[linux-lvm] Re: lvextend error on XFS

[Måns Rullgård]

"Frank J. Buchholz" <frankb at ercwc.org> writes:

>> "Frank J. Buchholz" <frankb ercwc org> writes:
>>
>>> Hello,
>>>
>>> I recently attempted to extend my logical volume.  First I added an
>>> additional physical volume to an existing volume group.  This worked
>>> fine.
>>>
>>> vgextend Volume00 /dev/sba
>>> lvextend -L+100G /dev/Volume00/LogVol00
>>>
>>> However when it came time to run the lvextend command I received a
>>> number of  device-mapper errors.  While I was trying to determine what
>>> the errors were I noticed that the filesystem that sits on the logical
>>> volume being extended was no longer available.  I attempted to umount
>>> the filesystem however the command froze.  I then rebooted the system
>>> without mounting the filesystem in question and manually mounted the
>>> filesystem. XFS reported back that it could not locate the superblock.
>>
>> I have done lvextend followed by xfs_growfs many times without any
>> problems.  Have you checked for hardware errors?
>
> Unfortunately the timing is far too coincidental to be a hardware error.

Since you had just added another disk, it may not be so coincidental
after all.

> Just after typing the following command and recieving the following error
> lvm> lvextend -L+1G /dev/Volume00/LogVol00
>   Extending logical volume LogVol00 to 2.93 TB
>   device-mapper ioctl cmd 9 failed: Invalid argument
>   Couldn't load device 'Volume00-LogVol00'.
>   Problem reactivating LogVol00

The last line would explain why the filesystem went offline.
Something went wrong just after the LV had been extended, and was
about to be reactivated.

> I then noticed that the filesystem on LogVol00 was no longer available
> and when I ran xfs_repair it stated the following:
> # xfs_repair /dev/Volume00/LogVol00 
> Phase 1 - find and verify superblock...
> superblock read failed, offset 0, size 524288, ag 0, rval 0
>
> fatal error -- Invalid argument

What does "dmesg" have to say about this?

I had a problem once with some strange errors from a disk.  It turned
out the cable wasn't plugged in properly.

-- 
Måns Rullgård
mru at inprovide.com