Fixed - clients duplication during discovering ip change of hostname. #1304

redisson/src/main/java/org/redisson/connection/DNSMonitor.java

@@ -136,7 +136,14 @@ public class DNSMonitor {
                                 log.info("Detected DNS change. Slave {} has changed ip from {} to {}", 
                                         entry.getKey().getHost(), currentSlaveAddr.getAddress().getHostAddress(), newSlaveAddr.getAddress().getHostAddress());
                                 for (final MasterSlaveEntry masterSlaveEntry : connectionManager.getEntrySet()) {
-                                    if (masterSlaveEntry.hasSlave(currentSlaveAddr)) {
+                                    if (!masterSlaveEntry.hasSlave(currentSlaveAddr)) {
+                                        continue;
+                                    }
+                                    
+                                    if (masterSlaveEntry.hasSlave(newSlaveAddr)) {
+                                        masterSlaveEntry.slaveUp(newSlaveAddr, FreezeReason.MANAGER);
+                                        masterSlaveEntry.slaveDown(currentSlaveAddr, FreezeReason.MANAGER);
+                                    } else {
                                         RFuture<Void> addFuture = masterSlaveEntry.addSlave(newSlaveAddr, entry.getKey());
                                         addFuture.addListener(new FutureListener<Void>() {
                                             @Override
@@ -149,8 +156,8 @@ public class DNSMonitor {
                                                 masterSlaveEntry.slaveDown(currentSlaveAddr, FreezeReason.MANAGER);
                                             }
                                         });
-                                        break;
                                     }
+                                    break;
                                 }
                                 slaves.put(entry.getKey(), newSlaveAddr);
                             }

redisson/src/main/java/org/redisson/connection/MasterSlaveEntry.java

@@ -428,7 +428,7 @@ public class MasterSlaveEntry {
         // exclude master from slaves
         if (!config.checkSkipSlavesInit()
                 && !addr.equals(entry.getClient().getAddr())) {
-            slaveDown(masterEntry.getClient().getAddr(), FreezeReason.SYSTEM);
+            slaveDown(addr, FreezeReason.SYSTEM);
             log.info("master {} excluded from slaves", addr);
         }
         return true;
@@ -443,11 +443,27 @@ public class MasterSlaveEntry {
         // exclude master from slaves
         if (!config.checkSkipSlavesInit()
                 && !URIBuilder.compare(addr, address)) {
-            slaveDown(masterEntry.getClient().getAddr(), FreezeReason.SYSTEM);
+            slaveDown(addr, FreezeReason.SYSTEM);
             log.info("master {} excluded from slaves", addr);
         }
         return true;
     }
+    
+    public boolean slaveUp(InetSocketAddress address, FreezeReason freezeReason) {
+        if (!slaveBalancer.unfreeze(address, freezeReason)) {
+            return false;
+        }
+
+        InetSocketAddress addr = masterEntry.getClient().getAddr();
+        // exclude master from slaves
+        if (!config.checkSkipSlavesInit()
+                && !addr.equals(address)) {
+            slaveDown(addr, FreezeReason.SYSTEM);
+            log.info("master {} excluded from slaves", addr);
+        }
+        return true;
+    }
+
 
     /**
      * Freeze slave with <code>redis(s)://host:port</code> from slaves list.