RaidHowTo

truecrypt --text --filesystem=none /dev/sdb1
mdadm --create /dev/md0 --level=5 --raid-devices=3 /dev/mapper/truecrypt1 /dev/mapper/truecrypt2 missing
mdadm --detail /dev/md0
mkfs -t ext3 /dev/md0
mount /dev/md0 /mnt/usbraid
cat /proc/mdstat
mdadm /dev/md0 --add /dev/mapper/truecrypt3