[Linux-cluster] GFS Tunables

[Gordan Bobic]

Kevin Anderson wrote:
> On Thu, 2008-10-16 at 21:29 +0100, Gordan Bobic wrote:
>> 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.
>>
> We don't have support for cluster snapshots as of yet even though it has
> been on the todo list for about 5 years now :(.

Joy... My mistake. Sorry I mentioned it.

Gordan