[Ocfs2-users] Query regarding OCFS2 and RHEL4 LVM

[Joel Becker]

On Mon, Jul 07, 2008 at 05:45:30PM +0530, Vinayak Malap wrote:
> Hi,
>   How can I configure LVM in linux(RHEL4 u5 x86_64) to use with OCFS2 file
> system ?
>   Is there any special configuration steps we need to follow ?
>   Is there any document to guide on this ?

	This belongs on the ocfs2-users at oss.oracle.com mailing list.
The short answer is that LVM is not cluster-safe, so you would have to
create an LVM configuration that makes no changes online.  What do I
mean?  A RAID-5 setup modifies data outside the block being written, and
so is not cluster safe.  A setup that swaps in a hot-spare device is not
safe.  About the only thing that could work is a concatenation of disks,
and you cannot change it while ocfs2 is mounted.
	You can try the clutsered LVM (CLVM), but that uses a different
cluster technology than ocfs2 does, and as such the two cluster stacks
may conflict when a node goes down.
	There are plans to make ocfs2 better work with CLVM in the
future.

Joel

-- 

Life's Little Instruction Book #407

	"Every once in a while, take the scenic route."

Joel Becker
Principal Software Developer
Oracle
E-mail: joel.becker at oracle.com
Phone: (650) 506-8127