Hard Drive Encryption

See dm-crypt/Device encryption

List devices on computer

sudo fdisk -l
# or
lsblk

Benchmarking different encryption algorithms

Since changing an encryption cipher of a block device after setup is difficult, it is important to check dm-crypt performance for the individual parameters in advance:

cryptsetup benchmark

can give guidance on deciding for an algorithm and key-size prior to installation. If certain AES ciphers excel with a considerable higher throughput, these are probably the ones with hardware support in the CPU.

Quoted from here

Encrypting a device with LUKS

See here

# format a LUKS partition, this will prompt you for a password
sudo cryptsetup luksFormat <device>
 
# check the results
sudo cryptsetup luksDump <device>

Accessing a LUKS-encrypted device

See here

# this creates a device at `/dev/mapper/<device_mapped_name>`
sudo cryptsetup open <device> <device_mapped_name>
# example
sudo cryptsetup open /dev/sda1 backup

All access must be through /dev/mapper/backup for the encryption to work. This includes creating a filesystem such as Btrfs.

sudo mkfs.btrfs /dev/mapper/backup

/dev/mapper/backup can be mounted like any regular partition.

To close the LUKS encryption, unmount the partition, then run

sudo cryptsetup close backup