We endeavor to provide highest possible availability also for this free to use services. However the service is provided on a voluntary basis and there is no guaranteed reachability for particular servers. Thus we recommend using at least two servers.
Our server are located in datacenters with good network connectivity to ensure low latency and least possible packet loss.
Our DNS servers are resolving all queries on their own without relying on other provider-owned servers that might alter result.
DNSSEC is supported and enabled on all our DNS servers to protect against DNS spoofing.