"auth users" is set then the client will be challenged to supply a
username and password to connect to the module. A challenge response
authentication protocol is used for this exchange. The plain text
-usernames are passwords are stored in the file specified by the
+usernames and passwords are stored in the file specified by the
"secrets file" option. The default is for all users to be able to
connect without a password (this is called "anonymous rsync").