The two mechanism of the server that it uses to find out the unavailability of the server, in the same way it uses the same mechanism to find out the new added server in the cluster. The web-logic server broadcasts a message to all the servers that are available and the servers in return respond to the message to show their availability to the server. If any new server is added then it also sends a message, a check is made to check the list of all the available server instances and if there is no result found then the server is made available in the list. There always remain stubs that monitor the cluster periodically and update the list of available server instances.