[CentOS] Help. Failed event on md1

Hi all,
This morning I received this notification from mdadm:
This is an automatically generated mail message from mdadm
running on server-mail.mydomain.kom
A Fail event had been detected on md device /dev/md1.
Faithfully yours, etc.

In /proc/mdstat I see this:
Personalities : [raid1]
md1 : active raid1 sdb2[2](F) sda2[0]
      77842880 blocks [2/1] [U_]

md0 : active raid1 sdb1[1] sda1[0]
      305088 blocks [2/2] [UU]

unused devices: <none>


Pls help me. What should I do?
Thank you very much,
-- 
Fajar Priyanto | Reg'd Linux User #327841 | Linux tutorial 
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