The My Book Duo 20TB comes pre-configured in RAID0 so users can take mirroring or JBOD, allowing users to use both drives independently. Auto and system backup; RAID-0 ready out of the box; RAID optimized WD. Western Digital My Book Duo 12TB is the perfect solution for photographers Configured as RAID 1, the two drives are mirrored for maximum security. but if you're to keep your files safe, you need a decent backup solution. Getting Started with a My Book Duo. How to format a WD hard drive to exFAT or FAT32 file system · Answer ID This answer WD Backup; WD Universal.