diff --git a/weed/topology/data_center.go b/weed/topology/data_center.go
index 250e4bbdd..60d91ba6d 100644
--- a/weed/topology/data_center.go
+++ b/weed/topology/data_center.go
@@ -44,7 +44,8 @@ func (dc *DataCenter) ToMap() interface{} {
 
 func (dc *DataCenter) ToDataCenterInfo() *master_pb.DataCenterInfo {
 	m := &master_pb.DataCenterInfo{
-		Id:                string(dc.Id()),
+		Id:        string(dc.Id()),
+		DiskInfos: dc.diskUsages.ToDiskInfo(),
 	}
 	for _, c := range dc.Children() {
 		rack := c.(*Rack)
diff --git a/weed/topology/data_node.go b/weed/topology/data_node.go
index 038d87043..ae69534da 100644
--- a/weed/topology/data_node.go
+++ b/weed/topology/data_node.go
@@ -128,6 +128,25 @@ func (dn *DataNode) DeltaUpdateVolumes(newVolumes, deletedVolumes []storage.Volu
 	return
 }
 
+func (dn *DataNode) AdjustMaxVolumeCounts(maxVolumeCounts map[string]uint32) {
+	deltaDiskUsages := newDiskUsages()
+	for diskType, maxVolumeCount := range maxVolumeCounts {
+		if maxVolumeCount == 0 {
+			// the volume server may have set the max to zero
+			continue
+		}
+		dt := types.ToDiskType(diskType)
+		currentDiskUsage := dn.diskUsages.getOrCreateDisk(dt)
+		if currentDiskUsage.maxVolumeCount == int64(maxVolumeCount) {
+			continue
+		}
+		disk := dn.getOrCreateDisk(dt.String())
+		deltaDiskUsage := deltaDiskUsages.getOrCreateDisk(dt)
+		deltaDiskUsage.maxVolumeCount = int64(maxVolumeCount) - currentDiskUsage.maxVolumeCount
+		disk.UpAdjustDiskUsageDelta(deltaDiskUsages)
+	}
+}
+
 func (dn *DataNode) GetVolumes() (ret []storage.VolumeInfo) {
 	dn.RLock()
 	for _, c := range dn.children {
diff --git a/weed/topology/disk.go b/weed/topology/disk.go
index 831528949..0e8ce60cd 100644
--- a/weed/topology/disk.go
+++ b/weed/topology/disk.go
@@ -42,7 +42,7 @@ func newDiskUsages() *DiskUsages {
 	}
 }
 
-func (d *DiskUsages) negative() (*DiskUsages) {
+func (d *DiskUsages) negative() *DiskUsages {
 	d.RLock()
 	defer d.RUnlock()
 	t := newDiskUsages()
@@ -68,6 +68,21 @@ func (d *DiskUsages) ToMap() interface{} {
 	return ret
 }
 
+func (d *DiskUsages) ToDiskInfo() (map[string]*master_pb.DiskInfo) {
+	ret := make(map[string]*master_pb.DiskInfo)
+	for diskType, diskUsageCounts := range d.usages {
+		m := &master_pb.DiskInfo{
+			VolumeCount:       uint64(diskUsageCounts.volumeCount),
+			MaxVolumeCount:    uint64(diskUsageCounts.maxVolumeCount),
+			FreeVolumeCount:   uint64(diskUsageCounts.maxVolumeCount - diskUsageCounts.volumeCount),
+			ActiveVolumeCount: uint64(diskUsageCounts.activeVolumeCount),
+			RemoteVolumeCount: uint64(diskUsageCounts.remoteVolumeCount),
+		}
+		ret[string(diskType)] = m
+	}
+	return ret
+}
+
 func (d *DiskUsages) FreeSpace() (freeSpace int64) {
 	d.RLock()
 	defer d.RUnlock()
@@ -77,7 +92,6 @@ func (d *DiskUsages) FreeSpace() (freeSpace int64) {
 	return
 }
 
-
 func (d *DiskUsages) GetMaxVolumeCount() (maxVolumeCount int64) {
 	d.RLock()
 	defer d.RUnlock()
@@ -111,13 +125,13 @@ func (a *DiskUsageCounts) FreeSpace() int64 {
 	return freeVolumeSlotCount
 }
 
-func (a *DiskUsageCounts) minus(b *DiskUsageCounts) (*DiskUsageCounts) {
+func (a *DiskUsageCounts) minus(b *DiskUsageCounts) *DiskUsageCounts {
 	return &DiskUsageCounts{
-		volumeCount: a.volumeCount - b.volumeCount,
+		volumeCount:       a.volumeCount - b.volumeCount,
 		remoteVolumeCount: a.remoteVolumeCount - b.remoteVolumeCount,
 		activeVolumeCount: a.activeVolumeCount - b.activeVolumeCount,
-		ecShardCount: a.ecShardCount - b.ecShardCount,
-		maxVolumeCount: a.maxVolumeCount - b.maxVolumeCount,
+		ecShardCount:      a.ecShardCount - b.ecShardCount,
+		maxVolumeCount:    a.maxVolumeCount - b.maxVolumeCount,
 	}
 }
 
@@ -248,7 +262,7 @@ func (d *Disk) ToDiskInfo() *master_pb.DiskInfo {
 		Type:              string(d.Id()),
 		VolumeCount:       uint64(diskUsage.volumeCount),
 		MaxVolumeCount:    uint64(diskUsage.maxVolumeCount),
-		FreeVolumeCount:   uint64(d.FreeSpace()),
+		FreeVolumeCount:   uint64(diskUsage.maxVolumeCount - diskUsage.volumeCount),
 		ActiveVolumeCount: uint64(diskUsage.activeVolumeCount),
 		RemoteVolumeCount: uint64(diskUsage.remoteVolumeCount),
 	}
diff --git a/weed/topology/node.go b/weed/topology/node.go
index 1f5e4194c..25b048452 100644
--- a/weed/topology/node.go
+++ b/weed/topology/node.go
@@ -186,22 +186,6 @@ func (n *NodeImpl) ReserveOneVolume(r int64, option *VolumeGrowOption) (assigned
 	return nil, errors.New("No free volume slot found!")
 }
 
-func (n *NodeImpl) AdjustMaxVolumeCounts(maxVolumeCounts map[string]uint32) {
-	deltaDiskUsages := newDiskUsages()
-	for diskType, maxVolumeCount := range maxVolumeCounts {
-		if maxVolumeCount == 0 {
-			// the volume server may have set the max to zero
-			continue
-		}
-		dt := types.ToDiskType(diskType)
-		deltaDiskUsage := deltaDiskUsages.getOrCreateDisk(dt)
-		currentDiskUsage := n.diskUsages.getOrCreateDisk(dt)
-		deltaDiskUsage.maxVolumeCount = int64(maxVolumeCount) - currentDiskUsage.maxVolumeCount
-		deltaDiskUsages.getOrCreateDisk(dt).maxVolumeCount = int64(maxVolumeCount)
-	}
-	n.UpAdjustDiskUsageDelta(deltaDiskUsages)
-}
-
 func (n *NodeImpl) UpAdjustDiskUsageDelta(deltaDiskUsages *DiskUsages) { //can be negative
 	for diskType, diskUsage := range deltaDiskUsages.usages {
 		existingDisk := n.getOrCreateDisk(diskType)
diff --git a/weed/topology/rack.go b/weed/topology/rack.go
index 95fd260ad..8eb2a717c 100644
--- a/weed/topology/rack.go
+++ b/weed/topology/rack.go
@@ -66,7 +66,8 @@ func (r *Rack) ToMap() interface{} {
 
 func (r *Rack) ToRackInfo() *master_pb.RackInfo {
 	m := &master_pb.RackInfo{
-		Id:                string(r.Id()),
+		Id:        string(r.Id()),
+		DiskInfos: r.diskUsages.ToDiskInfo(),
 	}
 	for _, c := range r.Children() {
 		dn := c.(*DataNode)
diff --git a/weed/topology/topology_map.go b/weed/topology/topology_map.go
index aa2c9afcd..0fedb6221 100644
--- a/weed/topology/topology_map.go
+++ b/weed/topology/topology_map.go
@@ -80,7 +80,8 @@ func (t *Topology) ToVolumeLocations() (volumeLocations []*master_pb.VolumeLocat
 
 func (t *Topology) ToTopologyInfo() *master_pb.TopologyInfo {
 	m := &master_pb.TopologyInfo{
-		Id:                string(t.Id()),
+		Id:        string(t.Id()),
+		DiskInfos: t.diskUsages.ToDiskInfo(),
 	}
 	for _, c := range t.Children() {
 		dc := c.(*DataCenter)