I watched a youtube video where a guy made a raid 1 with 2x 2 gb usb drives. I am using 2 x 3tb disks to have a raid 1 mirror. My concern is my sdb1 size=-1364702208K sdd1 size=-1364702208K. which is half the size of the drives. When the guy done this on his little 2 gb disks, his 2 sizes where still around the 2gb (1.9gb to be exact) mark as was his mdadm size at the bottom.
Also my drives are ext4 not ext2
chris@MediaServer:~$ sudo mdadm --create --verbose /dev/md0 --level=raid1 --raid-devices=2 /dev/sdb1 /dev/sdd1
mdadm: /dev/sdb1 appears to contain an ext2fs file system size=-1364702208K mtime=Thu Jan 1 01:00:00 1970
mdadm: Note: this array has metadata at the start and may not be suitable as a boot device. If you plan to store '/boot' on this device please ensure that your boot-loader understands md/v1.x metadata, or use --metadata=0.90
mdadm: /dev/sdd1 appears to contain an ext2fs file system size=-1364702208K mtime=Thu Jan 1 01:00:00 1970
mdadm: size set to 2930133824K