protected function customizeConfigFiles() {
    /** @var \Acquia\Blt\Robo\Config\BltConfig $config */
    $config = clone $this->getConfig();

    $config->set('drupalvm.config.dir', $this->vmConfigDir);
    $config->expandFileProperties($this->projectDrupalVmVagrantfile);

    // Generate a Random IP address for the new VM.
    $random_local_ip = "192.168." . rand(3, 254) . '.' . rand(3, 254);
    $config->set('random.ip', $random_local_ip);

    $this->setBaseBox($config);

    $config->expandFileProperties($this->projectDrupalVmConfigFile);
  }