root@recode:/# mdadm --assemble --scan -v
mdadm: looking for devices for /dev/md0
mdadm: cannot open device /dev/dm-0: Device or resource busy
mdadm: /dev/dm-0 has wrong uuid.
mdadm: no RAID superblock on /dev/sdc
mdadm: /dev/sdc has wrong uuid.
mdadm: no RAID superblock on /dev/sdb
mdadm: /dev/sdb has wrong uuid.
mdadm: cannot open device /dev/sda2: Device or resource busy
mdadm: /dev/sda2 has wrong uuid.
mdadm: cannot open device /dev/sda1: Device or resource busy
mdadm: /dev/sda1 has wrong uuid.
mdadm: cannot open device /dev/sda: Device or resource busy
mdadm: /dev/sda has wrong uuid.
mdadm: /dev/sdc1 is identified as a member of /dev/md0, slot 2.
mdadm: /dev/sdb1 is identified as a member of /dev/md0, slot 1.
mdadm: /dev/sda3 is identified as a member of /dev/md0, slot 0.
mdadm: added /dev/sda3 to /dev/md0 as 0
mdadm: added /dev/sdb1 to /dev/md0 as 1
mdadm: added /dev/sdc1 to /dev/md0 as 2
mdadm: /dev/md0 assembled from 1 drive - not enough to start the array.
root@recode:/# cat /proc/mdstat 
Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10] 
md0 : inactive sdc1[2](S) sdb1[1](S) sda3[0](S)
      940185408 blocks
       
unused devices: <none>