Hello,

There are many factors involving in design. I would recommend you to have a look at following thread.

http://datacentertalk.com/showthread.php?t=572


How many square feet is your datacenter?
You need to have very good cooling system.
Backup power
Design & layout
IT solution providers
Disaster discovery plan
Enterprise monitoring system
Fire protection and safety
Physical security
Open rack or closed rack solution

What are the parts have you completed? Have you checked out Sun’s datacenter design simulator?