[Linux-cluster] strange GFS problem

[David Teigland]

On Wed, Jun 15, 2005 at 06:41:39AM -0700, Igor wrote:
> > Eventually you should be able to combine gnbd with
> > cluster mirroring
> > to do this sort of thing.  Not possible yet, though.
> 
> Rats.
> 
> What if I do this:
> 
> Two machines alice (HDs 1 & 2) & bob (HDs 3 & 4).
> 
> I gnbd export 2 to bob and 4 to alice.  Then I LVM
> mirror 2 & 4 on both alice & bob.  Then GFS on top of
> that.
> 
> Will that work?

When we have cluster mirroring in lvm it should.  Normal (non-clustered)
mirroring was just introduced in lvm this week.  I think the only
substantive difference with cluster-mirroring is synchronizing updates to
the dirty region log, and then how mirror resync is done using the log.

In theory, you might be able to make your idea work with normal mirroring
if you cut out the dirty region logging altogether.  If you're up for
experimenting it would be interesting to try.

Dave