diff --git a/docs/reference/advanced_configuration.rst b/docs/reference/advanced_configuration.rst
index d1eb89ef8..29e77264e 100644
--- a/docs/reference/advanced_configuration.rst
+++ b/docs/reference/advanced_configuration.rst
@@ -96,7 +96,7 @@ Full configuration options:
                 port: 21
                 passive: false
                 create: false
-                mode: 2 # this is the FTP_BINARY constant. see: http://php.net/manual/en/ftp.constants.php
+                mode: !php/const FTP_BINARY # @see: https://www.php.net/manual/en/ftp.constants.php
 
             s3:
                 bucket: