diff --git a/controller/cluster.go b/controller/cluster.go
index 4f44953..2b975d2 100644
--- a/controller/cluster.go
+++ b/controller/cluster.go
@@ -266,12 +266,18 @@ func (c *ClusterChecker) probeLoop() {
 	}
 }
 
-func (c *ClusterChecker) tryUpdateMigrationStatus(ctx context.Context, cluster *store.Cluster) {
+func (c *ClusterChecker) updateCluster(cluster *store.Cluster) {
+	c.clusterMu.Lock()
+	c.cluster = cluster
+	c.clusterMu.Unlock()
+}
+
+func (c *ClusterChecker) tryUpdateMigrationStatus(ctx context.Context, clonedCluster *store.Cluster) {
 	log := logger.Get().With(
 		zap.String("namespace", c.namespace),
 		zap.String("cluster", c.clusterName))
 
-	for i, shard := range cluster.Shards {
+	for i, shard := range clonedCluster.Shards {
 		if !shard.IsMigrating() {
 			continue
 		}
@@ -283,38 +289,41 @@ func (c *ClusterChecker) tryUpdateMigrationStatus(ctx context.Context, cluster *
 		}
 		if sourceNodeClusterInfo.MigratingSlot != shard.MigratingSlot {
 			log.Error("Mismatch migrate slot", zap.Int("slot", shard.MigratingSlot))
+			return
 		}
-		if shard.TargetShardIndex < 0 || shard.TargetShardIndex >= len(cluster.Shards) {
+		if shard.TargetShardIndex < 0 || shard.TargetShardIndex >= len(clonedCluster.Shards) {
 			log.Error("Invalid target shard index", zap.Int("index", shard.TargetShardIndex))
+			return
 		}
-		targetMasterNode := cluster.Shards[shard.TargetShardIndex].GetMasterNode()
+		targetMasterNode := clonedCluster.Shards[shard.TargetShardIndex].GetMasterNode()
 
 		switch sourceNodeClusterInfo.MigratingState {
 		case "none", "start":
 			continue
 		case "fail":
-			c.clusterMu.Lock()
-			cluster.Shards[i].ClearMigrateState()
-			c.clusterMu.Unlock()
-			if err := c.clusterStore.SetCluster(ctx, c.namespace, cluster); err != nil {
-				log.Error("Failed to clear the migrate state", zap.Error(err))
+			clonedCluster.Shards[i].ClearMigrateState()
+			if err := c.clusterStore.UpdateCluster(ctx, c.namespace, clonedCluster); err != nil {
+				log.Error("Failed to update the cluster", zap.Error(err))
+				return
 			}
+			c.updateCluster(clonedCluster)
 			log.Warn("Failed to migrate the slot", zap.Int("slot", shard.MigratingSlot))
 		case "success":
-			err := cluster.SetSlot(ctx, shard.MigratingSlot, targetMasterNode.ID())
+			err := clonedCluster.SetSlot(ctx, shard.MigratingSlot, targetMasterNode.ID())
 			if err != nil {
 				log.Error("Failed to set the slot", zap.Error(err))
 				return
 			}
-			cluster.Shards[i].SlotRanges = store.RemoveSlotFromSlotRanges(cluster.Shards[i].SlotRanges, shard.MigratingSlot)
-			cluster.Shards[shard.TargetShardIndex].SlotRanges = store.AddSlotToSlotRanges(
-				cluster.Shards[shard.TargetShardIndex].SlotRanges, shard.MigratingSlot)
-			cluster.Shards[i].ClearMigrateState()
-			if err := c.clusterStore.UpdateCluster(ctx, c.namespace, cluster); err != nil {
+			clonedCluster.Shards[i].SlotRanges = store.RemoveSlotFromSlotRanges(clonedCluster.Shards[i].SlotRanges, shard.MigratingSlot)
+			clonedCluster.Shards[shard.TargetShardIndex].SlotRanges = store.AddSlotToSlotRanges(
+				clonedCluster.Shards[shard.TargetShardIndex].SlotRanges, shard.MigratingSlot)
+			clonedCluster.Shards[i].ClearMigrateState()
+			if err := c.clusterStore.UpdateCluster(ctx, c.namespace, clonedCluster); err != nil {
 				log.Error("Failed to update the cluster", zap.Error(err))
 			} else {
 				log.Info("Migrate the slot successfully", zap.Int("slot", shard.MigratingSlot))
 			}
+			c.updateCluster(clonedCluster)
 		default:
 			log.Error("Unknown migrating state", zap.String("state", sourceNodeClusterInfo.MigratingState))
 		}
@@ -332,12 +341,12 @@ func (c *ClusterChecker) migrationLoop() {
 			return
 		case <-ticker.C:
 			c.clusterMu.Lock()
-			cluster := c.cluster
+			clonedCluster := c.cluster.Clone()
 			c.clusterMu.Unlock()
-			if cluster == nil {
+			if clonedCluster == nil {
 				continue
 			}
-			c.tryUpdateMigrationStatus(c.ctx, cluster)
+			c.tryUpdateMigrationStatus(c.ctx, clonedCluster)
 		}
 	}
 }
diff --git a/store/cluster.go b/store/cluster.go
index d4beb06..d4713dd 100644
--- a/store/cluster.go
+++ b/store/cluster.go
@@ -77,6 +77,18 @@ func NewCluster(name string, nodes []string, replicas int) (*Cluster, error) {
 	return cluster, nil
 }
 
+func (cluster *Cluster) Clone() *Cluster {
+	clone := &Cluster{
+		Name:   cluster.Name,
+		Shards: make([]*Shard, 0),
+	}
+	clone.Version.Store(cluster.Version.Load())
+	for _, shard := range cluster.Shards {
+		clone.Shards = append(clone.Shards, shard.Clone())
+	}
+	return clone
+}
+
 // SetPassword will set the password for all nodes in the cluster.
 func (cluster *Cluster) SetPassword(password string) {
 	for i := 0; i < len(cluster.Shards); i++ {
diff --git a/store/cluster_shard.go b/store/cluster_shard.go
index e15333b..1de4dc5 100644
--- a/store/cluster_shard.go
+++ b/store/cluster_shard.go
@@ -66,6 +66,17 @@ func NewShard() *Shard {
 	}
 }
 
+func (shard *Shard) Clone() *Shard {
+	clone := NewShard()
+	clone.SlotRanges = make([]SlotRange, len(shard.SlotRanges))
+	copy(clone.SlotRanges, shard.SlotRanges)
+	clone.TargetShardIndex = shard.TargetShardIndex
+	clone.MigratingSlot = shard.MigratingSlot
+	clone.Nodes = make([]Node, len(shard.Nodes))
+	copy(clone.Nodes, shard.Nodes)
+	return clone
+}
+
 func (shard *Shard) ClearMigrateState() {
 	shard.MigratingSlot = -1
 	shard.TargetShardIndex = -1