Re: xfs_repair of critical volume

Martin Steigerwald
2010-12-04T10:28:40Z

Am Freitag 12 November 2010 schrieb Stan Hoeppner:
> Michael Monnerie put forth on 11/12/2010 7:22 AM:
> > I find the robustness of XFS amazing: You overwrote 1/5th of the disk
> > with zeroes, and it still works :-)
>
> This isn't "robustness" Michael. If anything it's a serious problem.
> XFS is reporting that hundreds or thousands of files that have been
> physically removed still exist. Regardless of how he arrived at this
> position, how is this "robust"? Most people would consider this
> inconsistency of state a "corruption" situation, not "robustness".

I think its necessary to differentiate here:

1) It appears to be robustness - or pure luck - regarding metadata
consistency of the filesystem. I tend to believe its pure luck and that XFS
just stored the metadata on the other RAID arrays.

2) XFS does not seem to have a way to detect whether file contents are
still valid and consistent. It shares that with I think every other Linux
filesystem instead BTRFS which uses checksumming for files. (Maybe NILFS as
well, I don't know, and the FUSE or the other ZFS port).

Ciao,
--
Martin 'Helios' Steigerwald - http://www.Lichtvoll.de
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