Topic: DegradedArray event has been detected on md device /dev/md2. (SOLVED)

[ber]

SME 7.5 ( all updates installed), gateway/server mode/ 2 80GB Disk in RAID1

Hi I've got the following notification by email after i booted the server during updates installation.
Server runs fine but am wary of the notification and miscellaneous errors related to the RAID.
My main problem is trying to discern clearly-

What is the problem and how do I solve it? 

By the way- there are no discern-able problem with the server which we use as a web/email/file server.

It is backed up every night.

I get the following email after a boot.

<sub>This is an automatically generated mail message from mdadm running on server.ber.local.

A DegradedArray event has been detected on md device /dev/md2.</sub>


here is the screen for the RAID status:

Current RAID status:

Personalities : [raid1]
md2 : active raid1 sdb2[1]
      78043648 blocks [2/1] [_U]
md1 : active raid1 sda1[0] sdb1[1]
      104320 blocks [2/2] [UU]
unused devices: <none>


 ┌────Disk redundancy status as of Saturday February 25, 2012 12:35:18──────┐on
 │ Current RAID status:                                                     │
 │                                                                          │
 │ Personalities : [raid1]                                                  │
 │ md2 : active raid1 sdb2[1]                                               │
 │       78043648 blocks [2/1] [_U]                                         │
 │ md1 : active raid1 sda1[0] sdb1[1]                                       │
 │       104320 blocks [2/2] [UU]                                           │
 │ unused devices: <none>                                                   │
 │                                                                          │
 │                                                                          │
 │ Only some of the RAID devices are unclean.                               │
 │                                                                          │
 │ Manual intervention may be required.                                     │
 │                                                                          │
 │                                                                          │
 │                                                                          │
 │                                                                          │
 │                                                                          │
 ├──────────────────────────────────────────────────────────────────────────┤
 │                                 < Next >                                 │
 └──────────────────────────────────────────────────────────────────────────┘

Here is a current disk status report.

[root@server ~]# fdisk -l | more
Disk /dev/md1 doesn't contain a valid partition table
Disk /dev/md2 doesn't contain a valid partition table
Disk /dev/dm-0 doesn't contain a valid partition table
Disk /dev/dm-1 doesn't contain a valid partition table

Disk /dev/sda: 80.0 GB, 80026361856 bytes
255 heads, 63 sectors/track, 9729 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1          13      104391   fd  Linux raid autodetect
/dev/sda2              14        9729    78043770   fd  Linux raid autodetect

Disk /dev/sdb: 80.0 GB, 80026361856 bytes
255 heads, 63 sectors/track, 9729 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1   *           1          13      104384+  fd  Linux raid autodetect
Partition 1 does not end on cylinder boundary.
/dev/sdb2              13        9729    78043807   fd  Linux raid autodetect

Disk /dev/md1: 106 MB, 106823680 bytes
2 heads, 4 sectors/track, 26080 cylinders
Units = cylinders of 8 * 512 = 4096 bytes


Disk /dev/md2: 79.9 GB, 79916695552 bytes
2 heads, 4 sectors/track, 19510912 cylinders
Units = cylinders of 8 * 512 = 4096 bytes


Disk /dev/dm-0: 78.0 GB, 78014054400 bytes
2 heads, 4 sectors/track, 19046400 cylinders
Units = cylinders of 8 * 512 = 4096 bytes


Disk /dev/dm-1: 1879 MB, 1879048192 bytes
2 heads, 4 sectors/track, 458752 cylinders
Units = cylinders of 8 * 512 = 4096 bytes


Disk /dev/sdc: 250.0 GB, 250058268160 bytes
255 heads, 63 sectors/track, 30401 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/sdc1               1       30401   244196001   83  Linux
[root@server ~]#

Happy to forward more info to give greater clarity on the fault- is any??

[cactus]

If I interpret you information right one of your disks is kicked out of the RAID array, more information here: http://wiki.contribs.org/Raid#Resynchronising_a_Failed_RAID

[ber]

resolved issue by adding the drive back into the system and RAID automatically syncing- thank you cactus for the diagnosis and solution.