Why doesn't Red Hat detect hard drive on HP BL460C Gen 8?

EDIT: The server I am using is HP BL460C Gen 8 having real hardware RAID. I am trying to install Red Hat Enterprise x86_64 bit on an HP ProLiant (iLO 4) server with an Array of 2 hard drives configured as RAID1. The built in server manager allows me to change the setting and configuration of the storage array between RAID0 and RAID1 But RED HAT starts the process of the clean install, and i get to select the time, language, etc. but it stops because it could not detect a storage disk. All it can see is the virtual boot drive that it creates while booting to allow it to run (capacity 256 MB). I tried to manually/custom add the storage setting but again, all available storage is 250 mb and all found devices is 1. What am I doing wrong?