Provided by: bind9-dnsutils_9.16.1-0ubuntu2_amd64 bug


       nslookup - query Internet name servers interactively


       nslookup [-option] [name | -] [server]


       Nslookup is a program to query Internet domain name servers.  Nslookup has two modes:
       interactive and non-interactive. Interactive mode allows the user to query name servers
       for information about various hosts and domains or to print a list of hosts in a domain.
       Non-interactive mode is used to print just the name and requested information for a host
       or domain.


       Interactive mode is entered in the following cases:

        1. when no arguments are given (the default name server will be used)

        2. when the first argument is a hyphen (-) and the second argument is the host name or
           Internet address of a name server.

       Non-interactive mode is used when the name or Internet address of the host to be looked up
       is given as the first argument. The optional second argument specifies the host name or
       address of a name server.

       Options can also be specified on the command line if they precede the arguments and are
       prefixed with a hyphen. For example, to change the default query type to host information,
       and the initial timeout to 10 seconds, type:

           nslookup -query=hinfo  -timeout=10

       The -version option causes nslookup to print the version number and immediately exits.


       host [server]
           Look up information for host using the current default server or using server, if
           specified. If host is an Internet address and the query type is A or PTR, the name of
           the host is returned. If host is a name and does not have a trailing period, the
           search list is used to qualify the name.

           To look up a host not in the current domain, append a period to the name.

       server domain

       lserver domain
           Change the default server to domain; lserver uses the initial server to look up
           information about domain, while server uses the current default server. If an
           authoritative answer can't be found, the names of servers that might have the answer
           are returned.

           not implemented

           not implemented

           not implemented

           not implemented

           not implemented

           not implemented

           Exits the program.

       set keyword[=value]
           This command is used to change state information that affects the lookups. Valid
           keywords are:

               Prints the current values of the frequently used options to set. Information about
               the current default server and host is also printed.

               Change the query class to one of:

                   the Internet class

                   the Chaos class

                   the Hesiod class


               The class specifies the protocol group of the information.

               (Default = IN; abbreviation = cl)

               Turn on or off the display of the full response packet and any intermediate
               response packets when searching.

               (Default = nodebug; abbreviation = [no]deb)

               Turn debugging mode on or off. This displays more about what nslookup is doing.

               (Default = nod2)

               Sets the search list to name.

               If the lookup request contains at least one period but doesn't end with a trailing
               period, append the domain names in the domain search list to the request until an
               answer is received.

               (Default = search)

               Change the default TCP/UDP name server port to value.

               (Default = 53; abbreviation = po)


               Change the type of the information query.

               (Default = A and then AAAA; abbreviations = q, ty)

               Note: It is only possible to specify one query type, only the default behavior
               looks up both when an alternative is not specified.

               Tell the name server to query other servers if it does not have the information.

               (Default = recurse; abbreviation = [no]rec)

               Set the number of dots (label separators) in a domain that will disable searching.
               Absolute names always stop searching.

               Set the number of retries to number.

               Change the initial timeout interval for waiting for a reply to number seconds.

               Always use a virtual circuit when sending requests to the server.

               (Default = novc)

               Try the next nameserver if a nameserver responds with SERVFAIL or a referral
               (nofail) or terminate query (fail) on such a response.

               (Default = nofail)


       nslookup returns with an exit status of 1 if any query failed, and 0 otherwise.


       If nslookup has been built with IDN (internationalized domain name) support, it can accept
       and display non-ASCII domain names.  nslookup appropriately converts character encoding of
       domain name before sending a request to DNS server or displaying a reply from the server.
       If you'd like to turn off the IDN support for some reason, define the IDN_DISABLE
       environment variable. The IDN support is disabled if the variable is set when nslookup
       runs or when the standard output is not a tty.




       dig(1), host(1), named(8).


       Internet Systems Consortium, Inc.


       Copyright © 2004-2007, 2010, 2013-2020 Internet Systems Consortium, Inc. ("ISC")