diff --git a/doc/guides/nics/features/default.ini b/doc/guides/nics/features/default.ini
index 21178e1632..c96a52b58e 100644
--- a/doc/guides/nics/features/default.ini
+++ b/doc/guides/nics/features/default.ini
@@ -86,6 +86,7 @@ ecpri                =
 esp                  =
 eth                  =
 e_tag                =
+flex                 =
 fuzzy                =
 geneve               =
 geneve_opt           =