Hi friends, Currently I know one way to monitor DNS server - monitor bind by tcp port that has only two state - up or down. But is there any way to check where is DNS is not only listen on some port, but able to resolve queries? I know that check_http can check if page accessible for http server and it should be like that, but for DNS server. So there two general question: 1. Is there built-in function for such task or maybe there somewere exist ready to use plugin/script? 2. If above is not True! What is general rules for writing addon script? What data I should get and procsess and what data I should return? How this data should be formatted (general rules), how I should proccess different events and cases, what return code for each of case and so on... 3. Can somebody give me general advices about how I should accomplish above task? Thanks for any advices!