[WSO2][ESB][Cluster] Task Scheduling Error

Environment:  ESB 4.9.0
                        Java: 1.8.0
                        Clustered Environment (2 worker nodes with a manager node)
                        Added inbound endpoints for JMS transport

Preconditions: All nodes in cluster should be down

Situation: Start manager node. Can be seen following error.
                 When start worker nodes also can be seen the error.

Error:

 [2016-06-21 06:11:17,741] ERROR - NTaskTaskManager Scheduling task [[NTask::-1234::JMSListener3-JMS--SYNAPSE_INBOUND_ENDPOINT]::JMS--SYNAPSE_INBOUND_ENDPOINT] FAILED. Error: No available task nodes for resolving a task location  
 org.wso2.carbon.ntask.common.TaskException: No available task nodes for resolving a task location  
   at org.wso2.carbon.ntask.core.impl.clustered.ClusteredTaskManager.getTaskLocation(ClusteredTaskManager.java:232)  
   at org.wso2.carbon.ntask.core.impl.clustered.ClusteredTaskManager.locateMemberForTask(ClusteredTaskManager.java:209)  
   at org.wso2.carbon.ntask.core.impl.clustered.ClusteredTaskManager.getMemberIdFromTaskName(ClusteredTaskManager.java:283)  
   at org.wso2.carbon.ntask.core.impl.clustered.ClusteredTaskManager.scheduleTask(ClusteredTaskManager.java:91)  
   at org.wso2.carbon.mediation.ntask.NTaskTaskManager.schedule(NTaskTaskManager.java:103)  
   at org.wso2.carbon.mediation.ntask.NTaskTaskManager.init(NTaskTaskManager.java:350)  
   at org.wso2.carbon.mediation.ntask.NTaskTaskManager.update(NTaskTaskManager.java:363)  
   at org.wso2.carbon.mediation.ntask.internal.NtaskService.updateAndCleanupObservers(NtaskService.java:103)  
   at org.wso2.carbon.mediation.ntask.internal.NtaskService.setConfigurationContextService(NtaskService.java:96)  
   at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)  
   at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)  
   at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)  
   at java.lang.reflect.Method.invoke(Method.java:497)  

Solution:  Start worker nodes in worker profile as follows;

sh wso2server.sh -DworkerNode=true

When you are starting manager node, it may pop up the same error. Because worker nodes are not up yet. After worker nodes are active, you should not get the similar error again.

Relevant issue reported in StackOverflow: http://stackoverflow.com/questions/38051732/wso2-esb-cluster-environment-task-sheduling/