Brett Worth wrote:
My original problem is still there however. I've tested the flock functionality of OCFS2 and it works but Xen it seems doesn't do locking even on a shared filesystem. It is possible that Xen is trying to do some other sort of file locking but unfortunately OCFS2 only supports flock.
OCFS2 1.4 (recently released) supports clustered flock:
http://oss.oracle.com/pipermail/ocfs2-announce/2008-August/000027.html
I'm not sure how filesystem locking relates to Xen, though. Xen has nothing to do with it. It only supplies the shared writable (w!) block device.