cryptsetup luksFormat <device>
cryptsetup open <device> <mapper name>
cryptsetup status <mapper name>
cryptsetup close <mapper name>
See also this good guide on LUKS encryption.
- Ensure it is unmounted
cryptsetup luksFormat /dev/sdb1cryptsetup open /dev/sdb1 cryptusb1mkfs.ext4 /dev/mapper/cryptusb1cryptsetup close cryptusb1- Mount it via file manager