Re: Possible to mount this XFS at least temporarily to retrieve files?

[Carsten Aulbert <carsten.aulbert@aei.mpg.de>]

Hi Dave and all others who replied,

I just realized I have not answered on list to thank you all for the
analysis of his failure!

On 10/25/17 23:29, Dave Chinner wrote:
> 
> This is a pretty good indication that the RAID rebuild has
> completely jumbled up the disks and the data on the disks during
> the rebuild.

*sigh*

> It's a hardware raid controller that is having hardware problems
> during a rebuild.  I'd say your filesystem is completely screwed
> because the rebuild went wrong and you have no way of knowing what
> blocks are good and what aren't, nor even whether the RAID has been
> assembled correctly after the failure. Hence even if you could mount
> it, the data in the files is likely to be corrupt/incorrect
> anyway...

We will now replace these controllers with dumb SAS HBA and will try to
keep the "raid" features at a different level (md+xfs and/or zfs) which
hopefully will avoid this failure mode in the future.

Until then, I think we are lucky as we do not have hot spares defined on
these controllers as that would prohibit us to react properly and
eliminate host I/O at a time of our choosing...

Thanks a lot again!

Cheers

Carsten

-- 
Dr. Carsten Aulbert, Max Planck Institute for Gravitational Physics,
Callinstraße 38, 30167 Hannover, Germany
Phone: +49 511 762 17185