain name.

Ok, now if all of that is as clear as mud, here's where it gets easy. Download the latest WordPress zip archive, unzip it, and upload it as many times as you want to your server -- one for each subsite you want to have. Just make sure you rename the "Wordpress" folder each time, to avoid over-writing it.

So if I wanted to make the site www.jwcars.com and have the following subsites www.jwcars.com/blue-cars, www.jwcars.com/red-cars, www.jwcars.com/green-cars, I'd upload the WordPress folder 3 times, and rename the folders to blue-cars, red-cars and green-cars. Your web root folder would look something like this...

Each folder is a separate and complete WordPress installation

Now use your browser to go to the WordPress install page in each of those folders, and set-up the sites. At this point, each of the sites should have its own set-of tables in your WordPress database. You can share registration/log-in information between the sites, by doing a little hacking in the WordPress code -- that's outside of the scope of this write-up, but you'll find some tips on sharing config tables between multiple blogs here.

If you want to use the subdomain approach, you'll need a decent web hosting provider that lets you have access to some more advanced stuff. I'd imagine all the good ones let you do this, but I use WestHost and have been very happy with how much they let me configure on my own. Here's how I configure a subdomain on my server. You'll need to do something similar, but the exact steps will vary by service provider...

Here I point the subdomain testblog to the server path /var/www/html/com.server.testblog

You now have n number of websites running on one server. The only problem is, there's nothing running on your entry site. If people go to www.jwcars.com/blue-cars everything looks great. But if they go to www.jwcars.com they'll get a 404 error, or worse.
In part 2, we'll discuss some ideas for how the entry site might work. Its considerably more complicated, and requires a lot more custom coding, so I won't be able to provide the actual solution, but WordPress offers enough functionality to get us off on the right foot...