sudo mdadm --examine /dev/sd[bcde] >> raid.status 
cat raid.status 
/dev/sdb:
   MBR Magic : aa55
Partition[0] :   4294967295 sectors at            1 (type ee)
/dev/sdc:
          Magic : a92b4efc
        Version : 1.2
    Feature Map : 0x0
     Array UUID : bb43bcaf:acfbd176:41132760:a1f0006c
           Name : OMV:Main
  Creation Time : Thu Jun  9 20:20:07 2016
     Raid Level : raid5
   Raid Devices : 4

 Avail Dev Size : 7813775024 (3725.90 GiB 4000.65 GB)
     Array Size : 11720661504 (11177.69 GiB 12001.96 GB)
  Used Dev Size : 7813774336 (3725.90 GiB 4000.65 GB)
    Data Offset : 262144 sectors
   Super Offset : 8 sectors
          State : active
    Device UUID : c657d56f:dd202543:84c8483f:57d15c04

    Update Time : Tue Nov  7 18:34:04 2017
       Checksum : 4e93e38 - correct
         Events : 80082

         Layout : left-symmetric
     Chunk Size : 512K

   Device Role : Active device 0
   Array State : AAAA ('A' == active, '.' == missing)
/dev/sdd:
          Magic : a92b4efc
        Version : 1.2
    Feature Map : 0x0
     Array UUID : bb43bcaf:acfbd176:41132760:a1f0006c
           Name : OMV:Main
  Creation Time : Thu Jun  9 20:20:07 2016
     Raid Level : raid5
   Raid Devices : 4

 Avail Dev Size : 7813775024 (3725.90 GiB 4000.65 GB)
     Array Size : 11720661504 (11177.69 GiB 12001.96 GB)
  Used Dev Size : 7813774336 (3725.90 GiB 4000.65 GB)
    Data Offset : 262144 sectors
   Super Offset : 8 sectors
          State : active
    Device UUID : f5596406:7ef407ed:46b124b8:278210f9

    Update Time : Tue Nov  7 18:34:04 2017
       Checksum : b2eaad9c - correct
         Events : 80082

         Layout : left-symmetric
     Chunk Size : 512K

   Device Role : Active device 1
   Array State : AAAA ('A' == active, '.' == missing)
/dev/sde:
          Magic : a92b4efc
        Version : 1.2
    Feature Map : 0x0
     Array UUID : bb43bcaf:acfbd176:41132760:a1f0006c
           Name : OMV:Main
  Creation Time : Thu Jun  9 20:20:07 2016
     Raid Level : raid5
   Raid Devices : 4

 Avail Dev Size : 7813775024 (3725.90 GiB 4000.65 GB)
     Array Size : 11720661504 (11177.69 GiB 12001.96 GB)
  Used Dev Size : 7813774336 (3725.90 GiB 4000.65 GB)
    Data Offset : 262144 sectors
   Super Offset : 8 sectors
          State : active
    Device UUID : bae65123:0c971f60:b0c46ad3:ccd70895

    Update Time : Tue Nov  7 18:34:04 2017
       Checksum : fa2e45fe - correct
         Events : 80082

         Layout : left-symmetric
     Chunk Size : 512K

   Device Role : Active device 2
   Array State : AAAA ('A' == active, '.' == missing)


cat /proc/mdstat 
Personalities : [raid6] [raid5] [raid4] 
md127 : inactive sdc[0] sde[2] sdd[1]
      11720662536 blocks super 1.2