2.2.3 Requirement for installing Oracle Linux 6 Update 10 with UEFI support

If your system supports UEFI boot mode, and you want to boot in this mode to install Oracle Linux 6 Update 10, the target disk must use the GUID Partition Table (GPT), as some UEFI firmwares do not allow UEFI/MBR boot. (Bug ID 28213206)