fdisk -l  | grep raid


/dev/sdb1            2048   102402047    51200000   fd  Linux raid autodetect
/dev/sdb2   *   102402048   102811647      204800   fd  Linux raid autodetect

sudo lsblk

aptitude -y install mdadm raidutils

mdadm --examine /dev/sdb1
mdadm --examine /dev/sdb2

mkdir /mnt/md{0,1}

mdadm --assemble --run /dev/md0 /dev/sdb1
mdadm: /dev/md0 has been started with 1 drive (out of 2).

mdadm --assemble --run /dev/md1 /dev/sdb2
mdadm: /dev/md1 has been started with 1 drive (out of 2).

mount /dev/md0 /mnt/md0
mount /dev/md1 /mnt/md1

aptitude -y install cryptsetup

mkdir /mnt/raid_luks

cryptsetup luksOpen /dev/md1 raid_luks
Enter password:

mount /dev/mapper/raid_luks /mnt/raid_luks

umount /mnt/md0
umount /mnt/md1

mdadm --stop /dev/md0
mdadm --stop /dev/md1

sudo mdadm --assemble --readonly /dev/md123 /dev/sdh2
mdadm: /dev/sdh2 is busy - skipping

sudo mdadm --stop /dev/md123
mdadm: stopped /dev/md123

sudo mdadm --assemble --run /dev/md123 /dev/sdh2
mdadm: /dev/md123 has been started with 1 drive (out of 2).