code: func IsDNSZero(dns *cnitypes.DNS) bool {
  	return len(dns.Nameservers) == 0 &&
  		len(dns.Domain) == 0 &&
  		len(dns.Search) == 0 &&
  		len(dns.Options) == 0
  }
docs: /*
   * TODO(cdc) move this to cnitypes
   */
  // IsDNSZero checks if the DNS configuration has any information