This bug has been copied from bug #673615 and has been proposed to be backported to 5.6 z-stream (EUS).
Fixed in lvm2-cluster-2.02.74-3.el5_6.1
Marking verified (Sanity Only) as QE was never able to reproduce this issue.
Technical note added. If any revisions are required, please edit the "Technical Notes" field accordingly. All revisions will be proofread by the Engineering Content Services team. New Contents: Under certain circumstances, mainly on shared storage systems, the buffered read of a device was used instead of a direct device access. This could result in the use of outdated metadata values. This update ensures that all device scan operations use the direct device access.
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on therefore solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHBA-2011-0288.html