If it’s a true hardware RAID, it should be totally invisible to the OS - everything is handled in the controller card.
Personally, when I setup RAIDed machines, I usually have one non-RAID disk for the root partition, and only use the RAID disks for data. (This works beautifully on a system with 6 disks - 4 for the RAID stripes, 1 un-RAIDed, 1 hot spare).