Cluster /Cluster:yourclustername log /gen /copy "C:\temp"
http://blogs.technet.com/b/pfe-ireland/archive/2008/07/04/windows-2008-clustering-the-cluster-log.aspx
http://blogs.technet.com/b/pfe-ireland/archive/2008/07/04/windows-2008-clustering-the-cluster-log.aspx