Multicasting and clustering

What is multicasting in clusterring? I am very much confused currently regarding what kind od address i have to give iin multicasting for that specific cluster?
i have cluster here with address 127.0.0.1 and multicast address as 224.0.0.1. So i am getting 2 errors while booting and shutting down as listed below. PLzzz help me in this matter ASAP.
Error at booting:-
Starting Cluster Service ....
<Sep 17, 2001 11:27:46 PM PDT> <Error> <T3Services>
<TimeRepeat trigger scheduled to run at a date in the past : Mon Sep 17 23:26:46 PDT 2001 , trigger will not repeat>
Error while shutting down server :-
Sep 17, 2001 12:13:01 AM PDT myserver Error cluster disconnecting from cluster MyCluster Sep 17, 2001 12:13:01 AM PDT myserver Error Cluster Multicast socket receive error: java.net.SocketException:socket closed
java.net.SocketException: socket closed
at java.net.PlainDatagramSocketImpl.receive(Native Method)
at java.net.DatagramSocket.receive(DatagramSocket.java:392)
at weblogic.cluster.FragmentSocket.receive(FragmentSocket.java:128)
at weblogic.cluster.MulticastManager.execute(MulticastManager.java:290)
at weblogic.kernel.ExecuteThread.execute(ExecuteThread.java:137)
at weblogic.kernel.ExecuteThread.run(ExecuteThread.java:120)
So plzz help me its urgent!!!

What do you mean when you say that your cluster address is
127.0.0.1?

Hi Vivek,
While doing clustering either on ver5.1 or ver 6.x you require two thing
Firstly, Multicast address. Here is little description...
The cluster multicast address sets the multicast address
used by cluster members to communicate with each other.
It must be a well-formed IP address.
Secondly, Cluster Address for each WL Instance, eg., if you want to start 3 cluster server then you require 3 IP Addresses.
When you finish cluster configuration. First you must start Admin Server followed by Cluster Server. But if you are doing clustering on WLS5.1 then you dont need to start Admin Server, 'coz in WLS5 Cluster, there is no concept of Admin Sever.
Hope this will help. If you still face problem please let me know.
Kind Regards
Rashid
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