crypttab and fstab UUID's

This works: crypttab: sda2_crypt UUID=6bbba323-ddad-479d-863e-4bd939b46f96 none luks,swap sda3_crypt UUID=3087cec6-dcc9-44ee-8a08-5555bb2ca566 none luks fstab: /dev/mapper/sda3_crypt / ext4 errors=remount-ro 0 1 /dev/mapper/sda2_crypt none swap sw 0 0 But when I try to change it to this and run update-initramfs -u -k all, it gives me this error: cryptsetup: WARNING: failed to determine cipher modules to load for part_root_crypt crypttab: part_swap_crypt UUID=6bbba323-ddad-479d-863e-4bd939b46f96 none luks,swap part_root_crypt UUID=3087cec6-dcc9-44ee-8a08-5555bb2ca566 none luks fstab: /dev/mapper/part_root_crypt / ext4 errors=remount-ro 0 1 /dev/mapper/part_swap_crypt none swap sw 0 0 I wanted to change this because when I installed my operative system, this disk was sda, but afterwards I've added more disks and now it's sdb and I'd like to change it's name to something disk independent. What am I missing here?