mdadm --query --detail /dev/md1
/dev/md1:
        Version : 00.90
  Creation Time : Sun Apr 26 21:39:32 2009
     Raid Level : raid1
     Array Size : 952758784 (908.62 GiB 975.62 GB)
  Used Dev Size : 952758784 (908.62 GiB 975.62 GB)
   Raid Devices : 2
  Total Devices : 1
Preferred Minor : 1
    Persistence : Superblock is persistent

    Update Time : Sun Apr 26 22:57:43 2009
          State : clean, degraded
 Active Devices : 1
Working Devices : 1
 Failed Devices : 0
  Spare Devices : 0

           UUID : e7785622:c3210965:7ac07f8f:ee0f6028
         Events : 0.366

    Number   Major   Minor   RaidDevice State
       0       0        0        0      removed
       1     252        3        1      active sync   /dev/block/252:3