mdadm --examine /dev/sd[abcd]3
/dev/sda3:
          Magic : a92b4efc
        Version : 1.2
    Feature Map : 0x0
     Array UUID : b1009ded:cd1c154e:a47066f1:401f45dd
           Name : NAS542:2  (local to host NAS542)
  Creation Time : Tue Mar 14 15:04:05 2023
     Raid Level : raid5
   Raid Devices : 4

 Avail Dev Size : 3898767360 (1859.08 GiB 1996.17 GB)
     Array Size : 5848150464 (5577.23 GiB 5988.51 GB)
  Used Dev Size : 3898766976 (1859.08 GiB 1996.17 GB)
    Data Offset : 262144 sectors
   Super Offset : 8 sectors
          State : clean
    Device UUID : 3ee637ac:f9bd7b55:62bbd5d1:1ce143d0

    Update Time : Tue Mar 14 16:05:44 2023
       Checksum : 578faca9 - correct
         Events : 146

         Layout : left-symmetric
     Chunk Size : 64K

   Device Role : Active device 0
   Array State : AAAA ('A' == active, '.' == missing)
/dev/sdb3:
          Magic : a92b4efc
        Version : 1.2
    Feature Map : 0x0
     Array UUID : b1009ded:cd1c154e:a47066f1:401f45dd
           Name : NAS542:2  (local to host NAS542)
  Creation Time : Tue Mar 14 15:04:05 2023
     Raid Level : raid5
   Raid Devices : 4

 Avail Dev Size : 3898767360 (1859.08 GiB 1996.17 GB)
     Array Size : 5848151040 (5577.23 GiB 5988.51 GB)
    Data Offset : 262144 sectors
   Super Offset : 8 sectors
          State : clean
    Device UUID : 97c9e64f:9de1443b:47673189:cd2f3fb5

    Update Time : Tue Mar 14 16:13:47 2023
       Checksum : 7d60b1aa - correct
         Events : 158

         Layout : left-symmetric
     Chunk Size : 64K

   Device Role : spare
   Array State : ..AA ('A' == active, '.' == missing)
/dev/sdc3:
          Magic : a92b4efc
        Version : 1.2
    Feature Map : 0x0
     Array UUID : b1009ded:cd1c154e:a47066f1:401f45dd
           Name : NAS542:2  (local to host NAS542)
  Creation Time : Tue Mar 14 15:04:05 2023
     Raid Level : raid5
   Raid Devices : 4

 Avail Dev Size : 3898767360 (1859.08 GiB 1996.17 GB)
     Array Size : 5848151040 (5577.23 GiB 5988.51 GB)
    Data Offset : 262144 sectors
   Super Offset : 8 sectors
          State : clean
    Device UUID : 796d50b5:0a226a8b:cce6d797:449fd317

    Update Time : Tue Mar 14 16:13:47 2023
       Checksum : a42a84f3 - correct
         Events : 158

         Layout : left-symmetric
     Chunk Size : 64K

   Device Role : Active device 2
   Array State : ..AA ('A' == active, '.' == missing)
/dev/sdd3:
          Magic : a92b4efc
        Version : 1.2
    Feature Map : 0x0
     Array UUID : b1009ded:cd1c154e:a47066f1:401f45dd
           Name : NAS542:2  (local to host NAS542)
  Creation Time : Tue Mar 14 15:04:05 2023
     Raid Level : raid5
   Raid Devices : 4

 Avail Dev Size : 3898767360 (1859.08 GiB 1996.17 GB)
     Array Size : 5848151040 (5577.23 GiB 5988.51 GB)
    Data Offset : 262144 sectors
   Super Offset : 8 sectors
          State : clean
    Device UUID : c9565907:5578146d:9d6dfac8:5fc606de

    Update Time : Tue Mar 14 16:13:47 2023
       Checksum : cf33727b - correct
         Events : 158

         Layout : left-symmetric
     Chunk Size : 64K

   Device Role : Active device 3
   Array State : ..AA ('A' == active, '.' == missing)