[Ocfs2-users] OCFS2 and Snapshots

[Andre Brinkmann]

Hello Alexei,

yes I am sure :-). We have developed the software at our research lab 
and it has been extensively tested in productive environments for most 
Linux distributions and kernel versions (2.4.21 - 2.6.17). Up to now, we 
have mostly used it with single server file systems like XFS, Ext2, or 
Reiser.

Even if OCFS2 is still new, it has the advantages that it is really open 
source and it is not bound to a single distribution. But it misses some 
features which strongly simplify administration and data safety. 
Therefore I would like to couple OCFS2 with the features of our 
virtualization environment.

Similar to OCFS2, XFS relies on the uniqueness of a serial number. But 
with XFS, I am able to change this uid with a user space admin tool. I 
hope to find (or implement) similar features in OCFS2 to be able to 
support snapshots. I think the possibility to change the uuid is import 
for most storage system. Even hardware RAIDs with integrated snapshots 
will have similar problems.

Best Regards

Andre

Alexei_Roudnev wrote:
> Are you sure, that your snapshort/mirroring software can work on the cluster
> (shared disks)? I do not know such tools, except parts of Poliserver file
> system and (possible, with serious limitation) Veritas Volume Manager.
>
> OCFSv2 is new and not matured by itself; don't add extra instability into
> it.
>
>
> ----- Original Message ----- 
> From: "Andre Brinkmann" <brinkman at hni.upb.de>
> To: <ocfs2-users at oss.oracle.com>
> Sent: Thursday, July 20, 2006 8:39 AM
> Subject: [Ocfs2-users] OCFS2 and Snapshots
>
>
> Hello,
>
> I am trying to couple OCFS2 with a storage virtualization environment to
> use features like mirroring and snapshots. Unfortunately it seems to be
> impossible for ocfs2console (and for mount.ocfs2) to distinguish between
> the original volume and its snapshot and ocffs2 stops the mount-process
> with the following messages:
>
> Jul 20 17:23:54 sinalco kernel: (5028,1):ocfs2_initialize_super:1395
> max_slots for this device: 4
> Jul 20 17:23:54 sinalco kernel: (5028,0):ocfs2_fill_super:642 ERROR:
> Unable to create per-mount debugfs root.
>
> Is it possible too change the uuid and other relevant parameters?
>
> Best Regards
>
> André