diff --git a/perl-xCAT/xCAT/Usage.pm b/perl-xCAT/xCAT/Usage.pm
index 5d87d8825..fcad48817 100644
--- a/perl-xCAT/xCAT/Usage.pm
+++ b/perl-xCAT/xCAT/Usage.pm
@@ -92,7 +92,7 @@ my %usage = (
        getmacs <noderange> [-V|--verbose]
        getmacs [-h|--help|-v|--version]
    PPC specific:
-       getmacs <noderange> [-d][-S server -G gateway -C client]",
+       getmacs <noderange> [-f][-d][-S server -G gateway -C client]",
     "mkvm" => 
 "Usage: mkvm singlenode -i id -n noderange [-V|--verbose]
        mkvm srccec -c destcec [-V|--verbose]