# File lib/simp/cli/config/utils.rb, line 13
    def validate_fqdn fqdn
      # snarfed from:
      #   https://www.safaribooksonline.com/library/view/regular-expressions-cookbook/9781449327453/ch08s15.html
      regex = %r{\A((?=[a-z0-9-]{1,63}\.)(xn--)?[a-z0-9]+(-[a-z0-9]+)*\.)+[a-z]{2,63}\Z}
      ((fqdn =~ regex) ? true : false )
    end