- Install mdadm easy by apt-get install mdadm - Change a disk to md format: fdisk /dev/sdd press n to create press t to change format, choose fd - Create a new synching disks. Paired: mdadm --create --verbose /dev/md3 --level=1 --raid-devices=2 /dev/sdb1 /dev/sdd1 shutdown –r now - Check all md more