mdadm

mdadm is a Linux utility used to manage and monitor software RAID devices. It is used in modern Linux distributions in place of older software RAID utilities such as raidtools2 or raidtools.[2][3][4]

mdadm is free software maintained by, and copyrighted to, Neil Brown of SUSE, and licensed under the terms of version 2 or later of the GNU General Public License.

Create SOFT-RAID with mdadm

RAID50

in order to create such array, we must split task: first create 2 sets of RAID5, and then combine these 2 into a RAID0.

Raid5:

  mdadm --create --verbose /dev/md1 --level=5 --raid-devices=4 /dev/sdc /dev/sdd /dev/sde /dev/sdf
  mdadm --create --verbose /dev/md2 --level=5 --raid-devices=4 /dev/sdg /dev/sdh /dev/sdi /dev/sdj

then RAID0:

  mdadm --create --verbose /dev/md0 --level=0 --raid-devices=2 /dev/md1 /dev/md2