On 7/3/11 11:34 PM, kkeller@xxxxxxxxx wrote: > > > On Sun 03/07/11 3:14 PM , Eric Sandeen <sandeen@xxxxxxxxxxx> wrote: > > [some rearranging] > >> You're welcome but here's the obligatory plug in return - running >> RHEL5 proper would have gotten you up to date, fully supported xfs, >> and you wouldn't have run into this mess. Just sayin' ... ;) > > Yep, that's definitely a lesson learned. Though I don't think I can > blame CentOS either--from what I can tell the bug has been available > from yum for some time now. So it's pretty much entirely my own > fault. :( well it's unfortunate that that kmod persists. I'll admit to providing it, years and years ago... Centos should find a way to deprecate it... > I also am sorry for not preserving threading--for some reason, the > SGI mailserver rejected mail from my normal host (which is odd, as > it's not in any blacklists I know of), so I am using an unfamiliar > mail client. sgi email ... sucks ;) >> You probably hit this bug: >> http://oss.sgi.com/archives/xfs/2007-01/msg00053.html [1] >> >> See also: http://oss.sgi.com/archives/xfs/2009-07/msg00087.html >> [2] >> >> I can't remember how much damage the original bug did ... > > If any? I'm a bit amazed that, if there was damage, that the > filesystem is still usable. Perhaps if I were to fill it it would > show signs of inconsistency? Or remounting would read the > now-incorrect values from the superblock 0? > >> is it still mounted I guess? > > Yes, it's still mounted, and as far as I can tell perfectly fine. > But I won't really know till I can throw xfs_repair -n and/or xfs_db > and/or remount it; I'm choosing to get as much data off as I can > before I try these things, just in case. > > How safe is running xfs_db with -r on my mounted filesystem? I it's safe. At worst it might read inconsistent data, but it's perfectly safe. > understand that results might not be consistent, but on the off > chance that they are I am hoping that it might be at least a little > helpful. > > I was re-reading some of the threads I posted in my original > messages, in particular these posts: > > http://oss.sgi.com/archives/xfs/2009-09/msg00210.html > http://oss.sgi.com/archives/xfs/2009-09/msg00211.html > > If I am reading those, plus the xfs_db man page, correctly, it seems > like what Russell suggested was to look at superblock 1 (or some > other one?) and use those values to correct superblock 0. At what don't worry about correcting anything until you know there is a problem :) > points (if any) are the other superblocks updated? I was testing on > another machine, on a filesystem that I had successfully grown using > xfs_growfs, and of the two values Russell suggested the OP to change, > dblocks is different between sb 0 and sb 1, but agcount is not. > Could that just be that I did not grow the filesystem too much, so > that agcount didn't need to change? That seems a bit > counterintuitive, but (as should be obvious) I don't know XFS all if you grew it 9T, you would have almost certainly gotten more AGs. If you did a smaller test then you might see that. To be honest I don't remember when the backup superblocks get updated. > that well. I am hoping to know because, in re-reading those > messages, I got a better idea of what those particular xfs_db > commands do, so that if I did run into problems remounting, I might > be able to determine the appropriate new values myself and reduce my > downtime. But I want to understand more what I'm doing before I try > that! I think finding a way to do a dry-run xfs_repair would be the best place to start ... Get a recent xfsprogs too, if you haven't already, it scales better than the really old versions. -Eric > --keith > _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
