I am getting ready to install ubuntu Server. I have done it many times but never with Raid in mind. I found a little info out there on doing this but I still have a question.

If I plan to have two 500 GB hard drives for backing up several computers in the a network (Raid). Do I need to have a separate hard drive for my OS and home partitions? Or, can I just partition one of the large drive for those areas?

If it matters... I am setting up a small server for Shared files and important backups for 5 computers.