Topic: DegradedArray event had been detected on md device /dev/md

[imatt]

I have received this message from the raid monitor.
DegradedArray event had been detected on md device /dev/md

I recently suffered a hardware failure on another box (Dying CPU, time sync errors) javascript:emoticon(':cry:') so I rebuilt another box with a fresh SME 7 ISO. I had one HDD on one IDE channel and the CD Drive on the other to install from. I have now disconnected the CD Drive and put an identical 2nd HDD (40GB Seagate) on this second IDE channel and can not seem to get it to recreate the RAID.

I have followed threads in these forums and the output is as follows...

[root@mattsme /]# cat /proc/mdstat
Personalities : [raid1]
md2 : active raid1 hda2[0]
      38973568 blocks [2/1] [U_]
     
md1 : active raid1 hdd1[1] hda1[0]
      104320 blocks [2/2] [UU]
     
unused devices: <none>

and

[root@mattsme /]# mdadm --query --detail /dev/md[12]
/dev/md1:
        Version : 00.90.01
  Creation Time : Mon Sep 18 22:29:10 2006
     Raid Level : raid1
     Array Size : 104320 (101.88 MiB 106.82 MB)
    Device Size : 104320 (101.88 MiB 106.82 MB)
   Raid Devices : 2
  Total Devices : 2
Preferred Minor : 1
    Persistence : Superblock is persistent

    Update Time : Tue Sep 26 20:55:15 2006
          State : clean
 Active Devices : 2
Working Devices : 2
 Failed Devices : 0
  Spare Devices : 0


    Number   Major   Minor   RaidDevice State
       0       3        1        0      active sync   /dev/hda1
       1      22       65        1      active sync   /dev/hdd1
           UUID : ca0df8bf:42376442:5bb64b38:e02b049a
         Events : 0.374
/dev/md2:
        Version : 00.90.01
  Creation Time : Mon Sep 18 22:28:47 2006
     Raid Level : raid1
     Array Size : 38973568 (37.17 GiB 39.91 GB)
    Device Size : 38973568 (37.17 GiB 39.91 GB)
   Raid Devices : 2
  Total Devices : 1
Preferred Minor : 2
    Persistence : Superblock is persistent

    Update Time : Tue Sep 26 21:40:29 2006
          State : clean, degraded
 Active Devices : 1
Working Devices : 1
 Failed Devices : 0
  Spare Devices : 0


    Number   Major   Minor   RaidDevice State
       0       3        2        0      active sync   /dev/hda2
       1       0        0       -1      removed
           UUID : ca3c3164:f8b684d9:565b4de0:8b9146ec
         Events : 0.230986

__________________________________________________
the log file says
2006-09-18 22:39:47.406250500 This appears to be a single disk system - disabling raid monitoring
2006-09-18 23:17:43.391034500 This appears to be a single disk system - disabling raid monitoring
2006-09-19 20:46:20.861324500 This appears to be a single disk system - disabling raid monitoring
2006-09-26 20:53:37.912606500 mdadm: only specify super-minor once, super-minor=2 ignored.
2006-09-26 20:53:37.942195500 mdadm: only specify super-minor once, super-minor=1 ignored.
2006-09-26 20:53:38.777093500 Event: SparesMissing, Device: /dev/md1, Member:
2006-09-26 20:53:39.526293500 Event: DegradedArray, Device: /dev/md2, Member:
2006-09-26 20:53:41.086281500 Event: SparesMissing, Device: /dev/md2, Member:

__________________________

the messages log file says

Sep 26 20:53:37 mattsme kernel: md: raid1 personality registered as nr 3
Sep 26 20:53:37 mattsme kernel: md: Autodetecting RAID arrays.
Sep 26 20:53:37 mattsme kernel: md: invalid raid superblock magic on hdd2
Sep 26 20:53:37 mattsme raidmonitor: Starting raidmonitor:
Sep 26 20:53:37 mattsme kernel: md: hdd2 has invalid sb, not importing!
Sep 26 20:53:37 mattsme kernel: md: autorun ...
Sep 26 20:53:37 mattsme raidmonitor: Starting raidmonitor succeeded
Sep 26 20:53:37 mattsme kernel: md: considering hdd1 ...
Sep 26 20:53:37 mattsme raidmonitor: 
Sep 26 20:53:37 mattsme kernel: md:  adding hdd1 ...
Sep 26 20:53:37 mattsme raidmonitor:
Sep 26 20:53:37 mattsme kernel: md: hda2 has different UUID to hdd1
Sep 26 20:53:37 mattsme rc.e-smith: Starting raidmonitor:  succeeded
Sep 26 20:53:37 mattsme kernel: md:  adding hda1 ...
Sep 26 20:53:38 mattsme kernel: md: created md1
Sep 26 20:53:38 mattsme kernel: md: bind<hda1>
Sep 26 20:53:38 mattsme kernel: md: bind<hdd1>
Sep 26 20:53:38 mattsme kernel: md: running: <hdd1><hda1>
Sep 26 20:53:38 mattsme kernel: raid1: raid set md1 active with 2 out of 2 mirrors
Sep 26 20:53:38 mattsme kernel: md: considering hda2 ...
Sep 26 20:53:38 mattsme kernel: md:  adding hda2 ...
Sep 26 20:53:38 mattsme kernel: md: created md2
Sep 26 20:53:38 mattsme kernel: md: bind<hda2>
Sep 26 20:53:38 mattsme kernel: md: running: <hda2>
Sep 26 20:53:38 mattsme kernel: raid1: raid set md2 active with 1 out of 2 mirrors
Sep 26 20:53:38 mattsme kernel: md: ... autorun DONE.
Sep 26 20:53:38 mattsme kernel: md: Autodetecting RAID arrays.
Sep 26 20:53:38 mattsme kernel: md: autorun ...
Sep 26 20:53:38 mattsme kernel: md: ... autorun DONE.
___________________________________

is this a jumper setting. do they both need to be on master. I think one is master, one is slave.
I have rebooted and the above message is what I receive.

How do I get it to recreate the raid?

admin console says...

  x Manual intervention may be required.

Help, please.

[imatt]

http://bugs.contribs.org/show_bug.cgi?id=959

[imatt]

to get the second disk added i ran

[code]
mdadm -a /dev/md2 /dev/hdc2

[/list]
then ran

[code]
add_mirror -f md2 md1

output was

sfdisk: ERROR: sector 0 does not have an msdos signature

Disk /dev/md1: 26080 cylinders, 2 heads, 4 sectors/track

sfdisk: ERROR: sector 0 does not have an msdos signature
 /dev/md1: unrecognized partition
Old situation:
No partitions found

sfdisk: unrecognized input: unrecognized partition
md1 : active raid1 hdc1[1] hda1[0]
mdadm: hot add failed for /dev/md11: Invalid argument
md2 : active raid1 hdc2[2] hda2[0]
mdadm: hot add failed for /dev/md12: Invalid argument
Forcing grub to rescan devices
Probing devices to guess BIOS drives. This may take a long time.
/dev/md1 does not have any corresponding BIOS drive.
Calling grub-install on /dev/hda
Probing devices to guess BIOS drives. This may take a long time.


    GNU GRUB  version 0.95  (640K lower / 3072K upper memory)

 [ Minimal BASH-like line editing is supported.  For the first word, TAB
   lists possible command completions.  Anywhere else TAB lists the possible
   completions of a device/filename.]
grub> device (hd0) /dev/hda
grub> root (hd0,0)
 Filesystem type is ext2fs, partition type 0xfd
grub> setup (hd0)
 Checking if "/boot/grub/stage1" exists... no
 Checking if "/grub/stage1" exists... yes
 Checking if "/grub/e2fs_stage1_5" exists... yes
 Running "embed /grub/e2fs_stage1_5 (hd0)"...  16 sectors are embedded.
succeeded
 Running "install /grub/stage1 (hd0) (hd0)1+16 p (hd0,0)/grub/stage2 /grub/grub.conf"... succeeded
Done.
grub> Calling grub-install on /dev/hdc
Probing devices to guess BIOS drives. This may take a long time.


    GNU GRUB  version 0.95  (640K lower / 3072K upper memory)

 [ Minimal BASH-like line editing is supported.  For the first word, TAB
   lists possible command completions.  Anywhere else TAB lists the possible
   completions of a device/filename.]
grub> device (hd0) /dev/hdc
grub> root (hd0,0)
 Filesystem type is ext2fs, partition type 0xfd
grub> setup (hd0)
 Checking if "/boot/grub/stage1" exists... no
 Checking if "/grub/stage1" exists... yes
 Checking if "/grub/stage2" exists... yes
 Checking if "/grub/e2fs_stage1_5" exists... yes
 Running "embed /grub/e2fs_stage1_5 (hd0)"...  16 sectors are embedded.
succeeded
 Running "install /grub/stage1 (hd0) (hd0)1+16 p (hd0,0)/grub/stage2 /grub/grub.conf"... succeeded
Done.
grub> quit

then ran

cat /proc/mdstat
Personalities : [raid1]
md2 : active raid1 hdc2[2] hda2[0]
      38973568 blocks [2/1] [U_]
      [>....................]  recovery =  3.8% (1513088/38973568) finish=34.9min speed=17841K/sec
md1 : active raid1 hdc1[1] hda1[0]
      104320 blocks [2/2] [UU]
     
unused devices: <none>

and saw it was recovering

 

Seems like the syntax was wrong. instead of

add_mirror -f hda hdc

which returns

hdc is already in use


it is in fact as above

add_mirror -f md2 md1

I Hopoe this helps someone...

[NickCritten]

Hi iMatt,

Nice work, The  

Code: [Select]

mdadm -a /dev/md2 /dev/hdc2 command sorted me out completely!

However you didn't need the second Command

Code: [Select]

add_mirror -f md2 md1 well I didn't anyway... And as I understand it, I don't see how this could ever work as it would try to add MD2 as a Mirror of MD1 !

Many thanks however, My Raid array 200Miles away is now happily rebuilding