diff --git a/weed-fs/src/pkg/topology/data_node.go b/weed-fs/src/pkg/topology/data_node.go
index 0410df5f6..1df109da6 100644
--- a/weed-fs/src/pkg/topology/data_node.go
+++ b/weed-fs/src/pkg/topology/data_node.go
@@ -45,7 +45,7 @@ func (dn *DataNode) MatchLocation(ip string, port int) bool {
 	return dn.Ip == ip && dn.Port == port
 }
 func (dn *DataNode) Url() string {
-  return dn.Ip + strconv.Itoa(dn.Port)
+  return dn.Ip + ":" + strconv.Itoa(dn.Port)
 }
 
 func (dn *DataNode) ToMap() interface{} {