diff --git a/internal/querycoord/cluster.go b/internal/querycoord/cluster.go
index 44e4c214d6..7d65d67973 100644
--- a/internal/querycoord/cluster.go
+++ b/internal/querycoord/cluster.go
@@ -75,6 +75,9 @@ type Cluster interface {
 	allocateSegmentsToQueryNode(ctx context.Context, reqs []*querypb.LoadSegmentsRequest, wait bool, excludeNodeIDs []int64, includeNodeIDs []int64) error
 	allocateChannelsToQueryNode(ctx context.Context, reqs []*querypb.WatchDmChannelsRequest, wait bool, excludeNodeIDs []int64) error
 
+	assignNodesToReplicas(ctx context.Context, reqs []*querypb.LoadSegmentsRequest, replicaIds []int64) error
+	assignSegmentsToReplica(ctx context.Context, reqs []*querypb.LoadSegmentsRequest, replicaID int64, wait bool) error
+
 	getSessionVersion() int64
 
 	getMetrics(ctx context.Context, in *milvuspb.GetMetricsRequest) []queryNodeGetMetricsResponse
@@ -700,3 +703,13 @@ func (c *queryNodeCluster) allocateSegmentsToQueryNode(ctx context.Context, reqs
 func (c *queryNodeCluster) allocateChannelsToQueryNode(ctx context.Context, reqs []*querypb.WatchDmChannelsRequest, wait bool, excludeNodeIDs []int64) error {
 	return c.channelAllocator(ctx, reqs, c, c.clusterMeta, wait, excludeNodeIDs)
 }
+
+func (c *queryNodeCluster) assignNodesToReplicas(ctx context.Context, reqs []*querypb.LoadSegmentsRequest, replicaIds []int64) error {
+	// todo(yah01)
+	return nil
+}
+
+func (c *queryNodeCluster) assignSegmentsToReplica(ctx context.Context, reqs []*querypb.LoadSegmentsRequest, replicaID int64, wait bool) error {
+	// todo(yah01)
+	return nil
+}
diff --git a/internal/querycoord/meta.go b/internal/querycoord/meta.go
index c6a16ae0a3..94fe5a1b20 100644
--- a/internal/querycoord/meta.go
+++ b/internal/querycoord/meta.go
@@ -90,6 +90,11 @@ type Meta interface {
 	sendSealedSegmentChangeInfos(collectionID UniqueID, queryChannel string, changeInfos *querypb.SealedSegmentsChangeInfo) (*internalpb.MsgPosition, error)
 
 	getWatchedChannelsByNodeID(nodeID int64) *querypb.UnsubscribeChannelInfo
+
+	addReplica(replicaNum int32, collectionID int64, partitionIds []int64) error
+	setReplicaInfo(replicaID int64, info *querypb.ReplicaInfo) error
+	getReplicaByID(replicaID int64) (*querypb.ReplicaInfo, error)
+	getReplicasByNodeID(nodeID int64, collectionID int64) (*querypb.ReplicaInfo, error)
 }
 
 // MetaReplica records the current load information on all querynodes
@@ -114,6 +119,7 @@ type MetaReplica struct {
 
 	segmentsInfo *segmentsInfo
 	//partitionStates map[UniqueID]*querypb.PartitionStates
+	// replicas *ReplicaInfos
 }
 
 func newMeta(ctx context.Context, kv kv.MetaKv, factory msgstream.Factory, idAllocator func() (UniqueID, error)) (Meta, error) {
@@ -138,6 +144,7 @@ func newMeta(ctx context.Context, kv kv.MetaKv, factory msgstream.Factory, idAll
 		queryStreams:      queryMsgStream,
 
 		segmentsInfo: newSegmentsInfo(kv),
+		// replicas:     NewReplicaInfos(),
 	}
 
 	err := m.reloadFromKV()
@@ -1014,6 +1021,52 @@ func (m *MetaReplica) getWatchedChannelsByNodeID(nodeID int64) *querypb.Unsubscr
 	return unsubscribeChannelInfo
 }
 
+func (m *MetaReplica) addReplica(replicaNum int32, collectionID int64, partitionIds []int64) error {
+	// collection, err := meta.getCollectionInfoByID(collectionId)
+	// if err != nil {
+	// 	return err
+	// }
+
+	// replicas := make([]*querypb.ReplicaInfo, 0, replicaNum)
+
+	// for i := 0; i < int(replicaNum); i++ {
+	// 	replicaId, err := meta.idAllocator()
+	// 	if err != nil {
+	// 		return err
+	// 	}
+
+	// 	replicas = append(replicas, &querypb.ReplicaInfo{
+	// 		ReplicaId:     replicaId,
+	// 		CollectionId:  collectionId,
+	// 		PartitionIds:  partitionIds,
+	// 		ShardReplicas: make([]*querypb.ShardReplica, 0),
+	// 	})
+	// }
+
+	// for _, replica := range replicas {
+	// 	meta.replicas.Insert(replica.ReplicaId, replica)
+	// }
+
+	return nil
+	// todo(yah01)
+}
+
+func (m *MetaReplica) setReplicaInfo(replicaID int64, info *querypb.ReplicaInfo) error {
+	return nil
+	// todo(yah01)
+}
+
+func (m *MetaReplica) getReplicaByID(replicaID int64) (*querypb.ReplicaInfo, error) {
+	return nil, nil
+	// todo(yah01)
+	// return meta.replicas.Get(replicaID)
+}
+
+func (m *MetaReplica) getReplicasByNodeID(nodeID int64, collectionID int64) (*querypb.ReplicaInfo, error) {
+	return nil, nil
+	// todo(yah01)
+}
+
 //func (m *MetaReplica) printMeta() {
 //	m.RLock()
 //	defer m.RUnlock()