and, of course, mdadm runs in monitoring mode and sends emails like these:

Code:
This is an automatically generated mail message from mdadm
running on haze

A DegradedArray event had been detected on md device /dev/md0.

Faithfully yours, etc.

P.S. The /proc/mdstat file currently contains the following:

Personalities : [raid1] [raid6] [raid5] [raid4] 
md1 : active raid5 sdd1[0] sda1[2] sdc1[1]
      390716672 blocks level 5, 64k chunk, algorithm 2 [3/3] [UUU]
      
md0 : active raid1 sdc2[1]
      3783232 blocks [2/1] [_U]
      
unused devices: <none>
_________________________
LittleBlueThing Running twin 30's