code: public function serverGetByTSDNS($tsdns)
      {
          $parts = Uri::getFQDNParts($tsdns);
          $query = StringHelper::factory(array_shift($parts));
  
          while ($part = array_shift($parts)) {
              $query->prepend($part);
  
              try {
                  $port = TeamSpeak3::factory("tsdns://" . $query . "/?timeout=3")->resolve($tsdns)->section(":", 1);
  
                  return $this->serverGetByPort($port == "" ? 9987 : $port);
              } catch (Ts3Exception $e) {
                  /* skip "Connection timed out" and "Connection refused" */
                  if ($e->getCode() != 10060 && $e->getCode() != 10061) {
                      throw $e;
                  }
              }
          }
  
          throw new Ts3Exception("invalid serverID", 0x400);
      }
docs: Returns the first Server object matching the given TSDNS hostname. Like the
  TeamSpeak 3 Client, this method will start looking for a TSDNS server on the second-level
  domain including a fallback to the third-level domain of the specified $tsdns parameter.
  
  @param  string $tsdns
  @throws Ts3Exception
  @return Server