[Linux-cluster] GFS Tunables

[Gordan Bobic]

Brandon Young wrote:

> As for LVM snapshotting ... I am under the impression that those 
> features are unavailable in GFS (and are slated for GFS2?  Which is not 
> "production ready", yet?)  It has certainly occured to me to try that 
> feature, if only it were available.  Am I misinformed?  Perhaps I need 
> some more education on how exactly LVM mirroring will help me.  I am 
> *attempting* to approximate a traditional backup scheme, atleast on this 
> particular filesystem.  Am I correct in believing that I could snapshot 
> a volume (assuming the feature is available) and run a traditional 
> backup (using, say, rdiff-backup) in a shorter time than I can now, 
> where I'm running it straight off a live GFS volume?

You can use CLVM (Cluser aware LVM) and create GFS on top of that 
volume. You can them use CLVM to take a snapshot of the block device, 
mount it read-only with lock_nolock and back that up. That should go at 
non-clustered FS speeds.

Gordan