Encrypting a USB Flash drive with LUKS

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Here is a quick run through on how to encrypt a USB flash drive using Linux Unified Key Setup (LUKS).

Here is the LUKS config:

[root@localhost jon]# fdisk /dev/sdd
> Command (m for help): n
> Partition type
> p primary (1 primary, 0 extended, 3 free)
> e extended (container for logical partitions)
> Select (default p): p
> Partition number (1-4, default 1): 1
> Using default value 1
> First sector (2048-1015807, default 2048):
> Using default value 2048
> Last sector, +sectors or +size{K,M,G} (2048-1015807, default 1015807):
> Using default value 1015807

> Command (m for help): w<
> The partition table has been altered!
[root@localhost jon]# cryptsetup luksFormat /dev/sdc1
WARNING!
========
> This will overwrite data on /dev/sdd1 irrevocably.
>  Are you sure? (Type uppercase yes): YES
> Enter LUKS passphrase:
> Verify passphrase:

[root@localhost jon]# cryptsetup luksOpen /dev/sdc1 LUKS0001
> Enter passphrase for /dev/sdc1:
[root@localhost jon]# mkfs.ext4 /dev/mapper/LUKS0001 -L ENCRYPTED
> mke2fs 1.42.11 (09-Jul-2014)
> Creating filesystem with 244192 1k blocks and 61200 inodes
> Filesystem UUID: d0e027dc-717a-4b79-be53-c35785bc6956
> Superblock backups stored on blocks:
> 8193, 24577, 40961, 57345, 73729, 204801, 221185
> Allocating group tables: done
> Writing inode tables: done
> Creating journal (4096 blocks): done
> Writing superblocks and filesystem accounting information: done

Now pull the flash drive out and re-plug it in. You should be be prompted for your passphrase.

[root@localhost jon]# cryptsetup luksClose LUKS0001