[Ocfs2-users] Diagnosing some OCFS2 error messages

[Patrick J. LoPresti]

On Mon, Jun 14, 2010 at 7:22 AM, Brian Kroth <bpkroth at gmail.com> wrote:
>
> I don't believe OCFS2 can currently support any logical volume manager
> other than a simple concatenation (and even then it's with extreme
> caution).  The overhead involved in the lower software layer doing
> striping needs to somehow be coordinated among all the nodes in the
> cluster else all fs consistency guarantees provided by the SCSI layer
> are lost.

Hi, Brian, and thank you for your reply.

First, from what I have read, OCFS2 should work fine over any software
RAID that does not provide redundancy (i.e., concatenation or RAID-0
is fine; RAID-1 or RAID-5 is not).

Second, I saw similar results using cLVM2, which the Suse 11 SP1 say
should work with OCFS2 (integrated cluster stack).  At least, I am
pretty sure I saw similar results, but I forgot to capture the logs so
I am not 100% certain.

Finally, I ran that "fsck,.ocfs2" from a single node while the md
device unmounted on all nodes, and it gave me an "I/O error".  I do
not see how other nodes could cause that to happen when they are not
touching the device at all.

 - Pat