diff --git a/structure.yml b/structure.yml
index 996b18d..2baca0b 100644
--- a/structure.yml
+++ b/structure.yml
@@ -17,12 +17,12 @@ vps:  # vps target server system variables
     examples:
       - ./sshkeys/myssh_privatekey
     type: unix_filename
-    mandatory: false
     params:
       types:
         - file
       test_existence: true
       allow_relative: true
+    mandatory: false
 
 nginx:
   description: pedagogic html static file server