It's designed to be flexible and can even store metadata externally so that it can be integrated with other tools. It provides a generic key store (and associated metadata and recovery aids) in a dedicated area on a disk with the ability to use multiple passphrases (or key files) to unlock a stored key. Linux Unified Key Setup ( LUKS) is a disk-encryption system. The answer is to place the data on a drive into a digital vault that can't be opened without information that only you have access to. Computers can be booted from a portable boot drive, which separates a drive from its host operating system and turns it into, virtually, an external drive available for reading. You don't have to physically separate a drive from its computer host for this trick to work, either.

The problem, as many a computer technician understands, is that hard drives can be extracted from computers, and some drives are already external by design (USB thumb drives, for instance), so they can be attached to any computer for full access to the data on them.

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Encrypting external hard drive