[{"data":1,"prerenderedAt":58},["ShallowReactive",2],{"$f2cw6k1theja4i":3},{"title":4,"seoTitle":5,"description":6,"route":7,"kind":8,"toolKey":9,"intro":10,"indexable":11,"sections":12,"related":53},"How to use the nslookup command","How to use the nslookup command | nslookup.online","Practical nslookup examples for A, MX, TXT and PTR queries on Windows and Linux, including resolver selection and error interpretation.","\u002Fguides\u002Fnslookup-command\u002F","guide",null,"Use a terminal to ask a specific resolver a specific DNS question.",true,[13,20,27,34,41,47],{"id":14,"title":15,"paragraphs":16,"code":19},"first-query","Make one explicit query",[17,18],"On Windows, open a terminal and use the built-in nslookup command. On Linux, availability depends on the distribution; it is commonly included in DNS utility packages. Follow your distribution’s normal package guidance rather than running an unfamiliar installer.","A name-only lookup commonly asks for address information using the system’s configured resolver. A public web lookup may use a different recursive resolver, so differing results are not automatically a bug.","nslookup example.com\nnslookup example.com 8.8.8.8",{"id":21,"title":22,"paragraphs":23,"code":26},"record-type","Choose the record type",[24,25],"Use the type option to request mail exchanges, text, nameservers or IPv6 addresses. The owner name matters: _dmarc.example.com is a different question from example.com.","Do not rely on ANY as a complete inventory. Recursive servers can provide minimal ANY responses or refuse them. Ask for the individual types you need, and keep their statuses separate.","nslookup -type=MX example.com\nnslookup -type=TXT _dmarc.example.com\nnslookup -type=AAAA example.com\nnslookup -type=NS example.com",{"id":28,"title":29,"paragraphs":30,"code":33},"reverse","Run a reverse lookup",[31,32],"An IP input asks for its PTR mapping. IPv4 uses a reversed-octet owner below in-addr.arpa; IPv6 uses reversed hexadecimal nibbles below ip6.arpa. The returned hostname is not a list of every website served by the IP.","A missing PTR does not prove a host is offline. Reverse and forward records can be managed by different parties and do not update each other automatically.","nslookup 1.1.1.1\nnslookup -type=PTR 1.1.1.1.in-addr.arpa",{"id":35,"title":36,"paragraphs":37,"code":40},"interactive","Use interactive mode deliberately",[38,39],"Start nslookup without a name to enter its prompt. You can change the type and the resolver for the next query. Exit the prompt when done; these commands query DNS rather than modifying records.","A non-authoritative answer normally means a recursive resolver supplied the response, possibly from cache. It is not an automatic warning that the data is untrustworthy.","nslookup\n> server 1.1.1.1\n> set type=TXT\n> example.com\n> exit",{"id":42,"title":43,"paragraphs":44},"errors","Keep DNS and transport errors separate",[45,46],"NXDOMAIN means the queried name was reported absent; NOERROR with no requested data means something different. SERVFAIL can involve validation, upstream failures or other conditions. A timeout means the request did not complete.","When comparing a command and this website, match the name, type, resolver and query time. This website uses HTTPS; your terminal may use UDP or TCP. The measured durations are not directly comparable.",{"id":48,"title":49,"paragraphs":50},"next","Record what you actually observed",[51,52],"Keep the owner name, type, answer, TTL, resolver and time together. Copying only an IP address can hide that it came from a different hostname or an older cached response.","For a production issue, retain a known-good configuration and use the provider’s authoritative tools where appropriate. Neither a web lookup nor nslookup changes DNS records for you.",[54,55,56,57],"\u002F","\u002Fmx-lookup\u002F","\u002Ftxt-lookup\u002F","\u002Freverse-dns-lookup\u002F",1792661399124]