6 Replies Latest reply on Jul 10, 2011 5:49 AM by Muhammad Irfan Masood

    Nodes do not form a cluster

    Muhammad Irfan Masood Newbie



      We have two JBoss instances in a cluster. The instances do not discover each other. We executed the test given under link http://community.jboss.org/wiki/TestingJBoss.This test fails, the cluster view do not show up both nodes. The muticast is enabled on both instances, this is checked by the tests described under http://docs.jboss.org/jbossas/docs/Clustering_Guide/beta422/html/ch07s07s11.html . Please help what can be wrong. Where to debug now?


      Best Regards!



        • 1. Nodes do not form a cluster
          Wolf-Dieter Fink Master


          could you give a bit more information?

          What OS dou you use?

          what version of JBoss do you use?

          both JBoss on one system or two different systems?

          do you use IP binding (option -b for run.sh)?

          With which IP address your instances are started?


          BTW to test the JGroups functionality it is recommend to use the same multicast address and the same ip binding as you try with JBoss, any other combination might have different behaviour.

          See http://community.jboss.org/wiki/TestingJBoss

          • 2. Nodes do not form a cluster
            Muhammad Irfan Masood Newbie

            OS is Windows 2008 server

            JBoss 3.2.5 and JDK 1.4.2

            we are using windows service using wrapper to run the jboss as a windows service

            JBoss instances are running on two seperate servers on  same VLAN

            i am not using farm deployment. the application .ear files is deployed in server/all/deploy folder as exploded archive


            please note currently both nodes are working as  master nodes without forming master and child nodes.


            i dont use ip binding

            below is the configruation being for both nodes.


            any idea why clustering is not being established by both nodes, though mutli casting is working.


            <attribute name="PartitionConfig">


            - <Config>


             UDP: if you have a multihomed machine,
                         set the bind_addr attribute to the appropriate NIC IP address
            --> <!--
             UDP: On Windows machines, because of the media sense feature
                         being broken with multicast (even after disabling media sense)
                         set the loopback attribute to true

            <UDP mcast_addr="" mcast_port="45566" ip_ttl="32" ip_mcast="true" mcast_send_buf_size="800000" mcast_recv_buf_size="150000" ucast_send_buf_size="800000" ucast_recv_buf_size="150000" loopback="false" />


            <PING timeout="2000" num_initial_members="3" up_thread="true" down_thread="true" />


            <MERGE2 min_interval="10000" max_interval="20000" />


            <FD shun="true" up_thread="true" down_thread="true" timeout="2500" max_tries="5" />


            <VERIFY_SUSPECT timeout="3000" num_msgs="3" up_thread="true" down_thread="true" />


            <pbcast.NAKACK gc_lag="50" retransmit_timeout="300,600,1200,2400,4800" max_xmit_size="8192" up_thread="true" down_thread="true" />


            <UNICAST timeout="300,600,1200,2400,4800" window_size="100" min_threshold="10" down_thread="true" />


            <pbcast.STABLE desired_avg_gossip="20000" up_thread="true" down_thread="true" />


            <FRAG frag_size="8192" down_thread="true" up_thread="true" />


            <pbcast.GMS join_timeout="5000" join_retry_timeout="2000" shun="true" print_local_addr="true" />


            <pbcast.STATE_TRANSFER up_thread="true" down_thread="true" />



            • 3. Nodes do not form a cluster
              Wolf-Dieter Fink Master

              Ok, quite old JBoss. but nevertheles it should work.

              It may help to start JBoss for test without using the windows server mode.


              Also I see in your post a hint for windows about setting loopback attribute to TRUE, but you've set it to false.

              What IP addresses your windows server use? different subnet can cause problems.


              Maybe a test with an actual jboss4.3 or the JGroups test with this version (see my previous comment) will help.

              • 4. Nodes do not form a cluster
                Muhammad Irfan Masood Newbie

                Dear Wolf,


                The strange behaviour is that we set up clustering about a two months ago and it worked 100%. After a month we applied small patch which required to restart JBoss. When we restarted one node then it did not joined cluster and when we stopped both and restarted they still not joined cluster. When we started both instances at the same time instantly, both became master nodes, each node has a cluster view having himself as a single node. We noticesd that the machine has two network interfaces, can this cause problems.


                Thanks for your help!


                Best Regards!

                • 5. Nodes do not form a cluster
                  Wolf-Dieter Fink Master

                  The two network interfaces might cause this. It might happen that the missconfiguration is done without effect and you see it only when you restart the instances.


                  It depends on the IP where you bind your JBoss instances and the multicast address.

                  It might be that you can form a cluster with different IP binding and or multicast-address.


                  A simple way to test is http://community.jboss.org/wiki/TestingJBoss

                  You can use it in parallel to the productive JBoss without sideeffect.

                  Here you can check different IP binding and multicast addresses (use only a different mcast port)

                  • 6. Re: Nodes do not form a cluster
                    Muhammad Irfan Masood Newbie

                    This proved to be a network issue, where the switches were upgraded and multicasting was not enabled by default.