diff --git a/perl-xCAT/xCAT/Utils.pm b/perl-xCAT/xCAT/Utils.pm
index 1528881c5..4bc678c9c 100644
--- a/perl-xCAT/xCAT/Utils.pm
+++ b/perl-xCAT/xCAT/Utils.pm
@@ -2992,10 +2992,12 @@ sub noderangecontainsMn
    }
   }
  }
- if (grep(/$mname/, @noderange)) { # if MN in the noderange
-   return $mname;
- } else {
-   return ;
+ if ($mname) {  # if Management Node defined in the database
+   if (grep(/$mname/, @noderange)) { # if MN in the noderange
+     return $mname;
+    } else {
+     return ;
+   }
  }
 }