The two BNAS drives which are normally mirrored via our AMT board (JM 393 chipset) can only be used as JBOD (Just a Bunch of Disks) aka “stand alone drives” if the SATA controller they are plugged into supports port multipler. By default this is not the shipped configuration.
Ask your sales rep for to configure your BNAS with a sata controller with Marvell or other port multiplier aware chipset if you want JBOD capability.