Linux Administration Cookbook

How it works...

What we've done here is simply created an encrypted volume; it's yet another logical disk, that the system can treat as any other storage medium once it's been unlocked.

cryptsetup is the key component used here, and it couldn't be described better than by its own manual page.

cryptsetup is used to conveniently setup dm-crypt managed device-mapper mappings. These include plain dm-crypt volumes and  LUKS  volumes.  The difference is that LUKS uses a metadata header and can hence offer more features than plain dm-crypt. On the other hand, the header is  visible and vulnerable to damage.

With cryptsetup, we started by formatting the partition we'd set up and setting an initial passphrase. This was the luksFormat element. Once ...