Licensing/Cloning

Howdy.

We are putting a high-end box in place to be our main database server. By high-end, I mean a dual-processor, 2gb RAM box with RAID 1. We are a small place (only 60 users), however the database is going to serve as our “business runner” application. As such, we want to maintain a duplicate of the box in storage in case the main box ever fails. In keeping with this philosophy, we were wondering if Microsoft allows to maintain a duplicate box that is kept in storage and only coming online when the other box is shutdown for the purposes of updating the data. Specifically licensing. Is it possible to use only one server license? Also, will Active Directory allow for a duplicate machine and not issue multiple SIDs?

Thanks for any info.

Dennis Jones