nas ~ # mdadm -D /dev/md0
/dev/md0:
        Version : 1.0
  Creation Time : Fri Aug 24 04:18:31 2012
     Raid Level : raid1
     Array Size : 511988 (500.07 MiB 524.28 MB)
  Used Dev Size : 511988 (500.07 MiB 524.28 MB)
   Raid Devices : 2
  Total Devices : 3
    Persistence : Superblock is persistent

    Update Time : Wed Dec 11 19:56:04 2013
          State : clean
 Active Devices : 2
Working Devices : 3
 Failed Devices : 0
  Spare Devices : 1

           Name : localhost.localdomain:0
           UUID : 262c8e68:c7c4fa6d:19af27e8:0cfc68a1
         Events : 202

    Number   Major   Minor   RaidDevice State
       0       8        2        0      active sync   /dev/sda2
       4       8       65        1      active sync   /dev/sde1

       3       8       81        -      spare   /dev/sdf1
nas ~ # mdadm -D /dev/md2
/dev/md2:
        Version : 1.2
  Creation Time : Tue Aug 28 04:45:52 2012
     Raid Level : raid5
     Array Size : 78646272 (75.00 GiB 80.53 GB)
  Used Dev Size : 26215424 (25.00 GiB 26.84 GB)
   Raid Devices : 4
  Total Devices : 4
    Persistence : Superblock is persistent

    Update Time : Wed Dec 11 20:04:01 2013
          State : clean
 Active Devices : 4
Working Devices : 4
 Failed Devices : 0
  Spare Devices : 0

         Layout : left-symmetric
     Chunk Size : 512K

           Name : localhost.localdomain:2
           UUID : a9d908f3:f8632fcf:59a69085:83d5f6aa
         Events : 10193

    Number   Major   Minor   RaidDevice State
       0       8        3        0      active sync   /dev/sda3
       6       8       83        1      active sync   /dev/sdf3
       5       8       67        2      active sync   /dev/sde3
       4       8       18        3      active sync   /dev/sdb2
nas ~ # mdadm -D /dev/md4
/dev/md4:
        Version : 1.2
  Creation Time : Mon Dec  9 22:06:12 2013
     Raid Level : raid5
     Array Size : 5753362432 (5486.83 GiB 5891.44 GB)
  Used Dev Size : 2876681216 (2743.42 GiB 2945.72 GB)
   Raid Devices : 3
  Total Devices : 3
    Persistence : Superblock is persistent

  Intent Bitmap : Internal

    Update Time : Wed Dec 11 09:35:53 2013
          State : active
 Active Devices : 3
Working Devices : 3
 Failed Devices : 0
  Spare Devices : 0

         Layout : left-symmetric
     Chunk Size : 512K

           Name : nas:4  (local to host nas)
           UUID : f6924d42:7358df85:416f97f9:83aeac62
         Events : 15769

    Number   Major   Minor   RaidDevice State
       3       8        4        0      active sync   /dev/sda4
       1       8       68        1      active sync   /dev/sde4
       2       8       84        2      active sync   /dev/sdf4