xfs
[Top] [All Lists]

Re: problem after growing

To: Rémi Cailletaud <remi.cailletaud@xxxxxxxxxxxxxxx>
Subject: Re: problem after growing
From: Eric Sandeen <sandeen@xxxxxxxxxxx>
Date: Wed, 13 Feb 2013 14:12:38 -0600
Cc: xfs-oss <xfs@xxxxxxxxxxx>
Delivered-to: xfs@xxxxxxxxxxx
In-reply-to: <511BEE8B.8000400@xxxxxxxxxxx>
References: <511BC78B.6070205@xxxxxxxxxxxxxxx> <511BCB41.4060804@xxxxxxxxxxx> <511BCD11.20907@xxxxxxxxxxxxxxx> <511BCFB6.8000309@xxxxxxxxxxx> <511BD0FB.2070401@xxxxxxxxxxxxxxx> <511BD2D1.9010906@xxxxxxxxxxx> <511BD6ED.6030006@xxxxxxxxxxxxxxx> <511BEE8B.8000400@xxxxxxxxxxx>
User-agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:17.0) Gecko/20130107 Thunderbird/17.0.2
On 2/13/13 1:50 PM, Eric Sandeen wrote:
> On 2/13/13 12:09 PM, Rémi Cailletaud wrote:
>> Le 13/02/2013 18:52, Eric Sandeen a écrit :
> 
> <snip>
> 
>>> Did the filesystem grow actually work?
>>>
>>> # xfs_db -c "sb 0" -c "p" /dev/vg0/tomo-201111
>>> magicnum = 0x58465342
>>> blocksize = 4096
>>> dblocks = 10468982745
>>>
>>> That looks like it's (still?) a 38TiB/42TB filesystem, with:
>>>
>>> sectsize = 512
>>>
>>> 512 sectors.
>>>
>>> How big was it before you tried to grow it, and how much did you try to 
>>> grow it by?  Maybe the size never changed.
>>
>> Was 39, growing to 44. Testdisk says 48 TB / 44 TiB... There is some chance 
>> that it was never really growed.
>>> At mount time it tries to set the sector size of the device; its' a hard-4k 
>>> device, so setting it to 512 fails.
>>>
>>> This may be as much of an LVM issue as anything; how do you get the LVM 
>>> device back to something with 512-byte logical sectors?  I have no idea...
>>>
>>> *if* the fs didn't actually grow, and if the new 4k-sector space is not 
>>> used by the filesystem, and if you can somehow remove that new space from 
>>> the device and set the LV back to 512 sectors, you might be in good shape.
>> I dont either know how to see nor set LV sector size.  It's 100% sure that 
>> anything was copied on 4k sector size, and pretty sure that the fs did not 
>> really grow.
> 
> I think the same blockdev command will tell you.
> 
>  
>>> Proceed with extreme caution here, I wouldn't start just trying random 
>>> things unless you have some other way to get your data back (backups?).  
>>> I'd check with LVM folks as well, and maybe see if dchinner or the sgi 
>>> folks have other suggestions.
>> Sigh... No backup (44To is too large for us...) ! I'm running a testdisk 
>> recover, but I'm not very confident about success...
>> Thanks to deeper investigate this...
>>> First let's find out if the filesystem actually thinks it's living on the 
>>> new space.
>> What is the way to make it talk about that ?
> 
> well, you have 10468982745 4k blocks in your filesystem, so 42880953323520 
> bytes of xfs filesystem.
> 
> Look at your lvm layout, does that extend into the new disk space or is it 
> confined to the original disk space?

lvm folks I talk to say that if you remove the 4k device from the lvm volume it 
should switch back to 512 sectors.

so if you can can convince yourself that 42880953323520 bytes does not cross 
into the newly added disk space, just remove it again, and everything should be 
happy.

Unless your rash decision to start running "testdisk" made things worse ;)

-Eric

> -Eric
> 
>> Thanks again for your help !
>>
>> rémi
>>
>>> -Eric
>>>
>>>> rémi

<Prev in Thread] Current Thread [Next in Thread>