linux-raid.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* unused space before data offset mismatch
@ 2013-11-20 19:46 kustep
  2013-11-21  3:25 ` Phil Turmel
  2013-11-21  3:33 ` NeilBrown
  0 siblings, 2 replies; 3+ messages in thread
From: kustep @ 2013-11-20 19:46 UTC (permalink / raw)
  To: linux-raid

Hello Everyone,

is there an option to specifiy the "Unused Space : before=...."
Superblock information in mdadm -C ....?

My Raid crashed due to a controller error, but I was able to make the
new superblock almost identical to the old one (using mdadm -C
--assume-clean --level=6 --raid-devices=11 --chunk=256K --metadata=1.2
--bitmap=None --size=195328588 --data-offset=128768 /dev/md0
/dev/mapper/disk[cdefmbjkh] missing). Looking at mdadm --examine the
only difference left is:
old layout: Unused Space : before=257456 sectors, after=197632 sectors
new layout: Unused Space : before=257448 sectors, after=197632 sectors

Is there an option to change that or anything else I can do to make the
layouts identical? The assembled raid refuses to mount, and I suspect
this difference to be the reason.

Thanks in advance
Stephan

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: unused space before data offset mismatch
  2013-11-20 19:46 unused space before data offset mismatch kustep
@ 2013-11-21  3:25 ` Phil Turmel
  2013-11-21  3:33 ` NeilBrown
  1 sibling, 0 replies; 3+ messages in thread
From: Phil Turmel @ 2013-11-21  3:25 UTC (permalink / raw)
  To: kustep, linux-raid

On 11/20/2013 02:46 PM, kustep wrote:
> Hello Everyone,
> 
> is there an option to specifiy the "Unused Space : before=...."
> Superblock information in mdadm -C ....?

I don't know about this, but ...

> My Raid crashed due to a controller error, but I was able to make the
> new superblock almost identical to the old one (using mdadm -C
> --assume-clean --level=6 --raid-devices=11 --chunk=256K --metadata=1.2
> --bitmap=None --size=195328588 --data-offset=128768 /dev/md0
> /dev/mapper/disk[cdefmbjkh] missing). Looking at mdadm --examine the

This almost certainly didn't do what you think--square brackets in the
shell don't maintain the order of the letters given.  The device order
actually given to mdadm would have been [bcdefhjkm].  The bracket
notation will also leave out devices that don't actually exist.  You
need to use curly braces with commas to maintain a specific order.

FWIW,

Phil

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: unused space before data offset mismatch
  2013-11-20 19:46 unused space before data offset mismatch kustep
  2013-11-21  3:25 ` Phil Turmel
@ 2013-11-21  3:33 ` NeilBrown
  1 sibling, 0 replies; 3+ messages in thread
From: NeilBrown @ 2013-11-21  3:33 UTC (permalink / raw)
  To: kustep; +Cc: linux-raid

[-- Attachment #1: Type: text/plain, Size: 1304 bytes --]

On Wed, 20 Nov 2013 20:46:21 +0100 kustep <kustep@web.de> wrote:

> Hello Everyone,
> 
> is there an option to specifiy the "Unused Space : before=...."
> Superblock information in mdadm -C ....?

 --data-offset=....

or 
  --data-offset=variable ... /dev/foo:16K  /dev/foo2:32K ....

You probably need mdadm 3.3.

NeilBrown

> 
> My Raid crashed due to a controller error, but I was able to make the
> new superblock almost identical to the old one (using mdadm -C
> --assume-clean --level=6 --raid-devices=11 --chunk=256K --metadata=1.2
> --bitmap=None --size=195328588 --data-offset=128768 /dev/md0
> /dev/mapper/disk[cdefmbjkh] missing). Looking at mdadm --examine the
> only difference left is:
> old layout: Unused Space : before=257456 sectors, after=197632 sectors
> new layout: Unused Space : before=257448 sectors, after=197632 sectors
> 
> Is there an option to change that or anything else I can do to make the
> layouts identical? The assembled raid refuses to mount, and I suspect
> this difference to be the reason.
> 
> Thanks in advance
> Stephan
> --
> 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


[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 828 bytes --]

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2013-11-21  3:33 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2013-11-20 19:46 unused space before data offset mismatch kustep
2013-11-21  3:25 ` Phil Turmel
2013-11-21  3:33 ` NeilBrown

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).