applications can be deployed concurrently across a network cluster by utilizing a phased approach to deployment . a preparation operation is invoked each node on which an application is to be deployed . the preparation operation can utilize two phases , in which the deployment descriptors for an application are analyzed and in which each node is initialized for deployment . for each node that is successfully initialized , an activation phase is started in which the node is informed that it should prepare for requests on the application . the deployed application is then started on each successful node . for each node on which the preparation operation was unsuccessful , the deployment can be rolled back or attempted again .