What is LUKS disk encryption and how can it be implemented?

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  • Red Hat Enterprise Linux (RHEL) 5, 6, 7, 8


  • What is LUKS? cryptsetup? dm-crypt?
  • What is the difference between cryptsetup plain and cryptsetup LUKS?
  • What packages are required for LUKS in Red Hat Enterprise Linux?
  • How can LUKS HDD-encryption be accomplished in Red Hat Enterprise Linux?
  • What cipher does LUKS use to encrypt a disk?
  • How big are the encryption keys LUKS uses? Can this be changed?
  • Why do devices encrypted with cryptsetup use a different mode than devices encrypted at install-time?


Diagnostic Steps

WARNING: Encrypting a block device, logical device, or partition containing an existing filesystem or data will wipe the device during the encryption process. Make sure you backup your data to an external source before beginning this procedure!

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When will RHEL officially support "in-place" support for LUKS? (ie. without requiring a backup/reformat/restore approach) There is a project called luksipc that appears to successfully perform an "in-place" conversion: https://www.johannes-bauer.com/linux/luksipc/ and https://github.com/johndoe31415/luksipc. Any chance this project could be /tested/included with RHEL in a future release?

This would be a very useful feature.

Yes!!! An "in-;oace" conversion would be fantastic!!!

These two links:

RHEL6 Security Guide: LUKS Disk Encryption

RHEL7 Security Guide: Using LUKS Disk Encryption

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