Encrypted drive setup

In my personal setup, I keep my files in a dedicated ext4 partition encrypted with LUKS.

Creating the device

Create an empty, unformatted partition with fdisk, GParted, etc., and format it with cryptsetup as follows:

# cryptsetup luksFormat /dev/...

Then, unlock the freshly created LUKS partition:

# sudo udisksctl unlock -b /dev/...
Unlocked /dev/... as /dev/dm-2.

Now, create a Linux partition inside it:

# mkfs.ext4 -L igkdata /dev/dm-2

Mount the filesystem, and change the owner:

# mount /dev/dm-2 /mnt
# chown -R g:g /mnt

In order to mount it, first unlock the encrypted device:

# lsblk
# udisksctl unlock -b /dev/...

The output from this command lists the path to the newly created block device file that can be used to mount the partition:

# mkdir /igk
# mount /dev/dm-0 /igk

The following commands allow to mount this partition at boot:

# blkid
# echo igk-disk /dev/... none luks >> /etc/crypttab
# echo /dev/disk/by-label/igkdata /igk ext4 defaults 0 0 >> /etc/fstab

As it is now, this requires manually entering the decryption password every boot.