diff --git a/Dockerfile b/Dockerfile
index b2291c15f..e87538fdb 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -7,7 +7,7 @@ RUN echo tlsv1 >> ~/.curlrc
 
 RUN \
   curl -Lks https://bintray.com$(curl -Lk http://bintray.com/chrislusf/seaweedfs/seaweedfs/_latestVersion | grep linux_amd64.tar.gz | sed -n "/href/ s/.*href=['\"]\([^'\"]*\)['\"].*/\1/gp") | gunzip | tar -xf - -C /opt/weed/ && \
-  mkdir ./bin &&  mv weed_*/* ./bin && \
+  mkdir ./bin &&  mv ./*/* ./bin && \
   chmod +x ./bin/weed
 
 EXPOSE 8080
diff --git a/weed/command/export.go b/weed/command/export.go
index 481aa111b..5a7dc71d9 100644
--- a/weed/command/export.go
+++ b/weed/command/export.go
@@ -51,7 +51,7 @@ func init() {
 var (
 	output = cmdExport.Flag.String("o", "", "output tar file name, must ends with .tar, or just a \"-\" for stdout")
 	format = cmdExport.Flag.String("fileNameFormat", defaultFnFormat, "filename formatted with {{.Mime}} {{.Id}} {{.Name}} {{.Ext}}")
-	newer  = cmdExport.Flag.String("newer", "", "export only files newer than this time, default is all files. Must be specified in RFC3339 without timezone")
+	newer  = cmdExport.Flag.String("newer", "", "export only files newer than this time, default is all files. Must be specified in RFC3339 without timezone, e.g. 2006-01-02T15:04:05")
 
 	tarOutputFile          *tar.Writer
 	tarHeader              tar.Header
diff --git a/weed/topology/data_node.go b/weed/topology/data_node.go
index da6ed2895..b7f039559 100644
--- a/weed/topology/data_node.go
+++ b/weed/topology/data_node.go
@@ -53,7 +53,7 @@ func (dn *DataNode) UpdateVolumes(actualVolumes []storage.VolumeInfo) (deletedVo
 	for _, v := range actualVolumes {
 		actualVolumeMap[v.Id] = v
 	}
-	dn.RLock()
+	dn.Lock()
 	for vid, v := range dn.volumes {
 		if _, ok := actualVolumeMap[vid]; !ok {
 			glog.V(0).Infoln("Deleting volume id:", vid)
@@ -62,8 +62,8 @@ func (dn *DataNode) UpdateVolumes(actualVolumes []storage.VolumeInfo) (deletedVo
 			dn.UpAdjustVolumeCountDelta(-1)
 			dn.UpAdjustActiveVolumeCountDelta(-1)
 		}
-	} //TODO: adjust max volume id, if need to reclaim volume ids
-	dn.RUnlock()
+	}
+	dn.Unlock()
 	for _, v := range actualVolumes {
 		dn.AddOrUpdateVolume(v)
 	}