Michael Wood wrote: > Andre Brinkmann <[EMAIL PROTECTED]> wrote: > >> 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: >> > [snip] > >> Is it possible too change the uuid and other relevant >> parameters? >> > > On Thu, Jul 20, 2006 at 09:29:29AM -0700, Alexei_Roudnev replied: > >> 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. >> > > I am sure he means that he is using something like an HP EVA or > IBM DS4000 etc. that can do a snapshot of a LUN. This looks > like a block for block copy of the original LUN, so if you try > to mount it, the UUIDs etc. will be identical and OCFS2 will > complain. > > i.e. the snapshot "software" is built into the Storage array and > does not need to be aware of any clustering. It just copies (or > copies on write) the data to another area of disk which can be > made available to the original machine(s) or to other machines > entirely. > > In my case, I am using the built-in disks of my cluster, export them via iscsi-target software and couple them via open-iscsi and our own storage virtualization and snapshot software. For OCFS2 (running on the same nodes), there is no distinction between our storage implementation and an HP EVA or IBM DS4000.
Therefore your description hits the critical point. Whatever external snapshot solution is used with OCFS2, you need to be able to change the uuid to use the snapshot and the original volume in the same cluster. Based on the remarks of Joel, I am currently looking inside tunefs.ocfs and think that I will have the feature implemented this evening for evaluation purposes. -- ------------------------------------- Dr.-Ing. André Brinkmann Heinz Nixdorf Institute University of Paderborn Fürstenallee 11 33102 Paderborn Germany ------------------------------------- Email: [EMAIL PROTECTED] Phone: +49-5251-60 63 42 Fax: +49-5251-60 63 51 ------------------------------------- _______________________________________________ Ocfs2-users mailing list Ocfs2-users@oss.oracle.com http://oss.oracle.com/mailman/listinfo/ocfs2-users
