You would specify a DNS address, a query host name, and an expected response. Based on your input our servers will try to query the specified host name from the provided DNS server and compare the response to the expected response.
If response matches the host will be marked as online otherwise it will be marked as offline.
Please, let us know your thoughts and suggestions by replying to this thread. We value the opinion of our clients, and appreciate all sort of input which can improve the quality and diversity of our services.