define overlay (
) {

  {
    lowerdir   => "${dir}/root/base",
    upperdir   => "${dir}/root/overlays/${name}",
    workdir    => "${dir}/root/workdirs/${name}",
    nfs_export => 'on',
  }

  file_line {
    ensure => present,
    path   => "${dir}/fstab"
    line   => "overlay root/export/${name} 
  }

}