A cluster resource is the database and all of its dependencies. A dependency is an additional resource that the database requires to successfully function. Dependencies for the database resource include page writers, the after-image writer, the before-image writer, the physical disks the database resides on, the network, etc. A resource must be a member of the cluster. PROCLUSTER registers resources that need to be persisted in a cluster environment. You must register your database as a resource; however, you do not need to identify any dependencies for the database.