I’ve installed a RAID controller into my VMware ESXi host, but it’s not detecting my RAID array – it shows all the drives in ESXi. Why is the RAID set not detected by ESXi when it’s set up in the RAID controllers BIOS?
Short answer: The RAID controller is not supported in ESXi. You need to buy a RAID controller that is listed in the VMware Hardware Compatibility list.
Long answer: The RAID controller isn’t quite a hardware RAID controller – it’s actually a hardware controller capable of having RAID setup in the software (OS). ESXi doesn’t have the software installed to set up or understand the RAID. Consequently you are able to set up the RAID in the BIOS of the controller, but when ESXi loads up it does not detect the RAID and you end up with a list of disks.