cluster logging improvement

redisson/src/main/java/org/redisson/cluster/ClusterConnectionManager.java

@@ -382,12 +382,12 @@ public class ClusterConnectionManager extends MasterSlaveConnectionManager {
 
                     AtomicReference<Throwable> lastException = new AtomicReference<>(ex);
                     if (ex != null) {
-                        checkClusterState(cfg, Collections.emptyIterator(), lastException);
+                        checkClusterState(cfg, Collections.emptyIterator(), lastException, nodes);
                         return;
                     }
 
                     Iterator<RedisURI> nodesIterator = nodes.iterator();
-                    checkClusterState(cfg, nodesIterator, lastException);
+                    checkClusterState(cfg, nodesIterator, lastException, nodes);
                 });
             } else {
                 AtomicReference<Throwable> lastException = new AtomicReference<>();
@@ -411,15 +411,15 @@ public class ClusterConnectionManager extends MasterSlaveConnectionManager {
 
                 Iterator<RedisURI> nodesIterator = nodes.iterator();
 
-                checkClusterState(cfg, nodesIterator, lastException);
+                checkClusterState(cfg, nodesIterator, lastException, nodes);
             }
         }, cfg.getScanInterval(), TimeUnit.MILLISECONDS);
     }
 
-    private void checkClusterState(ClusterServersConfig cfg, Iterator<RedisURI> iterator, AtomicReference<Throwable> lastException) {
+    private void checkClusterState(ClusterServersConfig cfg, Iterator<RedisURI> iterator, AtomicReference<Throwable> lastException, List<RedisURI> allNodes) {
         if (!iterator.hasNext()) {
             if (lastException.get() != null) {
-                log.error("Can't update cluster state", lastException.get());
+                log.error("Can't update cluster state using nodes: {}", allNodes, lastException.getAndSet(null));
             }
             scheduleClusterChangeCheck(cfg);
             return;
@@ -431,29 +431,33 @@ public class ClusterConnectionManager extends MasterSlaveConnectionManager {
         CompletionStage<RedisConnection> connectionFuture = connectToNode(cfg, uri, configEndpointHostName);
         connectionFuture.whenComplete((connection, e) -> {
             if (e != null) {
-                lastException.set(e);
-                checkClusterState(cfg, iterator, lastException);
+                if (!lastException.compareAndSet(null, e)) {
+                    lastException.get().addSuppressed(e);
+                }
+                checkClusterState(cfg, iterator, lastException, allNodes);
                 return;
             }
 
-            updateClusterState(cfg, connection, iterator, uri, lastException);
+            updateClusterState(cfg, connection, iterator, uri, lastException, allNodes);
         });
     }
 
     private void updateClusterState(ClusterServersConfig cfg, RedisConnection connection,
-            Iterator<RedisURI> iterator, RedisURI uri, AtomicReference<Throwable> lastException) {
+            Iterator<RedisURI> iterator, RedisURI uri, AtomicReference<Throwable> lastException, List<RedisURI> allNodes) {
         RFuture<List<ClusterNodeInfo>> future = connection.async(clusterNodesCommand);
         future.whenComplete((nodes, e) -> {
                 if (e != null) {
                     log.error("Unable to execute {}", clusterNodesCommand, e);
-                    lastException.set(e);
-                    checkClusterState(cfg, iterator, lastException);
+                    if (!lastException.compareAndSet(null, e)) {
+                        lastException.get().addSuppressed(e);
+                    }
+                    checkClusterState(cfg, iterator, lastException, allNodes);
                     return;
                 }
 
                 if (nodes.isEmpty()) {
                     log.debug("cluster nodes state got from {}: doesn't contain any nodes", connection.getRedisClient().getAddr());
-                    checkClusterState(cfg, iterator, lastException);
+                    checkClusterState(cfg, iterator, lastException, allNodes);
                     return;
                 }
 
@@ -476,8 +480,11 @@ public class ClusterConnectionManager extends MasterSlaveConnectionManager {
                                     nodesValue.append(clusterNodeInfo.getNodeInfo()).append("\n");
                                 }
                                 log.error("Unable to parse cluster nodes state got from: {}:\n{}", connection.getRedisClient().getAddr(), nodesValue, ex);
-                                lastException.set(ex);
-                                checkClusterState(cfg, iterator, lastException);
+
+                                if (!lastException.compareAndSet(null, ex)) {
+                                    lastException.get().addSuppressed(ex);
+                                }
+                                checkClusterState(cfg, iterator, lastException, allNodes);
                             }
                         })
                         .thenCompose(newPartitions -> checkMasterNodesChange(cfg, newPartitions))