From 8a3cdd21fe904c31f81f8fd53555677b8c7f5cea Mon Sep 17 00:00:00 2001
From: Nikita Koksharov <nkoksharov@redisson.pro>
Date: Thu, 9 Feb 2023 13:34:05 +0300
Subject: [PATCH] Feature - monitorIPChanges setting added for replicated
 servers mode. #4830

---
 .../config/ReplicatedServersConfig.java       | 20 +++++++++++++++++++
 .../ReplicatedConnectionManager.java          |  9 +++++++--
 2 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/redisson/src/main/java/org/redisson/config/ReplicatedServersConfig.java b/redisson/src/main/java/org/redisson/config/ReplicatedServersConfig.java
index 83c7d03cc..4c098161a 100644
--- a/redisson/src/main/java/org/redisson/config/ReplicatedServersConfig.java
+++ b/redisson/src/main/java/org/redisson/config/ReplicatedServersConfig.java
@@ -43,6 +43,8 @@ public class ReplicatedServersConfig extends BaseMasterSlaveServersConfig<Replic
      */
     private int database = 0;
 
+    private boolean monitorIPChanges = false;
+
     public ReplicatedServersConfig() {
     }
 
@@ -51,6 +53,7 @@ public class ReplicatedServersConfig extends BaseMasterSlaveServersConfig<Replic
         setNodeAddresses(config.getNodeAddresses());
         setScanInterval(config.getScanInterval());
         setDatabase(config.getDatabase());
+        setMonitorIPChanges(config.isMonitorIPChanges());
     }
 
     /**
@@ -102,4 +105,21 @@ public class ReplicatedServersConfig extends BaseMasterSlaveServersConfig<Replic
         return database;
     }
 
+    /**
+     * Check each Redis hostname defined in configuration for
+     * IP address changes during scan process.
+     * <p>
+     * Default is <code>false</code>
+     *
+     * @param monitorIPChanges boolean value
+     * @return config
+     */
+    public ReplicatedServersConfig setMonitorIPChanges(boolean monitorIPChanges) {
+        this.monitorIPChanges = monitorIPChanges;
+        return this;
+    }
+
+    public boolean isMonitorIPChanges() {
+        return monitorIPChanges;
+    }
 }
diff --git a/redisson/src/main/java/org/redisson/connection/ReplicatedConnectionManager.java b/redisson/src/main/java/org/redisson/connection/ReplicatedConnectionManager.java
index e5936494e..e4538a3e3 100644
--- a/redisson/src/main/java/org/redisson/connection/ReplicatedConnectionManager.java
+++ b/redisson/src/main/java/org/redisson/connection/ReplicatedConnectionManager.java
@@ -166,14 +166,19 @@ public class ReplicatedConnectionManager extends MasterSlaveConnectionManager {
     private void checkNode(AsyncCountDownLatch latch, RedisURI uri, ReplicatedServersConfig cfg, Set<InetSocketAddress> slaveIPs) {
         CompletionStage<RedisConnection> connectionFuture = connectToNode(cfg, uri, uri.getHost());
         connectionFuture
-                .thenCompose(c -> resolveIP(uri))
+                .thenCompose(c -> {
+                    if (cfg.isMonitorIPChanges()) {
+                        return resolveIP(uri);
+                    }
+                    return CompletableFuture.completedFuture(uri);
+                })
                 .thenCompose(ip -> {
                     if (isShuttingDown()) {
                         return CompletableFuture.completedFuture(null);
                     }
 
                     RedisConnection connection = connectionFuture.toCompletableFuture().join();
-                    if (!ip.equals(connection.getRedisClient().getAddr())) {
+                    if (cfg.isMonitorIPChanges() && !ip.equals(connection.getRedisClient().getAddr())) {
                         disconnectNode(uri);
                         log.info("Hostname: {} has changed IP from: {} to {}", uri, connection.getRedisClient().getAddr(), ip);
                         return CompletableFuture.<Map<String, String>>completedFuture(null);