Nodes with duplicate Ids are allowed to join cluster.
**Description:**
When two nodes have same node-id , they are still allowed to join the cluster with a warn log.
diff --git a/components/org.wso2.micro.integrator.coordination/src/main/java/org/wso2/micro/integrator/coordination/RDBMSCoordinationStrategy.java b/components/org.wso2.micro.integrator.coordination/src/main/java/org/wso2/micro/integrator/coordination/RDBMSCoordinationStrategy.java
index 6119670e3..0c3e54ede 100644
--- a/components/org.wso2.micro.integrator.coordination/src/main/java/org/wso2/micro/integrator/coordination/RDBMSCoordinationStrategy.java
+++ b/components/org.wso2.micro.integrator.coordination/src/main/java/org/wso2/micro/integrator/coordination/RDBMSCoordinationStrategy.java
@@ -230,10 +230,8 @@ public class RDBMSCoordinationStrategy implements CoordinationStrategy {
                     }
 
                     if (isNodeExist) {
-                        log.warn("Node with ID " + localNodeId + " in group " + localGroupId +
-                                 " already exists.");
-                        stillCoordinator = communicationBusContext.
-                                   updateCoordinatorHeartbeat(localNodeId, localGroupId, System.currentTimeMillis());
+                        throw new ClusterCoordinationException(
+                                "Node with ID " + localNodeId + " in group " + localGroupId + " already exists.");
 
                     }
                     isCoordinatorTasksRunning = true;
['components/org.wso2.micro.integrator.coordination/src/main/java/org/wso2/micro/integrator/coordination/RDBMSCoordinationStrategy.java']