WordPress MU

Hello,

I am not new to WP, but I am definitely new to WP MU. I have 4 domains and I want them to be controlled with single Backend.

For Example:

example1.com
exmaple2.org
example3.net
example4.biz

What should I do to make them all work together? I want to control all example2-4 from example1.com.

Should I install MU WP on example1 and simple WP's on other example domains or should I install MU WP on all 4 domains? I am so confused. can anyone please guide me on this.

Thanks

You can't use WP MU to control 4 blogs with one backend (as far as I know), but you can use it to have 4 blogs with 4 dashboards running on the same codebase, and easy to upgrade etc.

All you need to do, is to install WP MU on one of the domains, create 3 more blogs, and point your other domains to the addresses of the other blogs.

You need the domain mapping plugin:
http://wordpress.org/extend/plugins/wordpress-mu-domain-mapping/

While you will be using one WPMU install to control all the blogs, you still have to login to the backend of each to manage them.

install WPMU.
install the domain mapping plugin.
Set up your blogs.

holler if you get stuck.

Can I use 1 WP MU Installation to upgrade or Manage other WP Blogs? Like Plug-ins or WP Upgrades?

Important : I need only to update and manage wordpress structure (wordpress version and plugins versions) NOT the content.
that is why I am looking for a single administration interface.

Yes, the upgrade is done from one spot. Because you still only have one codebase to work with.

My advice is to actually install it somewhere, and poke around the backend.

Why not use DNS forwarding and masking? If you're just using the same content, wouldn't it be simpler?