An authoritative answer is when the dns server hosting the primary copy of the dns record responses to your lookup. For instance, the a record contains mail information and other information shown here. Lets try querying an authoritative only dns server with nslookup. Why does nslookup fail for dns records set to a private address.
If a dns server responded for a dns query which doesnt have original file is known as a nonauthoritative answer. Even though the typens query generated by nslookup did not explicitly ask for. However, nslookup also indicates that the answer is nonauthoritative, meaning that this answer came from the cache of some server rather. With nslookup you will eidier receive a nonaudiontative or authoritative answer.
Does not imply that there is an answer to the query. All it means is that the server you queried is not a master server for the domain in question, so the dns server reached out to another server to find the answer to your question. However, nslookup also indicates that the answer is nonauthoritative, meaning that this answer came from the cache of some server rather than from an. Changes the name of the root server used for queries. Meaning the response is from a cached copy from a thirdparty and not from the primary dns server holding the master copy. Notice that it indicates this is a nonauthoritative answer. Or using nslookup, but with only 1 run for 2 queries. On some networks im able to use nslookup to resolve a domain name that is pointed to a private ip address. For troubleshooting purposes, its important to realize that a cached copy may not contain the most uptodate information. Jan 07, 2016 at the command prompt, type the following. Then when i type nslookup and my domain name i get my domain name, and something about a nonauthoritative answer.
If the answer is correct, the problem was a stale cache entry, and your problem is solved. What does the phrase nonauthoritative answer in the nslookup output mean. If neither of these conditions exist, nslookup will not be able to retrieve any. An authoritative answer comes from a nameserver that is considered authoritative for the domain which its returning a. I dont want to see echos like nonauthoritative answer. When i type nslookup and my ip number i get the namei think that my isp gives me on his machine. Non authoritative answers are not necessarily a problem. Dns server that is providing the answer which is the default local dns server along with three mit nameservers. Jul 24, 2000 im running a dns server on a dsl line. I have obviously misconfigured something in dns2, 3, and 4 but i dont know what. How to hide nonauthorative answer while doing nslookup. The last two lines give you the name you requested and its ip address.
To get an authoritative answer, you will need to specify the authoritative name server as part of your request. Isc, the company that maintains bind, states in the bind manual, page 9. Nonauthoritative answer is expected output when the dns server that returned the result to you is not directly the authoritative nameserver. Why cant i get an authoritative answer from a dns server. Selection from dns on windows server 2003, 3rd edition book. If an answer is listed under nonauthoritative answer, the record is cached. Need info about a nslookup nonauthoritative response.
This can be performed with nslookup using the following steps in interactive mode. Even though the typens query generated by nslookup did not. Reading your request, you seem to try to display mx ip adress for a domain but, nslookup first lines report only name and ip address of your configured dns. Jul 25, 2019 nonauthoritative name servers do not contain original source files of domains zone. If i run nslookup directly on my machine, the output is always. Authoritative answer this is the answer that originates from the dns server which has the information about the zone file. Each of these servers is indeed an authoritative dns server for the hosts on the mit campus. Yet, im getting a nonauthoritative answer, implying the a record is cached on my dns server. Nonauthoritative answer simply means the answer is not fetched from the authoritative dns server for the queried domain name. May 08, 2020 next, we look at the authoritative soa information about the domain. If an authoritative answer cannot be found, the names of any additional. Mar 07, 2020 nonauthoritative answer simply means the answer is not fetched from the authoritative dns server for the queried domain name.
No answer for more information, i append output of dig command. Nonauthoritative answer when a nameserver is not in the list for the domain you did a lookup on. As nslookup could run in interactive mode, and so may answer multiple queries, there is a function using 1 fork to nslookup for asking as many queries needed for listing all ip address for one domain. But avoid asking for help, clarification, or responding to other answers. Finally, the answer also includes the ip addresses of the authoritative. Run nslookup to determine the authoritative dns servers for a university in. This one requires that enter the nslookup prompt first, then set our record type, then enter our domain name to return our result as so. Authoritative versus nonauthoritative answers if youve used nslookup before, you might have noticed that it sometimes precedes its answers with the phrase nonauthoritative answer. On the scvmm 2012 computer nslookup displays the correct nonauthoritative answer nslookup. You receive a nonauthoritative answer because, by default, nslookup asks your nameserver to recurse 111 order to resolve your query and because your nameserver is not an authority for the name you are asking it about. Authoritative answer an overview sciencedirect topics.
The dnsmasq people call it rebind protection, and you can see it both in the dnsmasq manual as the. Tutorial on nslookup commandline tool to query dns records. The information in the nslookup output is probably false b. This is to tell you know that the results was provided by a server that is not the authoritative primary source. Post the full output of your nslookup after you set debug. The information in the output was obtained from a server cache c. Nslookup commands to troubleshoot domain name server netstudy. Just as before, the first two lines tell you the name of the dns server providing the answer and its ip address. Dns request timed out for two requests, then returns nonauthoritative answer. So there is nothing wrong in the screenshot, this is as expected. To get the answer for the question why we get nonauthoritative answer on ns lookup like this. However, nslookup also indicates that the answer is nonauthoritative, meaning that this answer came from the cache of some server rather than from an authoritative mit dns server. Run nslookup to obtain the ip address of a web server in asia.
May 19, 2018 any answer retrieved from the cache of any server is deemed nonauthoritative because it did not come from an authoritative server. Click to see full answer likewise, how do you get an authoritative answer in nslookup. What is authoritative and nonauthoritative dns server. Tells the dns name server to query other servers if it doesnt have the information. An authoritative answer comes from a nameserver ns that is considered authoritative for the domain which its returning a record for one of the nameservers in the list for the domain you did a lookup on. You can use this command to see how many a records are. Yet, im getting a nonauthoritative answer, implying the. When querying a dns server, a dns server will first attempt to resolve the request from its cache. Understanding cyber attacks requires an understanding of how networks. Reverse nslookup returns lame nonauthoritative answer. The same for dns3 and dns4 dig and nslookup run on those servers all work fine. Nslookup where ip address of server is the ip address of the server that you queried originally, and query address is the name or ip address you are attempting to resolve. Nonauthoritative dns servers inetdaemons it tutorials.
Finally, the answer also includes the ip addresses of the authoritative dns servers at smith. They have a cache file for the domains that is constructed from all the dns lookups done previously. In the output of nslookup, you will often notice the statement nonauthoritiative answer as illustrative below as part of the lookup result. Nonauthoritative dns responses dns servers cache responses so that if another local user requests the same host or ip address from the local nameserver, the answer will already be in the local nameservers dns. However, nslookup also indicates that the answer is \nonauthoritative, meaning that this answer came from the cache of some server rather than from an authoritative smith dns server. A nonauthoritative answer comes from anywhere else a nameserver not in the list for the domain you did a lookup on. However, nslookup also indicates that the answer is onauthoritative, meaning that this answer came from the cache of some server rather than from an authoritative smith dns server. I believe that you receive a nonauthoritative answer because, by default, nslookup asks your nameserver to recurse in order to resolve your query and because your nameserver is not an authority for the name you are asking it about. Tutorial on nslookup commandline tool to query dns. Dns request timed out for two requests, then returns.
Appends the dns domain names in the dns domain search list to the request until an answer is. Run nslookup to obtain the ip address of a web server spinlab. Check dns records on windows with nslookup rackspace. Run nslookup to determine the authoritative dns servers for a university in asia. I want to run nslookup in a powershell script, assigning the output to a string variable i can parse up. Not only are these useless, but they can actually screw up the response nslookup. An authoritative answer comes from a nameserver that is considered authoritative for the domain which its returning a record for one of the nameservers in the list for the domain you did a lookup on, and a nonauthoritative answer comes from anywhere else a nameserver not in the list for the domain you did a lookup on. Typically, most of the responses to your nslookup queries are going to be non authoritative.
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