sudo mdadm -D /dev/md127p1
/dev/md127p1:
        Version : 1.2
  Creation Time : Wed May 25 15:13:56 2011
     Raid Level : raid1
     Array Size : 78119936 (74.50 GiB 79.99 GB)
  Used Dev Size : unknown
   Raid Devices : 2
  Total Devices : 1
    Persistence : Superblock is persistent

    Update Time : Wed May 25 16:03:34 2011
          State : active, degraded
 Active Devices : 1
Working Devices : 1
 Failed Devices : 0
  Spare Devices : 0

           Name : jason-OptiPlex-330:0  (local to host jason-OptiPlex-330)
           UUID : 9d94d76c:62019c5b:c8619fec:5762f98d
         Events : 915

    Number   Major   Minor   RaidDevice State
       0       8        1        0      active sync   /dev/sda1
       1       0        0        1      removed