diff --git a/weed/server/master_grpc_server.go b/weed/server/master_grpc_server.go
index 34962c83c..bd28a15c8 100644
--- a/weed/server/master_grpc_server.go
+++ b/weed/server/master_grpc_server.go
@@ -87,7 +87,9 @@ func (ms *MasterServer) SendHeartbeat(stream master_pb.Seaweed_SendHeartbeatServ
 			}
 			// update master internal volume layouts
 			t.IncrementalSyncDataNodeRegistration(heartbeat.NewVolumes, heartbeat.DeletedVolumes, dn)
-		} else if len(heartbeat.Volumes) > 0 {
+		}
+
+		if len(heartbeat.Volumes) > 0 {
 			// process heartbeat.Volumes
 			newVolumes, deletedVolumes := t.SyncDataNodeRegistration(heartbeat.Volumes, dn)
 
@@ -99,7 +101,9 @@ func (ms *MasterServer) SendHeartbeat(stream master_pb.Seaweed_SendHeartbeatServ
 				glog.V(0).Infof("master see deleted volume %d from %s", uint32(v.Id), dn.Url())
 				message.DeletedVids = append(message.DeletedVids, uint32(v.Id))
 			}
-		} else if len(heartbeat.EcShards) > 0 {
+		}
+
+		if len(heartbeat.EcShards) > 0 {
 			glog.V(0).Infof("master recieved ec shards from %s: %+v", dn.Url(), heartbeat.EcShards)
 		}
 
diff --git a/weed/storage/erasure_coding/ec_volume_info.go b/weed/storage/erasure_coding/ec_volume_info.go
index 2378ff4e9..9cebb7d40 100644
--- a/weed/storage/erasure_coding/ec_volume_info.go
+++ b/weed/storage/erasure_coding/ec_volume_info.go
@@ -12,6 +12,13 @@ type EcVolumeInfo struct {
 	shardIds   uint16 // use bits to indicate the shard id
 }
 
+func NewEcVolumeInfo(collection string, vid needle.VolumeId) *EcVolumeInfo {
+	return &EcVolumeInfo{
+		Collection: collection,
+		VolumeId:   vid,
+	}
+}
+
 func (ecInfo *EcVolumeInfo) AddShardId(id ShardId) {
 	ecInfo.shardIds |= (1 << id)
 }
diff --git a/weed/topology/data_node.go b/weed/topology/data_node.go
index ff160e178..dba323518 100644
--- a/weed/topology/data_node.go
+++ b/weed/topology/data_node.go
@@ -21,7 +21,7 @@ type DataNode struct {
 	Port         int
 	PublicUrl    string
 	LastSeen     int64 // unix time in seconds
-	ecShards     map[needle.VolumeId]erasure_coding.EcVolumeInfo
+	ecShards     map[needle.VolumeId]*erasure_coding.EcVolumeInfo
 	ecShardsLock sync.RWMutex
 }
 
@@ -30,7 +30,7 @@ func NewDataNode(id string) *DataNode {
 	s.id = NodeId(id)
 	s.nodeType = "DataNode"
 	s.volumes = make(map[needle.VolumeId]storage.VolumeInfo)
-	s.ecShards = make(map[needle.VolumeId]erasure_coding.EcVolumeInfo)
+	s.ecShards = make(map[needle.VolumeId]*erasure_coding.EcVolumeInfo)
 	s.NodeImpl.value = s
 	return s
 }
diff --git a/weed/topology/data_node_ec.go b/weed/topology/data_node_ec.go
index d1715f557..5206a3b51 100644
--- a/weed/topology/data_node_ec.go
+++ b/weed/topology/data_node_ec.go
@@ -4,7 +4,7 @@ import (
 	"github.com/chrislusf/seaweedfs/weed/storage/erasure_coding"
 )
 
-func (dn *DataNode) GetEcShards() (ret []erasure_coding.EcVolumeInfo) {
+func (dn *DataNode) GetEcShards() (ret []*erasure_coding.EcVolumeInfo) {
 	dn.RLock()
 	for _, ecVolumeInfo := range dn.ecShards {
 		ret = append(ret, ecVolumeInfo)
@@ -12,3 +12,9 @@ func (dn *DataNode) GetEcShards() (ret []erasure_coding.EcVolumeInfo) {
 	dn.RUnlock()
 	return ret
 }
+
+func (dn *DataNode) UpdateEcShards(actualShards []*erasure_coding.EcVolumeInfo) (newShards, deletedShards []*erasure_coding.EcVolumeInfo) {
+	dn.ecShardsLock.Lock()
+	dn.ecShardsLock.Unlock()
+	return
+}
diff --git a/weed/topology/topology_ec.go b/weed/topology/topology_ec.go
new file mode 100644
index 000000000..5592b9b64
--- /dev/null
+++ b/weed/topology/topology_ec.go
@@ -0,0 +1,43 @@
+package topology
+
+import (
+	"sort"
+
+	"github.com/chrislusf/seaweedfs/weed/glog"
+	"github.com/chrislusf/seaweedfs/weed/pb/master_pb"
+	"github.com/chrislusf/seaweedfs/weed/storage/erasure_coding"
+	"github.com/chrislusf/seaweedfs/weed/storage/needle"
+)
+
+
+func (t *Topology) SyncDataNodeEcShards(shardInfos []*master_pb.VolumeEcShardInformationMessage, dn *DataNode) (newShards, deletedShards []*erasure_coding.EcVolumeInfo) {
+	// convert into in memory struct storage.VolumeInfo
+	var shards []*erasure_coding.EcVolumeInfo
+	sort.Slice(shardInfos, func(i, j int) bool {
+		return shardInfos[i].Id < shardInfos[j].Id
+	})
+	var prevVolumeId uint32
+	var ecVolumeInfo *erasure_coding.EcVolumeInfo
+	for _, shardInfo := range shardInfos {
+		if shardInfo.Id != prevVolumeId {
+			ecVolumeInfo = erasure_coding.NewEcVolumeInfo(shardInfo.Collection, needle.VolumeId(shardInfo.Id))
+			shards = append(shards, ecVolumeInfo)
+		}
+		ecVolumeInfo.AddShardId(erasure_coding.ShardId(shardInfo.EcIndex))
+	}
+	// find out the delta volumes
+	newShards, deletedShards = dn.UpdateEcShards(shards)
+	for _, v := range newShards {
+		t.RegisterEcShards(v, dn)
+	}
+	for _, v := range deletedShards {
+		t.UnRegisterEcShards(v, dn)
+	}
+	return
+}
+
+func (t *Topology) RegisterEcShards(ecShardInfos *erasure_coding.EcVolumeInfo, dn *DataNode) {
+}
+func (t *Topology) UnRegisterEcShards(ecShardInfos *erasure_coding.EcVolumeInfo, dn *DataNode) {
+	glog.Infof("removing ec shard info:%+v", ecShardInfos)
+}