* Reassemble Raid 6
@ 2014-02-10 16:48 Justin Stephenson
2014-02-10 20:53 ` Phil Turmel
0 siblings, 1 reply; 4+ messages in thread
From: Justin Stephenson @ 2014-02-10 16:48 UTC (permalink / raw)
To: linux-raid
Hello,
I have reviewed the Linux Raid Wiki regarding rebuilding and it
recommended writing a note to the list.
I am running an mdadm raid on CENTOS 6.5 with 6 disks in a Raid 6 off of
my motherboard's SATA controller.
I added a 7th disk as a spare.
When I rebooted the raid after adding the spare, it would not mount and
the OS would only boot into recovery mode. I changed my fsck file to
exclude the raid and can now boot into the GUI.
I have tried to reassemble the array using --assemble and I get the the
following message:
mdadm: we match both /dev/md/BigBlue:0 and /dev/md0 - cannot decide
which to use.
I am including the output of the mdadm --examine below.
I am considering using --force to assemble the array, though I suspect
that this is something simple that I am overlooking -- I am quite new to
linux.
Any input would be appreciated.
- Justin
/dev/sdb1:
Magic : a92b4efc
Version : 1.2
Feature Map : 0x0
Array UUID : 0849c677:64e4772e:8892d80b:47e0097a
Name : BigBlue:0 (local to host BigBlue)
Creation Time : Wed Jan 15 22:46:32 2014
Raid Level : raid6
Raid Devices : 6
Avail Dev Size : 5860267024 (2794.39 GiB 3000.46 GB)
Array Size : 11720533504 (11177.57 GiB 12001.83 GB)
Used Dev Size : 5860266752 (2794.39 GiB 3000.46 GB)
Data Offset : 262144 sectors
Super Offset : 8 sectors
State : clean
Device UUID : 7f7ace48:01a4b6f6:bf182ae3:6acddef9
Update Time : Sun Feb 9 20:31:13 2014
Checksum : cedf7f63 - correct
Events : 557
Layout : left-symmetric
Chunk Size : 128K
Device Role : spare
Array State : AAAAAA ('A' == active, '.' == missing)
/dev/sdc1:
Magic : a92b4efc
Version : 1.2
Feature Map : 0x0
Array UUID : 0849c677:64e4772e:8892d80b:47e0097a
Name : BigBlue:0 (local to host BigBlue)
Creation Time : Wed Jan 15 22:46:32 2014
Raid Level : raid6
Raid Devices : 6
Avail Dev Size : 5860267024 (2794.39 GiB 3000.46 GB)
Array Size : 11720533504 (11177.57 GiB 12001.83 GB)
Used Dev Size : 5860266752 (2794.39 GiB 3000.46 GB)
Data Offset : 262144 sectors
Super Offset : 8 sectors
State : clean
Device UUID : 8a4d11bd:fe387740:1edc1151:b0ebba43
Update Time : Sun Feb 9 20:31:13 2014
Checksum : 44a6c909 - correct
Events : 557
Layout : left-symmetric
Chunk Size : 128K
Device Role : Active device 0
Array State : AAAAAA ('A' == active, '.' == missing)
/dev/sdd1:
Magic : a92b4efc
Version : 1.2
Feature Map : 0x0
Array UUID : 0849c677:64e4772e:8892d80b:47e0097a
Name : BigBlue:0 (local to host BigBlue)
Creation Time : Wed Jan 15 22:46:32 2014
Raid Level : raid6
Raid Devices : 6
Avail Dev Size : 5860267024 (2794.39 GiB 3000.46 GB)
Array Size : 11720533504 (11177.57 GiB 12001.83 GB)
Used Dev Size : 5860266752 (2794.39 GiB 3000.46 GB)
Data Offset : 262144 sectors
Super Offset : 8 sectors
State : clean
Device UUID : aa158e32:f4449a9b:73e95000:22852278
Update Time : Sun Feb 9 20:31:13 2014
Checksum : f8ed43e6 - correct
Events : 557
Layout : left-symmetric
Chunk Size : 128K
Device Role : Active device 1
Array State : AAAAAA ('A' == active, '.' == missing)
/dev/sde1:
Magic : a92b4efc
Version : 1.2
Feature Map : 0x0
Array UUID : 0849c677:64e4772e:8892d80b:47e0097a
Name : BigBlue:0 (local to host BigBlue)
Creation Time : Wed Jan 15 22:46:32 2014
Raid Level : raid6
Raid Devices : 6
Avail Dev Size : 5860267024 (2794.39 GiB 3000.46 GB)
Array Size : 11720533504 (11177.57 GiB 12001.83 GB)
Used Dev Size : 5860266752 (2794.39 GiB 3000.46 GB)
Data Offset : 262144 sectors
Super Offset : 8 sectors
State : clean
Device UUID : 7bee5d42:cb66c602:162e88f1:e140447c
Update Time : Sun Feb 9 20:31:13 2014
Checksum : 65423ef2 - correct
Events : 557
Layout : left-symmetric
Chunk Size : 128K
Device Role : Active device 2
Array State : AAAAAA ('A' == active, '.' == missing)
/dev/sdf1:
Magic : a92b4efc
Version : 1.2
Feature Map : 0x0
Array UUID : 0849c677:64e4772e:8892d80b:47e0097a
Name : BigBlue:0 (local to host BigBlue)
Creation Time : Wed Jan 15 22:46:32 2014
Raid Level : raid6
Raid Devices : 6
Avail Dev Size : 5860267024 (2794.39 GiB 3000.46 GB)
Array Size : 11720533504 (11177.57 GiB 12001.83 GB)
Used Dev Size : 5860266752 (2794.39 GiB 3000.46 GB)
Data Offset : 262144 sectors
Super Offset : 8 sectors
State : clean
Device UUID : b4a7b35c:6e377711:4b291874:edb2c4d0
Update Time : Sun Feb 9 20:31:13 2014
Checksum : 65593610 - correct
Events : 557
Layout : left-symmetric
Chunk Size : 128K
Device Role : Active device 3
Array State : AAAAAA ('A' == active, '.' == missing)
/dev/sdg1:
Magic : a92b4efc
Version : 1.2
Feature Map : 0x0
Array UUID : 0849c677:64e4772e:8892d80b:47e0097a
Name : BigBlue:0 (local to host BigBlue)
Creation Time : Wed Jan 15 22:46:32 2014
Raid Level : raid6
Raid Devices : 6
Avail Dev Size : 5860267024 (2794.39 GiB 3000.46 GB)
Array Size : 11720533504 (11177.57 GiB 12001.83 GB)
Used Dev Size : 5860266752 (2794.39 GiB 3000.46 GB)
Data Offset : 262144 sectors
Super Offset : 8 sectors
State : clean
Device UUID : 7c0bba5a:6b205302:d026a78d:91f5ebdd
Update Time : Sun Feb 9 20:31:13 2014
Checksum : 7af1c2ff - correct
Events : 557
Layout : left-symmetric
Chunk Size : 128K
Device Role : Active device 4
Array State : AAAAAA ('A' == active, '.' == missing)
/dev/sdh1:
Magic : a92b4efc
Version : 1.2
Feature Map : 0x0
Array UUID : 0849c677:64e4772e:8892d80b:47e0097a
Name : BigBlue:0 (local to host BigBlue)
Creation Time : Wed Jan 15 22:46:32 2014
Raid Level : raid6
Raid Devices : 6
Avail Dev Size : 5860267024 (2794.39 GiB 3000.46 GB)
Array Size : 11720533504 (11177.57 GiB 12001.83 GB)
Used Dev Size : 5860266752 (2794.39 GiB 3000.46 GB)
Data Offset : 262144 sectors
Super Offset : 8 sectors
State : clean
Device UUID : a750a146:7ee7383e:2929d803:2bee9dc1
Update Time : Sun Feb 9 20:31:13 2014
Checksum : fca1ca30 - correct
Events : 557
Layout : left-symmetric
Chunk Size : 128K
Device Role : Active device 5
Array State : AAAAAA ('A' == active, '.' == missing)
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: Reassemble Raid 6
2014-02-10 16:48 Reassemble Raid 6 Justin Stephenson
@ 2014-02-10 20:53 ` Phil Turmel
2014-02-11 0:13 ` Re[2]: " Justin Stephenson
0 siblings, 1 reply; 4+ messages in thread
From: Phil Turmel @ 2014-02-10 20:53 UTC (permalink / raw)
To: Justin Stephenson, linux-raid
On 02/10/2014 11:48 AM, Justin Stephenson wrote:
> Hello,
>
> I have reviewed the Linux Raid Wiki regarding rebuilding and it
> recommended writing a note to the list.
>
> I am running an mdadm raid on CENTOS 6.5 with 6 disks in a Raid 6 off of
> my motherboard's SATA controller.
>
> I added a 7th disk as a spare.
>
> When I rebooted the raid after adding the spare, it would not mount and
> the OS would only boot into recovery mode. I changed my fsck file to
> exclude the raid and can now boot into the GUI.
>
> I have tried to reassemble the array using --assemble and I get the the
> following message:
>
> mdadm: we match both /dev/md/BigBlue:0 and /dev/md0 - cannot decide
> which to use.
Please show the output of your mdadm.conf file, and the complete command
you used to assemble with. Add "-v" to it to show more information.
{There's nothing wrong with your array, just conflicting info in your
configuration file.}
Phil
^ permalink raw reply [flat|nested] 4+ messages in thread* Re[2]: Reassemble Raid 6
2014-02-10 20:53 ` Phil Turmel
@ 2014-02-11 0:13 ` Justin Stephenson
2014-02-10 23:02 ` Phil Turmel
0 siblings, 1 reply; 4+ messages in thread
From: Justin Stephenson @ 2014-02-11 0:13 UTC (permalink / raw)
To: Phil Turmel, linux-raid
Hello Phil,
You are 100% correct. Thanks for your email. I had 2 separate ARRAY
entries in my mdadm.config file. When I added the spare, I added the new
information to the config file but did not remove the old entry. Total
newbie mistake.
- I commented out all the previous entries in the mdadm.config file (it
had a devices lists instead of the UUID information)
- I successfully assembled the array (mdadm --assemble /dev/md0
/dev/sdb1 etc...)
- I updated the config file using the information from mdadm -Esc
partitions | grep UUID and deleted the old entries.
- I uncommented the fstab entry for the array and rebooted.
Everything is working perfectly now.
I remember reading somewhere that mdadm can run without the config file
by using the RAID uuid and the information in the superblocks. Would
this be more reliable?
Thanks Again,
- Justin
------ Original Message ------
From: "Phil Turmel" <philip@turmel.org>
To: "Justin Stephenson" <justin@evensteveninc.com>;
linux-raid@vger.kernel.org
Sent: 10/02/2014 12:53:31 PM
Subject: Re: Reassemble Raid 6
>On 02/10/2014 11:48 AM, Justin Stephenson wrote:
>> Hello,
>>
>> I have reviewed the Linux Raid Wiki regarding rebuilding and it
>> recommended writing a note to the list.
>>
>> I am running an mdadm raid on CENTOS 6.5 with 6 disks in a Raid 6 off
>>of
>> my motherboard's SATA controller.
>>
>> I added a 7th disk as a spare.
>>
>> When I rebooted the raid after adding the spare, it would not mount
>>and
>> the OS would only boot into recovery mode. I changed my fsck file to
>> exclude the raid and can now boot into the GUI.
>>
>> I have tried to reassemble the array using --assemble and I get the
>>the
>> following message:
>>
>> mdadm: we match both /dev/md/BigBlue:0 and /dev/md0 - cannot decide
>> which to use.
>
>Please show the output of your mdadm.conf file, and the complete
>command
>you used to assemble with. Add "-v" to it to show more information.
>
>{There's nothing wrong with your array, just conflicting info in your
>configuration file.}
>
>Phil
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: Reassemble Raid 6
2014-02-11 0:13 ` Re[2]: " Justin Stephenson
@ 2014-02-10 23:02 ` Phil Turmel
0 siblings, 0 replies; 4+ messages in thread
From: Phil Turmel @ 2014-02-10 23:02 UTC (permalink / raw)
To: Justin Stephenson, linux-raid
On 02/10/2014 07:13 PM, Justin Stephenson wrote:
> Hello Phil,
>
> You are 100% correct. Thanks for your email. I had 2 separate ARRAY
> entries in my mdadm.config file. When I added the spare, I added the new
> information to the config file but did not remove the old entry. Total
> newbie mistake.
>
> - I commented out all the previous entries in the mdadm.config file (it
> had a devices lists instead of the UUID information)
>
> - I successfully assembled the array (mdadm --assemble /dev/md0
> /dev/sdb1 etc...)
>
> - I updated the config file using the information from mdadm -Esc
> partitions | grep UUID and deleted the old entries.
>
> - I uncommented the fstab entry for the array and rebooted.
>
>
> Everything is working perfectly now.
>
>
> I remember reading somewhere that mdadm can run without the config file
> by using the RAID uuid and the information in the superblocks. Would
> this be more reliable?
>
> Thanks Again
You're welcome.
I suggest you trim the mdadm.conf file even further--I only specify name
and uuid, so device changes don't interfere with assembly. Like so
(slightly edited):
MAILFROM mdadm@example.com
MAILADDR philip@example.com
DEVICE /dev/sd[a-z][1-9]
# Mirrored Boot partitions
ARRAY /dev/md1 UUID=75c011c6:caeb06ea:ec7e3370:aa4f3320
# Far mirror (Raid10) core operations
ARRAY /dev/md2 UUID=6b4858da:f24e2567:34e73fe5:b8f2c118
# Bulk redundant (Raid6) storage
ARRAY /dev/md3 UUID=04f3706c:79a3cd73:8a558eee:93ec1879
HTH,
Phil
ps. Don't forget to update your initramfs after any changes to mdadm.conf!
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2014-02-11 0:13 UTC | newest]
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2014-02-10 16:48 Reassemble Raid 6 Justin Stephenson
2014-02-10 20:53 ` Phil Turmel
2014-02-11 0:13 ` Re[2]: " Justin Stephenson
2014-02-10 23:02 ` Phil Turmel
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