== install ==

# install needed packages
apt-get install cryptsetup
# install modules
echo "aes" >> /etc/modules
echo "dm_mod" >> /etc/modules
echo "dm_crypt" >> /etc/modules
modprobe aes
modprobe dm_mod
modprobe dm_crypt
# create container directory
mkdir /crypt

== init container ==

# create container (20GB = 20 * 1024 * 1M)
dd if=/dev/urandom of=/crypt/data.crypt bs=1M count=20480
# create loop back device
losetup /dev/loop0 /crypt/data.crypt
# init crypted device (device name is data.crypt)
cryptsetup -c aes create data.crypt /dev/loop0
# create fs (device name is data.crypt)
mke2fs -j /dev/mapper/data.crypt
# create mount point
mkdir /mnt/encrypted
# remove device (device name is data.crypt)
cryptsetup remove data.crypt
# remove loop back device
losetup -d /dev/loop0

== mount container ==

# create loop back device
losetup /dev/loop0 /crypt/data.crypt
# init crypted device (device name is data.crypt)
cryptsetup create data.crypt /dev/loop0
# mount crypted device (device name is data.crypt)
mount /dev/mapper/data.crypt /mnt/encrypted

== umount container ==

# mount crypted device
umount /mnt/encrypted
# remove cytpted device
cryptsetup remove data.crypt
# remove loop back device
losetup -d /dev/loop0