diff --git a/weed/server/master_grpc_server_assign.go b/weed/server/master_grpc_server_assign.go
index 5839a6a73..7455c9ea4 100644
--- a/weed/server/master_grpc_server_assign.go
+++ b/weed/server/master_grpc_server_assign.go
@@ -85,7 +85,7 @@ func (ms *MasterServer) Assign(ctx context.Context, req *master_pb.AssignRequest
 				return nil, fmt.Errorf("no free volumes left for " + option.String())
 			}
 			vl.AddGrowRequest()
-			ms.vgCh <- &topology.VolumeGrowRequest{
+			ms.volumeGrowthRequestChan <- &topology.VolumeGrowRequest{
 				Option: option,
 				Count:  int(req.WritableVolumeCount),
 			}
diff --git a/weed/server/master_grpc_server_volume.go b/weed/server/master_grpc_server_volume.go
index a344e5221..503da7fd4 100644
--- a/weed/server/master_grpc_server_volume.go
+++ b/weed/server/master_grpc_server_volume.go
@@ -22,7 +22,7 @@ func (ms *MasterServer) ProcessGrowRequest() {
 	go func() {
 		filter := sync.Map{}
 		for {
-			req, ok := <-ms.vgCh
+			req, ok := <-ms.volumeGrowthRequestChan
 			if !ok {
 				break
 			}
diff --git a/weed/server/master_server.go b/weed/server/master_server.go
index 9a5313a10..a2f3c7692 100644
--- a/weed/server/master_server.go
+++ b/weed/server/master_server.go
@@ -60,8 +60,8 @@ type MasterServer struct {
 	preallocateSize int64
 
 	Topo *topology.Topology
-	vg   *topology.VolumeGrowth
-	vgCh chan *topology.VolumeGrowRequest
+	vg                      *topology.VolumeGrowth
+	volumeGrowthRequestChan chan *topology.VolumeGrowRequest
 
 	boundedLeaderChan chan int
 
@@ -105,14 +105,14 @@ func NewMasterServer(r *mux.Router, option *MasterOption, peers map[string]pb.Se
 
 	grpcDialOption := security.LoadClientTLS(v, "grpc.master")
 	ms := &MasterServer{
-		option:          option,
-		preallocateSize: preallocateSize,
-		vgCh:            make(chan *topology.VolumeGrowRequest, 1<<6),
-		clientChans:     make(map[string]chan *master_pb.KeepConnectedResponse),
-		grpcDialOption:  grpcDialOption,
-		MasterClient:    wdclient.NewMasterClient(grpcDialOption, "", cluster.MasterType, option.Master, "", "", *pb.NewServiceDiscoveryFromMap(peers)),
-		adminLocks:      NewAdminLocks(),
-		Cluster:         cluster.NewCluster(),
+		option:                  option,
+		preallocateSize:         preallocateSize,
+		volumeGrowthRequestChan: make(chan *topology.VolumeGrowRequest, 1<<6),
+		clientChans:             make(map[string]chan *master_pb.KeepConnectedResponse),
+		grpcDialOption:          grpcDialOption,
+		MasterClient:            wdclient.NewMasterClient(grpcDialOption, "", cluster.MasterType, option.Master, "", "", *pb.NewServiceDiscoveryFromMap(peers)),
+		adminLocks:              NewAdminLocks(),
+		Cluster:                 cluster.NewCluster(),
 	}
 	ms.boundedLeaderChan = make(chan int, 16)
 
diff --git a/weed/server/master_server_handlers.go b/weed/server/master_server_handlers.go
index 9dc6351a4..e4188420d 100644
--- a/weed/server/master_server_handlers.go
+++ b/weed/server/master_server_handlers.go
@@ -136,7 +136,7 @@ func (ms *MasterServer) dirAssignHandler(w http.ResponseWriter, r *http.Request)
 				return
 			}
 			vl.AddGrowRequest()
-			ms.vgCh <- &topology.VolumeGrowRequest{
+			ms.volumeGrowthRequestChan <- &topology.VolumeGrowRequest{
 				Option: option,
 				Count:  writableVolumeCount,
 			}