To read the file, you can go to the default directory of %systemroot%\cluster\cluster.log. You can change the directory if you wish by updating the Environment Variable for the server in question. Once you locate the file, you can either open the file in any text based utility of your choice or you can view how to use as well as download the Windows Cluster diagnostic tool at the following URL's:

Cluster Diagnostic Usage -
http://technet.microsoft.com/en-us/library/aa996161(EXCHG.65).aspx

Download Link -
http://www.microsoft.com/downloads/details.aspx?FamilyID=b898f587-88c3-4602-84de-b9bc63f02825&displaylang=en