man--nslookup

NSLOOKUP(1)                          BIND9                         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 is used to print just the name and requested
       information for a host or domain.

ARGUMENTS
       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

INTERACTIVE COMMANDS
       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.

       root
           not implemented

       finger
           not implemented

       ls
           not implemented

       view
           not implemented

       help
           not implemented

       ?
           not implemented

       exit
           Exits the program.

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

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

               class=value
                   Change 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.

                       (Default = IN; abbreviation = cl)

                [no]debug
                   Turn on or off the display of the full response packet and any
                   intermediate response packets when searching.

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

                [no]d2
                   Turn debugging mode on or off. This displays more about what nslookup is
                   doing.

                   (Default = nod2)

               domain=name
                   Sets the search list to name.

                [no]search
                   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)

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

                   (Default = 53; abbreviation = po)

               querytype=value

               type=value
                   Change the type of the information query.

                   (Default = A; abbreviations = q, ty)

                [no]recurse
                   Tell the name server to query other servers if it does not have the
                   information.

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

               retry=number
                   Set the number of retries to number.

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

                [no]vc
                   Always use a virtual circuit when sending requests to the server.

                   (Default = novc)

                [no]fail
                   Try the next nameserver if a nameserver responds with SERVFAIL or a
                   referral (nofail) or terminate query (fail) on such a response.

                   (Default = nofail)

FILES
       /etc/resolv.conf

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

AUTHOR
       Andrew Cherenson

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

BIND9                            Jun 30, 2000                      NSLOOKUP(1)
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