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

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

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)

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

           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)

RETURN VALUES

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

FILES

       /etc/resolv.conf

SEE ALSO

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

AUTHOR

       Internet Systems Consortium, Inc.

COPYRIGHT

       Copyright (C) 2004-2007, 2010, 2013-2017 Internet Systems Consortium, Inc. ("ISC")

ISC                                                                 2014-01-24                                                         NSLOOKUP(1)