View source for drupal error "The provided host name is not valid for this server"

drupal version: 8
error message(browser): The provided host name is not valid for this server

problem description: and apache2 web alias using only the site domain name will not pull up the site. The afore mentioned error is presented in the browser.

solution

 $settings['trusted_host_patterns'] = [
  '^localhost$',
  '^www\.mydomain\.com$',
  ''''^mydomain\.com$','''
  '^127\.0\.0\.1$',
];