Nette\Caching\Storages\MemcachedStorage::addServer PHP Method

    public function addServer($host = 'localhost', $port = 11211, $timeout = 1)
    {
        if ($this->memcache->addServer($host, $port, TRUE, 1, $timeout) === FALSE) {
            $error = error_get_last();
            throw new Nette\InvalidStateException("Memcache::addServer(): {$error['message']}.");
        }
    }