Because "undef" overrides the parameter defaults in mysql::server, include mysql::params and use the mysql::params::* variables as defaults for the hiera calls. It is ugly but it works as intended.
Because "undef" overrides the parameter defaults in mysql::server,
include mysql::params and use the mysql::params::* variables as
defaults for the hiera calls. It is ugly but it works as intended.

mgruener/puppet-zarafa