No ANY records found for 171.21.3.
Try 21.3 instead?
id 56435, opcode QUERY, rcode NOTIMP, flags QR RD RA ;QUESTION 171.21.3. IN ANY ;ANSWER ;AUTHORITY ;ADDITIONAL
whatsmydns.net ANY Record Lookup tool lets you query DNS servers and get instant results.
Looking for easier to understand results? Use the Global DNS Checker tool.