diff --git a/weed/shell/command_volume_balance.go b/weed/shell/command_volume_balance.go
index c2c668c90..6dd248844 100644
--- a/weed/shell/command_volume_balance.go
+++ b/weed/shell/command_volume_balance.go
@@ -86,6 +86,7 @@ func (c *commandVolumeBalance) Do(args []string, commandEnv *CommandEnv, writer
 
 	volumeServers := collectVolumeServersByDc(resp.TopologyInfo, *dc)
 	volumeReplicas, _ := collectVolumeReplicaLocations(resp)
+	diskTypes := collectVolumeDiskTypes(resp.TopologyInfo)
 
 	if *collection == "EACH_COLLECTION" {
 		collections, err := ListCollectionNames(commandEnv, true, false)
@@ -93,16 +94,16 @@ func (c *commandVolumeBalance) Do(args []string, commandEnv *CommandEnv, writer
 			return err
 		}
 		for _, c := range collections {
-			if err = balanceVolumeServers(commandEnv, volumeReplicas, volumeServers, resp.VolumeSizeLimitMb*1024*1024, c, *applyBalancing); err != nil {
+			if err = balanceVolumeServers(commandEnv, diskTypes, volumeReplicas, volumeServers, resp.VolumeSizeLimitMb*1024*1024, c, *applyBalancing); err != nil {
 				return err
 			}
 		}
 	} else if *collection == "ALL_COLLECTIONS" {
-		if err = balanceVolumeServers(commandEnv, volumeReplicas, volumeServers, resp.VolumeSizeLimitMb*1024*1024, "ALL_COLLECTIONS", *applyBalancing); err != nil {
+		if err = balanceVolumeServers(commandEnv, diskTypes, volumeReplicas, volumeServers, resp.VolumeSizeLimitMb*1024*1024, "ALL_COLLECTIONS", *applyBalancing); err != nil {
 			return err
 		}
 	} else {
-		if err = balanceVolumeServers(commandEnv, volumeReplicas, volumeServers, resp.VolumeSizeLimitMb*1024*1024, *collection, *applyBalancing); err != nil {
+		if err = balanceVolumeServers(commandEnv, diskTypes, volumeReplicas, volumeServers, resp.VolumeSizeLimitMb*1024*1024, *collection, *applyBalancing); err != nil {
 			return err
 		}
 	}
@@ -110,9 +111,9 @@ func (c *commandVolumeBalance) Do(args []string, commandEnv *CommandEnv, writer
 	return nil
 }
 
-func balanceVolumeServers(commandEnv *CommandEnv, volumeReplicas map[uint32][]*VolumeReplica, nodes []*Node, volumeSizeLimit uint64, collection string, applyBalancing bool) error {
+func balanceVolumeServers(commandEnv *CommandEnv, diskTypes []storage.DiskType, volumeReplicas map[uint32][]*VolumeReplica, nodes []*Node, volumeSizeLimit uint64, collection string, applyBalancing bool) error {
 
-	for _, diskType := range []storage.DiskType{storage.HardDriveType, storage.SsdType} {
+	for _, diskType := range diskTypes {
 		if err := balanceVolumeServersByDiskType(commandEnv, diskType, volumeReplicas, nodes, volumeSizeLimit, collection, applyBalancing); err != nil {
 			return err
 		}
@@ -123,8 +124,7 @@ func balanceVolumeServers(commandEnv *CommandEnv, volumeReplicas map[uint32][]*V
 
 func balanceVolumeServersByDiskType(commandEnv *CommandEnv, diskType storage.DiskType, volumeReplicas map[uint32][]*VolumeReplica, nodes []*Node, volumeSizeLimit uint64, collection string, applyBalancing bool) error {
 
-	// balance writable hdd volumes
-	// fmt.Fprintf(os.Stdout, "\nbalance collection %s writable hdd volumes\n", collection)
+	// balance writable volumes
 	for _, n := range nodes {
 		n.selectVolumes(func(v *master_pb.VolumeInformationMessage) bool {
 			if collection != "ALL_COLLECTIONS" {
@@ -139,8 +139,7 @@ func balanceVolumeServersByDiskType(commandEnv *CommandEnv, diskType storage.Dis
 		return err
 	}
 
-	// balance readable hdd volumes
-	// fmt.Fprintf(os.Stdout, "\nbalance collection %s readable hdd volumes\n", collection)
+	// balance readable volumes
 	for _, n := range nodes {
 		n.selectVolumes(func(v *master_pb.VolumeInformationMessage) bool {
 			if collection != "ALL_COLLECTIONS" {
@@ -176,6 +175,25 @@ func collectVolumeServersByDc(t *master_pb.TopologyInfo, selectedDataCenter stri
 	return
 }
 
+func collectVolumeDiskTypes(t *master_pb.TopologyInfo) (diskTypes []storage.DiskType) {
+	knownTypes := make(map[string]bool)
+	for _, dc := range t.DataCenterInfos {
+		for _, r := range dc.RackInfos {
+			for _, dn := range r.DataNodeInfos {
+				for _, vi := range dn.VolumeInfos {
+					if _, found := knownTypes[vi.DiskType]; !found {
+						knownTypes[vi.DiskType] = true
+					}
+				}
+			}
+		}
+	}
+	for diskType, _ := range knownTypes {
+		diskTypes = append(diskTypes, storage.ToDiskType(diskType))
+	}
+	return
+}
+
 type Node struct {
 	info            *master_pb.DataNodeInfo
 	selectedVolumes map[uint32]*master_pb.VolumeInformationMessage