Device Mapper DM Encryption dm-crypt

The device-mapper crypt target provides transparent encryption of block devices using the kernel crypto API. DM-crypt is a well-known block device encryption layer. Perhaps the best thing about block device-layer encryption is that it is an order of magnitude simpler to implement than file system layer encryption. Another advantage of block device-layer encryption is that it will encrypt the entire file system, including all of the file system metadata

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