I have a server that runs a proprietary OS (Theos, if you are familiar with it). I want to run at least a RAID 1 configuration with this server. I have received a list of support RAID controllers from the manufacture of the OS. They have told me that the OS doesn't support hotswapping or hot spares; however, since I am configuring a HARDWARE RAID wouldn't this take the OS out of the equation? To me it shouldn't matter what the OS supports (as far as hot swapping and hot spares) if the configuration is a hardware RAID. I would think that if a hardrive failed, and the hardware controller support hot spares, then the rebuild process would happen automatically from controller (as long as you have a spare drive configured in the system). Am I right with this logic?

As long as the rebuild and control is done by hardware it will. At lot of the controlers still use software to control the rebuild when the server is up and running for spare drives. Hot swapping can be a issue. Even OS's that support hot swap config's dont always work properly. I have seen win 2k with hot swap BSOD when you pull a drive from the mirror.