When you deploy an EJB, you specify the server instances and clusters to which the EJB deployment is targeted. After you have deployed an EJB, you can update the server instances and clusters to which it is targeted.
To set target server instances and clusters for a deployed EJB:
By default, the Administration Console deploys an EJB to all server instances in the cluster (the "All servers in the cluster" option). To deploy the EJB to selected servers in a cluster, select "Part of the cluster", and then select the individual server instances to which you want to deploy the EJB.