Novell Messenger does not require the existence of a GroupWise system in the cluster, but presumably one has already been set up as described in Section 2.0, Planning GroupWise in a NetWare Cluster and Section 3.0, Setting Up a Domain and Post Office in a NetWare Cluster. As part of the process of setting up GroupWise in the cluster, you filled out the System Clustering Worksheet. Some of the information from that worksheet is helpful as you implement Messenger in your cluster.