If you want to encrypt and secure your personal confident data on Linux, here is how to do it.
The following method explains how to encrypt a harddisk or partition and mount it as a folder anywhere in your filesystem. There are also other possibilities like using a file as encrypted container or encrypting your whole system partition.
We will be using dm-crypt + LUKS (Linux Unified Key Setup-on-disk-format), which is a block device level encryption scheme just like Truecrypt.
First you need to install some dependencies:
yum install cryptsetup-luks pv