When you have completed cluster configuration and created your file system, you may mount it as any other file system:

mount -t ocfs2 /dev/drbd0 /shared

Your kernel log (accessible by issuing the command dmesg) should then contain a line similar to this one:

ocfs2: Mounting device (147,0) on (node 0, slot 0) with ordered data mode.

From that point forward, you should be able to simultaneously mount your OCFS2 filesystem on both your nodes, in read/write mode.