Die USB-Sticks sind sdb und sdc und nicht gemounted:
parted /dev/sdb "rm 1"
parted /dev/sdc "rm 1"
parted /dev/sdb "mklabel msdos"
parted /dev/sdc "mklabel msdos"
parted /dev/sdb "mkpart primary ext4 1M -1"
parted /dev/sdc "mkpart primary ext4 1M -1"
parted /dev/sdb "set 1 raid on"
parted /dev/sdc "set 1 raid on"
(apt-get install mdadm)
mdadm --create /dev/md0 --level=0 --raid-devices=2 /dev/sdb1 /dev/sdc1
mkfs -t ext4 /dev/md0
mdadm --detail /dev/md0
/etc/fstab:
/dev/md0 /data ext4 defaults 0 0