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1st chunk of `nslookup.man`
4930d5e016d5d772725e39268e06ce1b6c6b3b36cd8b2f2a0000000100000e65
NSLOOKUP(1)                          BIND 9                         NSLOOKUP(1)

NAME
       nslookup - query Internet name servers interactively

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

DESCRIPTION
       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
       prints just the name and requested information for a host or domain.

ARGUMENTS
       Interactive mode is entered in the following cases:

       a. when no arguments are given (the default name server is used);

       b. 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 de‐
       fault query type to host information, with an initial timeout of 10 sec‐
       onds, type:

          nslookup -query=hinfo  -timeout=10

       The -version option causes nslookup to print the version number and  im‐
       mediately exit.

INTERACTIVE COMMANDS
       host [server]
              This  command looks up information for host using the current de‐
              fault server or using server, if specified. If host is an  Inter‐
              net  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  pe‐
              riod (.), 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
              These commands 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  an‐
              swer  cannot  be  found, the names of servers that might have the
              answer are returned.

       root   This command is not implemented.

       finger This command is not implemented.

       ls     This command is not implemented.

       view   This command is not implemented.

       help   This command is not implemented.

       ?      This command is not implemented.

       exit   This command exits the program.

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

              all    This keyword prints the current values of  the  frequently
                     used options to set. Information about the current default
                     server and host is also printed.

              class=value
                     This keyword changes the query class to one of:

                     IN     the Internet class

                     CH     the Chaos class

                     HS     the Hesiod class

                     ANY    wildcard

                     The class specifies the protocol group of the information.
                     The  default  is  IN; the abbreviation for this keyword is
                     cl.

              nodebug
Title: nslookup: Querying Internet Name Servers
Summary
The `nslookup` command is a tool for querying Internet domain name servers. It has interactive and non-interactive modes. Interactive mode allows users to query name servers for information about hosts and domains, while non-interactive mode simply prints the requested information. The document details the usage, arguments, options, and interactive commands available in `nslookup`, including commands for looking up host information, changing default servers, and setting query options.