code: public function setNetboot($domain, $bootId)
      {
          if (!$domain)
              throw new BadMethodCallException('Parameter $domain is missing.');
          $domain = (string)$domain;
          if (!$bootId)
              throw new BadMethodCallException('Parameter $bootId is missing.');
          $bootId = intval($bootId);
          $payload = array('bootId' => $bootId);
          try {
              $r = $this->put('dedicated/server/' . $domain, array('Content-Type' => 'application/json;charset=UTF-8'), json_encode($payload))->send();
          } catch (\Exception $e) {
              throw new ServerException($e->getMessage(), $e->getCode(), $e);
          }
          return $r->getBody(true);
      }
docs: Set netboot
  
  @param string $domain
  @param int $bootId
  @return \Guzzle\Http\EntityBodyInterface|string
  @throws Exception\ServerException
  @throws \Ovh\Common\Exception\BadMethodCallException