* Raid 6 failing to assemble after machine power loss now, with 1 disk only failed, seems to think its a raid0 array
@ 2016-03-30 21:19 Peter Knight
2016-03-30 22:17 ` Phil Turmel
0 siblings, 1 reply; 4+ messages in thread
From: Peter Knight @ 2016-03-30 21:19 UTC (permalink / raw)
To: linux-raid
Hi,
I hope someone can explain what is going on and hopefully help me
recover my data.
Machine stopped due to power cut it contains 5 hdd with 2 partitions
on each. one set of partitions was a raid1 and this came back fine
showing that disk sdd1 was out of date. the other set of partitions
for raid6 was much less happy. when looking at it (/dev/md126) it
seems to indicate it wants raid level0 but it was a raid6 array (which
has 2 spares) and only lost 1 disk. In case of problems caused by the
out dated partition we zeroed the superblock on the outdated partition
but it still seems to not reassemble the raid6 and says not enough
disks (which there are).
We have tried a manual entry in the /etc/mdadm/mdadm.conf file
specifying this uuid for the device and forcing the raid level to 6
but still no success
What is causing this? and how can I get it reassembled so I can read the data?
Thanks
Peter
Relevant commands and outputs below:
root@Wheal-Peevor:~# cat /proc/mdstat
Personalities : [raid1] [linear] [multipath] [raid0] [raid6] [raid5]
[raid4] [raid10]
md126 : inactive sdc2[1](S) sde2[3](S) sdf2[4](S) sdb2[0](S)
7730171648 blocks
md127 : active raid1 sdc1[1] sde1[3] sdf1[4] sdb1[0]
20971456 blocks [5/4] [UU_UU]
root@Wheal-Peevor:~# mdadm --detail /dev/md127
/dev/md127:
Version : 0.90
Creation Time : Sun Jan 9 14:02:22 2011
Raid Level : raid1
Array Size : 20971456 (20.00 GiB 21.47 GB)
Used Dev Size : 20971456 (20.00 GiB 21.47 GB)
Raid Devices : 5
Total Devices : 4
Preferred Minor : 127
Persistence : Superblock is persistent
Update Time : Wed Mar 30 21:51:26 2016
State : clean, degraded
Active Devices : 4
Working Devices : 4
Failed Devices : 0
Spare Devices : 0
UUID : 504284fe:c53effb7:e9ca3044:bb7815cf (local to host
Wheal-Peevor)
Events : 0.66830
Number Major Minor RaidDevice State
0 8 17 0 active sync /dev/sdb1
1 8 33 1 active sync /dev/sdc1
4 0 0 4 removed
3 8 65 3 active sync /dev/sde1
4 8 81 4 active sync /dev/sdf1
root@Wheal-Peevor:~# mdadm --detail /dev/md126
/dev/md126:
Version : 0.90
Raid Level : raid0
Total Devices : 4
Preferred Minor : 0
Persistence : Superblock is persistent
State : inactive
UUID : 81186e3e:7abdbb10:e9ca3044:bb7815cf (local to host
Wheal-Peevor)
Events : 0.2615946
Number Major Minor RaidDevice
- 8 18 - /dev/sdb2
- 8 34 - /dev/sdc2
- 8 66 - /dev/sde2
- 8 82 - /dev/sdf2
root@Wheal-Peevor:~# mdadm --examine /dev/sd[bcef]2
/dev/sdb2:
Magic : a92b4efc
Version : 0.90.00
UUID : 81186e3e:7abdbb10:e9ca3044:bb7815cf (local to host
Wheal-Peevor)
Creation Time : Sun Jan 9 14:02:38 2011
Raid Level : raid6
Used Dev Size : 1932542912 (1843.02 GiB 1978.92 GB)
Array Size : 5797628736 (5529.05 GiB 5936.77 GB)
Raid Devices : 5
Total Devices : 5
Preferred Minor : 126
Update Time : Sun Mar 13 10:54:22 2016
State : active
Active Devices : 4
Working Devices : 4
Failed Devices : 1
Spare Devices : 0
Checksum : 61abf5fc - correct
Events : 2615946
Layout : left-symmetric
Chunk Size : 64K
Number Major Minor RaidDevice State
this 0 8 18 0 active sync /dev/sdb2
0 0 8 18 0 active sync /dev/sdb2
1 1 8 34 1 active sync /dev/sdc2
2 2 0 0 2 faulty removed
3 3 8 66 3 active sync /dev/sde2
4 4 8 82 4 active sync /dev/sdf2
/dev/sdc2:
Magic : a92b4efc
Version : 0.90.00
UUID : 81186e3e:7abdbb10:e9ca3044:bb7815cf (local to host
Wheal-Peevor)
Creation Time : Sun Jan 9 14:02:38 2011
Raid Level : raid6
Used Dev Size : 1932542912 (1843.02 GiB 1978.92 GB)
Array Size : 5797628736 (5529.05 GiB 5936.77 GB)
Raid Devices : 5
Total Devices : 5
Preferred Minor : 126
Update Time : Sun Mar 13 10:54:22 2016
State : active
Active Devices : 4
Working Devices : 4
Failed Devices : 1
Spare Devices : 0
Checksum : 61abf60e - correct
Events : 2615946
Layout : left-symmetric
Chunk Size : 64K
Number Major Minor RaidDevice State
this 1 8 34 1 active sync /dev/sdc2
0 0 8 18 0 active sync /dev/sdb2
1 1 8 34 1 active sync /dev/sdc2
2 2 0 0 2 faulty removed
3 3 8 66 3 active sync /dev/sde2
4 4 8 82 4 active sync /dev/sdf2
/dev/sde2:
Magic : a92b4efc
Version : 0.90.00
UUID : 81186e3e:7abdbb10:e9ca3044:bb7815cf (local to host
Wheal-Peevor)
Creation Time : Sun Jan 9 14:02:38 2011
Raid Level : raid6
Used Dev Size : 1932542912 (1843.02 GiB 1978.92 GB)
Array Size : 5797628736 (5529.05 GiB 5936.77 GB)
Raid Devices : 5
Total Devices : 5
Preferred Minor : 126
Update Time : Sun Mar 13 10:54:22 2016
State : active
Active Devices : 4
Working Devices : 4
Failed Devices : 1
Spare Devices : 0
Checksum : 61abf632 - correct
Events : 2615946
Layout : left-symmetric
Chunk Size : 64K
Number Major Minor RaidDevice State
this 3 8 66 3 active sync /dev/sde2
0 0 8 18 0 active sync /dev/sdb2
1 1 8 34 1 active sync /dev/sdc2
2 2 0 0 2 faulty removed
3 3 8 66 3 active sync /dev/sde2
4 4 8 82 4 active sync /dev/sdf2
/dev/sdf2:
Magic : a92b4efc
Version : 0.90.00
UUID : 81186e3e:7abdbb10:e9ca3044:bb7815cf (local to host
Wheal-Peevor)
Creation Time : Sun Jan 9 14:02:38 2011
Raid Level : raid6
Used Dev Size : 1932542912 (1843.02 GiB 1978.92 GB)
Array Size : 5797628736 (5529.05 GiB 5936.77 GB)
Raid Devices : 5
Total Devices : 5
Preferred Minor : 126
Update Time : Sun Mar 13 10:54:22 2016
State : active
Active Devices : 4
Working Devices : 4
Failed Devices : 1
Spare Devices : 0
Checksum : 61abf644 - correct
Events : 2615946
Layout : left-symmetric
Chunk Size : 64K
Number Major Minor RaidDevice State
this 4 8 82 4 active sync /dev/sdf2
0 0 8 18 0 active sync /dev/sdb2
1 1 8 34 1 active sync /dev/sdc2
2 2 0 0 2 faulty removed
3 3 8 66 3 active sync /dev/sde2
4 4 8 82 4 active sync /dev/sdf2
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: Raid 6 failing to assemble after machine power loss now, with 1 disk only failed, seems to think its a raid0 array
2016-03-30 21:19 Raid 6 failing to assemble after machine power loss now, with 1 disk only failed, seems to think its a raid0 array Peter Knight
@ 2016-03-30 22:17 ` Phil Turmel
2016-03-31 6:09 ` Peter Knight
0 siblings, 1 reply; 4+ messages in thread
From: Phil Turmel @ 2016-03-30 22:17 UTC (permalink / raw)
To: Peter Knight, linux-raid
On 03/30/2016 05:19 PM, Peter Knight wrote:
> Hi,
>
> I hope someone can explain what is going on and hopefully help me
> recover my data.
> What is causing this? and how can I get it reassembled so I can read the data?
When mdadm assembles an array during boot that has fewer devices than
when it was last shut down (cleanly), it generally declines to start it.
Probably, all you need is:
mdadm --run /dev/md126
{ --detail may not be accurate on an inactive device. The member
--examine data is trustworthy. }
Phil
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: Raid 6 failing to assemble after machine power loss now, with 1 disk only failed, seems to think its a raid0 array
2016-03-30 22:17 ` Phil Turmel
@ 2016-03-31 6:09 ` Peter Knight
2016-03-31 7:01 ` Adam Goryachev
0 siblings, 1 reply; 4+ messages in thread
From: Peter Knight @ 2016-03-31 6:09 UTC (permalink / raw)
To: Phil Turmel; +Cc: linux-raid
Thank you for the reply Phil.
Unfortunately that didn't work, I get the following message:
root@Wheal-Peevor:~# mdadm --run /dev/md126
mdadm: failed to start array /dev/md126: Input/output error
Thanks
Peter
On 30 March 2016 at 23:17, Phil Turmel <philip@turmel.org> wrote:
> On 03/30/2016 05:19 PM, Peter Knight wrote:
>> Hi,
>>
>> I hope someone can explain what is going on and hopefully help me
>> recover my data.
>
>> What is causing this? and how can I get it reassembled so I can read the data?
>
> When mdadm assembles an array during boot that has fewer devices than
> when it was last shut down (cleanly), it generally declines to start it.
>
> Probably, all you need is:
>
> mdadm --run /dev/md126
>
> { --detail may not be accurate on an inactive device. The member
> --examine data is trustworthy. }
>
> Phil
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: Raid 6 failing to assemble after machine power loss now, with 1 disk only failed, seems to think its a raid0 array
2016-03-31 6:09 ` Peter Knight
@ 2016-03-31 7:01 ` Adam Goryachev
0 siblings, 0 replies; 4+ messages in thread
From: Adam Goryachev @ 2016-03-31 7:01 UTC (permalink / raw)
To: Peter Knight, Phil Turmel; +Cc: linux-raid
Try the following:
mdadm --stop /dev/md126
Check /proc/mdstat and make sure there is nothing there
Check dmesg output and note the last line, you will need to paste
everything after this line into your next email
madam --assemble /dev/md126 /dev/sd[abcdef]1
Adjust the devices listed above as applicable
Post the output of the above command, the dmesg output, and also
/proc/mdstat afterwards.
You can also try stopping the array/clearing it again, and then try
adding --force to the above command. Make sure to post the results.
Regards,
Adam
On 31/03/2016 17:09, Peter Knight wrote:
> Thank you for the reply Phil.
>
> Unfortunately that didn't work, I get the following message:
>
>
> root@Wheal-Peevor:~# mdadm --run /dev/md126
> mdadm: failed to start array /dev/md126: Input/output error
>
>
> Thanks
>
> Peter
>
> On 30 March 2016 at 23:17, Phil Turmel <philip@turmel.org> wrote:
>> On 03/30/2016 05:19 PM, Peter Knight wrote:
>>> Hi,
>>>
>>> I hope someone can explain what is going on and hopefully help me
>>> recover my data.
>>> What is causing this? and how can I get it reassembled so I can read the data?
>> When mdadm assembles an array during boot that has fewer devices than
>> when it was last shut down (cleanly), it generally declines to start it.
>>
>> Probably, all you need is:
>>
>> mdadm --run /dev/md126
>>
>> { --detail may not be accurate on an inactive device. The member
>> --examine data is trustworthy. }
>>
>> Phil
> --
> To unsubscribe from this list: send the line "unsubscribe linux-raid" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2016-03-31 7:01 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2016-03-30 21:19 Raid 6 failing to assemble after machine power loss now, with 1 disk only failed, seems to think its a raid0 array Peter Knight
2016-03-30 22:17 ` Phil Turmel
2016-03-31 6:09 ` Peter Knight
2016-03-31 7:01 ` Adam Goryachev
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox