diff --git a/modules/elasticsearch/src/main/java/org/elasticsearch/cluster/service/InternalClusterService.java b/modules/elasticsearch/src/main/java/org/elasticsearch/cluster/service/InternalClusterService.java
index 16bcb84d4ed..8938d42757c 100644
--- a/modules/elasticsearch/src/main/java/org/elasticsearch/cluster/service/InternalClusterService.java
+++ b/modules/elasticsearch/src/main/java/org/elasticsearch/cluster/service/InternalClusterService.java
@@ -212,87 +212,95 @@ public class InternalClusterService extends AbstractLifecycleComponent<ClusterSe
                     return;
                 }
                 if (previousClusterState != clusterState) {
-                    if (clusterState.nodes().localNodeMaster()) {
-                        // only the master controls the version numbers
-                        Builder builder = ClusterState.builder().state(clusterState).version(clusterState.version() + 1);
-                        if (previousClusterState.routingTable() != clusterState.routingTable()) {
-                            builder.routingTable(RoutingTable.builder().routingTable(clusterState.routingTable()).version(clusterState.routingTable().version() + 1));
+                    try {
+                        if (clusterState.nodes().localNodeMaster()) {
+                            // only the master controls the version numbers
+                            Builder builder = ClusterState.builder().state(clusterState).version(clusterState.version() + 1);
+                            if (previousClusterState.routingTable() != clusterState.routingTable()) {
+                                builder.routingTable(RoutingTable.builder().routingTable(clusterState.routingTable()).version(clusterState.routingTable().version() + 1));
+                            }
+                            if (previousClusterState.metaData() != clusterState.metaData()) {
+                                builder.metaData(MetaData.builder().metaData(clusterState.metaData()).version(clusterState.metaData().version() + 1));
+                            }
+                            clusterState = builder.build();
+                        } else {
+                            // we got this cluster state from the master, filter out based on versions (don't call listeners)
+                            if (clusterState.version() < previousClusterState.version()) {
+                                logger.debug("got old cluster state [" + clusterState.version() + "<" + previousClusterState.version() + "] from source [" + source + "], ignoring");
+                                return;
+                            }
                         }
-                        if (previousClusterState.metaData() != clusterState.metaData()) {
-                            builder.metaData(MetaData.builder().metaData(clusterState.metaData()).version(clusterState.metaData().version() + 1));
-                        }
-                        clusterState = builder.build();
-                    } else {
-                        // we got this cluster state from the master, filter out based on versions (don't call listeners)
-                        if (clusterState.version() < previousClusterState.version()) {
-                            logger.debug("got old cluster state [" + clusterState.version() + "<" + previousClusterState.version() + "] from source [" + source + "], ignoring");
-                            return;
-                        }
-                    }
 
-                    if (logger.isTraceEnabled()) {
-                        StringBuilder sb = new StringBuilder("cluster state updated:\nversion [").append(clusterState.version()).append("], source [").append(source).append("]\n");
+                        if (logger.isTraceEnabled()) {
+                            StringBuilder sb = new StringBuilder("cluster state updated:\nversion [").append(clusterState.version()).append("], source [").append(source).append("]\n");
+                            sb.append(clusterState.nodes().prettyPrint());
+                            sb.append(clusterState.routingTable().prettyPrint());
+                            sb.append(clusterState.readOnlyRoutingNodes().prettyPrint());
+                            logger.trace(sb.toString());
+                        } else if (logger.isDebugEnabled()) {
+                            logger.debug("cluster state updated, version [{}], source [{}]", clusterState.version(), source);
+                        }
+
+                        ClusterChangedEvent clusterChangedEvent = new ClusterChangedEvent(source, clusterState, previousClusterState);
+                        // new cluster state, notify all listeners
+                        final DiscoveryNodes.Delta nodesDelta = clusterChangedEvent.nodesDelta();
+                        if (nodesDelta.hasChanges() && logger.isInfoEnabled()) {
+                            String summary = nodesDelta.shortSummary();
+                            if (summary.length() > 0) {
+                                logger.info("{}, reason: {}", summary, source);
+                            }
+                        }
+
+                        // TODO, do this in parallel (and wait)
+                        for (DiscoveryNode node : nodesDelta.addedNodes()) {
+                            if (!nodeRequiresConnection(node)) {
+                                continue;
+                            }
+                            try {
+                                transportService.connectToNode(node);
+                            } catch (Exception e) {
+                                // the fault detection will detect it as failed as well
+                                logger.warn("failed to connect to node [" + node + "]", e);
+                            }
+                        }
+
+                        for (ClusterStateListener listener : priorityClusterStateListeners) {
+                            listener.clusterChanged(clusterChangedEvent);
+                        }
+                        for (ClusterStateListener listener : clusterStateListeners) {
+                            listener.clusterChanged(clusterChangedEvent);
+                        }
+                        for (ClusterStateListener listener : lastClusterStateListeners) {
+                            listener.clusterChanged(clusterChangedEvent);
+                        }
+
+                        if (!nodesDelta.removedNodes().isEmpty()) {
+                            threadPool.cached().execute(new Runnable() {
+                                @Override public void run() {
+                                    for (DiscoveryNode node : nodesDelta.removedNodes()) {
+                                        transportService.disconnectFromNode(node);
+                                    }
+                                }
+                            });
+                        }
+
+                        // if we are the master, publish the new state to all nodes
+                        if (clusterState.nodes().localNodeMaster()) {
+                            discoveryService.publish(clusterState);
+                        }
+
+                        if (updateTask instanceof ProcessedClusterStateUpdateTask) {
+                            ((ProcessedClusterStateUpdateTask) updateTask).clusterStateProcessed(clusterState);
+                        }
+
+                        logger.debug("processing [{}]: done applying updated cluster_state", source);
+                    } catch (Exception e) {
+                        StringBuilder sb = new StringBuilder("failed to apply updated cluster state:\nversion [").append(clusterState.version()).append("], source [").append(source).append("]\n");
                         sb.append(clusterState.nodes().prettyPrint());
                         sb.append(clusterState.routingTable().prettyPrint());
                         sb.append(clusterState.readOnlyRoutingNodes().prettyPrint());
-                        logger.trace(sb.toString());
-                    } else if (logger.isDebugEnabled()) {
-                        logger.debug("cluster state updated, version [{}], source [{}]", clusterState.version(), source);
+                        logger.warn(sb.toString(), e);
                     }
-
-                    ClusterChangedEvent clusterChangedEvent = new ClusterChangedEvent(source, clusterState, previousClusterState);
-                    // new cluster state, notify all listeners
-                    final DiscoveryNodes.Delta nodesDelta = clusterChangedEvent.nodesDelta();
-                    if (nodesDelta.hasChanges() && logger.isInfoEnabled()) {
-                        String summary = nodesDelta.shortSummary();
-                        if (summary.length() > 0) {
-                            logger.info("{}, reason: {}", summary, source);
-                        }
-                    }
-
-                    // TODO, do this in parallel (and wait)
-                    for (DiscoveryNode node : nodesDelta.addedNodes()) {
-                        if (!nodeRequiresConnection(node)) {
-                            continue;
-                        }
-                        try {
-                            transportService.connectToNode(node);
-                        } catch (Exception e) {
-                            // the fault detection will detect it as failed as well
-                            logger.warn("failed to connect to node [" + node + "]", e);
-                        }
-                    }
-
-                    for (ClusterStateListener listener : priorityClusterStateListeners) {
-                        listener.clusterChanged(clusterChangedEvent);
-                    }
-                    for (ClusterStateListener listener : clusterStateListeners) {
-                        listener.clusterChanged(clusterChangedEvent);
-                    }
-                    for (ClusterStateListener listener : lastClusterStateListeners) {
-                        listener.clusterChanged(clusterChangedEvent);
-                    }
-
-                    if (!nodesDelta.removedNodes().isEmpty()) {
-                        threadPool.cached().execute(new Runnable() {
-                            @Override public void run() {
-                                for (DiscoveryNode node : nodesDelta.removedNodes()) {
-                                    transportService.disconnectFromNode(node);
-                                }
-                            }
-                        });
-                    }
-
-                    // if we are the master, publish the new state to all nodes
-                    if (clusterState.nodes().localNodeMaster()) {
-                        discoveryService.publish(clusterState);
-                    }
-
-                    if (updateTask instanceof ProcessedClusterStateUpdateTask) {
-                        ((ProcessedClusterStateUpdateTask) updateTask).clusterStateProcessed(clusterState);
-                    }
-
-                    logger.debug("processing [{}]: done applying updated cluster_state", source);
                 } else {
                     logger.debug("processing [{}]: no change in cluster_state", source);
                 }