xfs_repair of critical volume

[Martin Steigerwald]

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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