See a post I made about this a while back, it may help:
https://oss.oracle.com/pipermail/ocfs2-users/2012-March/005686.html
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>
>Message: 1
>Date: Sat, 19 Jan 2013 11:46:47 +0100 (CET)
>From: "Heiko L." <heikol at fh-lausitz.de>
>Subject: [Ocfs2-users] multipath ocfs2 start by-label missing
>To: ocfs2-users at oss.oracle.com
>
>Hallo,
>
>I want to use multipath and ocfs2.
>After run "ocfs2 start" entry under disk/by-label hidden.
>Instead wants ocfs2 connected as "sdb".
>
>Whats going wrong?
>
>regards Heiko