diff --git a/dbproxy/mongo/sessionmgr.go b/dbproxy/mongo/sessionmgr.go
index 1e0b34e..d61efa7 100644
--- a/dbproxy/mongo/sessionmgr.go
+++ b/dbproxy/mongo/sessionmgr.go
@@ -143,8 +143,10 @@ func newMgoSession(user, password, host string, port int32, options string) (s *
 	// [mongodb://][user:pass@]host1[:port1][,host2[:port2],...][/database][?options]
 	url := fmt.Sprintf("mongodb://%s%s:%d/admin%s", login, host, port, options)
 	//fmt.Println(url)
+	logger.Logger.Tracef("newMgoSession url:%s", url)
 	session, err := mgo.Dial(url)
 	if err != nil {
+		logger.Logger.Errorf("newMgoSession err:%v", err)
 		return nil, err
 	}
 	session.SetSafe(&mgo.Safe{})