[{"data":1,"prerenderedAt":41},["ShallowReactive",2],{"$f31e6w7nupanoy":3},{"title":4,"seoTitle":5,"description":6,"route":7,"kind":8,"toolKey":9,"intro":10,"indexable":11,"sections":12,"related":38},"CNAME Lookup","CNAME Lookup | nslookup.online","Inspect DNS aliases, follow a bounded CNAME chain, detect loops and review endpoint A and AAAA responses from the chosen resolver.","\u002Fcname-lookup\u002F","tool","cname","Follow an alias and understand where its DNS chain ends.",true,[13,20,26,32],{"id":14,"title":15,"paragraphs":16,"code":19},"read-answer","An alias points to another DNS name",[17,18],"Enter the hostname you want to investigate, including its subdomain. The CNAME owner is an alias and the value is another DNS name. A CNAME is not an IP address and does not redirect a web browser to a different URL.","This tool follows up to ten alias hops and records each query through the selected public recursive resolver. The ten-hop limit is a product safety boundary, not a DNS protocol limit.","www.example.com.  300 IN CNAME edge.example.net.\nedge.example.net. 300 IN A     192.0.2.10\n\nDOCUMENTATION EXAMPLE — not a live DNS response",{"id":21,"title":22,"paragraphs":23},"endpoint","Interpreting the endpoint",[24,25],"Once a name has no returned CNAME, the tool queries A and AAAA records for that endpoint. No address record does not by itself make the original CNAME invalid: a name can be used for something other than a web endpoint.","Some recursive responses already include several aliases. The tool follows the record attached to the current owner, keeps evidence and does not assume the first unrelated CNAME is the next hop.",{"id":27,"title":28,"paragraphs":29},"errors","Loops and incomplete chains",[30,31],"If a name appears twice in the traversal, the tool reports a loop and stops. If a timeout, DNS error or product hop limit interrupts the chain, the result is incomplete rather than a claim that the terminal name is invalid.","A result from a public resolver is not a direct query to every authoritative server. Inspect the source and timestamp when comparing alias observations.",{"id":33,"title":34,"paragraphs":35},"questions","CNAME versus a website redirect",[36,37],"DNS helps find the endpoint for a hostname. Redirects such as HTTP 301 or 302 are sent by a web server after a connection is made. Use a CNAME for DNS aliasing only when it fits the DNS provider’s rules.","A zone apex usually needs SOA and NS data, so a normal CNAME at that same owner is problematic. Provider features named ALIAS or flattening may behave differently and do not necessarily appear as public CNAME records.",[39,40],"\u002Fguides\u002Fa-record-vs-cname\u002F","\u002F",1792661399016]