From: "Matthew Tice" <mjtice@gmail.com>
To: linux-raid@vger.kernel.org
Subject: RE: Removed two drives (still valid and working) from raid-5 and need to add them back in.
Date: Mon, 14 Mar 2011 06:29:50 -0600 [thread overview]
Message-ID: <000301cbe243$846419b0$8d2c4d10$@com> (raw)
In-Reply-To: <5EB70557-47EB-4F81-A158-4A5157EB7E37@gmail.com>
On Mar 12, 2011, at 8:56 PM, Phil Turmel wrote:
> On 03/12/2011 10:38 PM, mtice wrote:
>> Hi Phil, thanks for the reply.
>> Here is the output of mdadm -E /dev/sd[cdef]
>>
>> /dev/sdc:
>> Magic : a92b4efc
>> Version : 00.90.00
>> UUID : 11c1cdd8:60ec9a90:2e29483d:f114274d (local to host
storage)
>> Creation Time : Thu May 27 15:35:56 2010
>> Raid Level : raid5
>> Used Dev Size : 732574464 (698.64 GiB 750.16 GB)
>> Array Size : 2197723392 (2095.91 GiB 2250.47 GB)
>> Raid Devices : 4
>> Total Devices : 5
>> Preferred Minor : 0
>>
>> Update Time : Fri Mar 11 15:53:35 2011
>> State : clean
>> Active Devices : 2
>> Working Devices : 4
>> Failed Devices : 2
>> Spare Devices : 2
>> Checksum : 3d3b86 - correct
>> Events : 43200
>>
>> Layout : left-symmetric
>> Chunk Size : 64K
>>
>> Number Major Minor RaidDevice State
>> this 3 8 32 3 active sync /dev/sdc
>>
>> 0 0 8 80 0 active sync /dev/sdf
>> 1 1 0 0 1 faulty removed
>> 2 2 0 0 2 faulty removed
>> 3 3 8 32 3 active sync /dev/sdc
>> 4 4 8 64 4 spare /dev/sde
>> 5 5 8 112 5 spare
>> /dev/sdd:
>> Magic : a92b4efc
>> Version : 00.90.00
>> UUID : 11c1cdd8:60ec9a90:2e29483d:f114274d (local to host
storage)
>> Creation Time : Thu May 27 15:35:56 2010
>> Raid Level : raid5
>> Used Dev Size : 732574464 (698.64 GiB 750.16 GB)
>> Array Size : 2197723392 (2095.91 GiB 2250.47 GB)
>> Raid Devices : 4
>> Total Devices : 5
>> Preferred Minor : 0
>>
>> Update Time : Fri Mar 11 15:53:35 2011
>> State : clean
>> Active Devices : 2
>> Working Devices : 4
>> Failed Devices : 2
>> Spare Devices : 2
>> Checksum : 3d3bd4 - correct
>> Events : 43200
>>
>> Layout : left-symmetric
>> Chunk Size : 64K
>>
>> Number Major Minor RaidDevice State
>> this 5 8 112 5 spare
>>
>> 0 0 8 80 0 active sync /dev/sdf
>> 1 1 0 0 1 faulty removed
>> 2 2 0 0 2 faulty removed
>> 3 3 8 32 3 active sync /dev/sdc
>> 4 4 8 64 4 spare /dev/sde
>> 5 5 8 112 5 spare
>> /dev/sde:
>> Magic : a92b4efc
>> Version : 00.90.00
>> UUID : 11c1cdd8:60ec9a90:2e29483d:f114274d (local to host
storage)
>> Creation Time : Thu May 27 15:35:56 2010
>> Raid Level : raid5
>> Used Dev Size : 732574464 (698.64 GiB 750.16 GB)
>> Array Size : 2197723392 (2095.91 GiB 2250.47 GB)
>> Raid Devices : 4
>> Total Devices : 5
>> Preferred Minor : 0
>>
>> Update Time : Fri Mar 11 15:53:35 2011
>> State : clean
>> Active Devices : 2
>> Working Devices : 4
>> Failed Devices : 2
>> Spare Devices : 2
>> Checksum : 3d3ba2 - correct
>> Events : 43200
>>
>> Layout : left-symmetric
>> Chunk Size : 64K
>>
>> Number Major Minor RaidDevice State
>> this 4 8 64 4 spare /dev/sde
>>
>> 0 0 8 80 0 active sync /dev/sdf
>> 1 1 0 0 1 faulty removed
>> 2 2 0 0 2 faulty removed
>> 3 3 8 32 3 active sync /dev/sdc
>> 4 4 8 64 4 spare /dev/sde
>> 5 5 8 112 5 spare
>> /dev/sdf:
>> Magic : a92b4efc
>> Version : 00.90.00
>> UUID : 11c1cdd8:60ec9a90:2e29483d:f114274d (local to host
storage)
>> Creation Time : Thu May 27 15:35:56 2010
>> Raid Level : raid5
>> Used Dev Size : 732574464 (698.64 GiB 750.16 GB)
>> Array Size : 2197723392 (2095.91 GiB 2250.47 GB)
>> Raid Devices : 4
>> Total Devices : 5
>> Preferred Minor : 0
>>
>> Update Time : Fri Mar 11 15:53:35 2011
>> State : clean
>> Active Devices : 2
>> Working Devices : 4
>> Failed Devices : 2
>> Spare Devices : 2
>> Checksum : 3d3bb0 - correct
>> Events : 43200
>>
>> Layout : left-symmetric
>> Chunk Size : 64K
>>
>> Number Major Minor RaidDevice State
>> this 0 8 80 0 active sync /dev/sdf
>>
>> 0 0 8 80 0 active sync /dev/sdf
>> 1 1 0 0 1 faulty removed
>> 2 2 0 0 2 faulty removed
>> 3 3 8 32 3 active sync /dev/sdc
>> 4 4 8 64 4 spare /dev/sde
>> 5 5 8 112 5 spare
>>
>>
>> I ran mdadm --assemble --force /dev/md0 but it erred with:
>>
>> mdadm: device /dev/md0 already active - cannot assemble it
>
> You would have to stop the array first. But it won't matter. The dropped
devices don't remember their role. But you have a 50-50 chance of getting
it right. It's either:
>
> mdadm --create /dev/md0 --level=5 --raid-devices=4 --assume-clean
--metadata=0.90 --chunk=64k /dev/sdf /dev/sde /dev/sdd /dev/sdc
>
> or with /dev/sde and /dev/sdd swapped.
>
> I suggest you try it both ways, with an "fsck -n" to see which has a
consistent filesystem. Once you figure out which order is correct, do a
real fsck to fix up any minor errors from the inadvertent unplug, then mount
and grab a fresh backup.
>
> Let us know how it turns out (I'm about to sign off for the night...).
>
> Phil
That did it. Thanks, Phil!
I was able to get the drives added back in with:
mdadm --create /dev/md0 --level=5 --raid-devices=4 --assume-clean
--metadata=0.90 --chunk=64 /dev/sdf /dev/sde /dev/sdd /dev/sdc
An fsck -n came back clean so I ran another fsck and mounted it up and all
looks good.
Thanks for your help!
Matt
prev parent reply other threads:[~2011-03-14 12:29 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-03-12 19:12 Removed two drives (still valid and working) from raid-5 and need to add them back in mtice
2011-03-13 1:01 ` mtice
2011-03-13 3:26 ` Phil Turmel
2011-03-13 3:38 ` mtice
[not found] ` <4D7C4083.2010000@turmel.org>
2011-03-14 0:14 ` mtice
2011-03-14 12:29 ` Matthew Tice [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to='000301cbe243$846419b0$8d2c4d10$@com' \
--to=mjtice@gmail.com \
--cc=linux-raid@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.