NSLOOKUP(1)	    UNIX Programmer's Manual	      NSLOOKUP(1)



NAME
     nslookup - query name servers interactively

SYNOPSIS
     nslookup [ _h_o_s_t-_t_o-_f_i_n_d | - [ _s_e_r_v_e_r _a_d_d_r_e_s_s | _s_e_r_v_e_r _n_a_m_e
     ]]

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


ARGUMENTS
     Interactive mode is entered in the following cases:

     a)  when no arguments are given (the default name server
	 will be used), and

     b)  when the first argument is a hyphen (-) and the second
	 argument is the host name of a name server.

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


INTERACTIVE COMMANDS
     Commands may be interrupted at any time by typing a
     control-C.  To exit, type a control-D (EOF).  The command
     line length must be less than 80 characters.  N.B. an
     unrecognized command will be interpreted as a host name.


     host [server]
	  Look up information for _h_o_s_t using the current default
	  server or using _s_e_r_v_e_r if it is specified.


     server _d_o_m_a_i_n
     lserver _d_o_m_a_i_n
	  Change the default server to _d_o_m_a_i_n. Lserver uses the
	  initial server to look up information about _d_o_m_a_i_n
	  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.





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NSLOOKUP(1)	    UNIX Programmer's Manual	      NSLOOKUP(1)



     root Changes the default server to the server for the root
	  of the domain name space.  Currently, the host sri-
	  nic.arpa is used.  (This command is a synonym for the
	  lserver sri-nic.arpa.) The name of the root server can
	  be changed with the set root command.


     finger [_n_a_m_e] [> _f_i_l_e_n_a_m_e]
     finger [_n_a_m_e] [>> _f_i_l_e_n_a_m_e]
	  Connects with the finger server on the current host.
	  The current host is defined when a previous lookup for
	  a host was successful and returned address information
	  (see the set querytype=A command).  _N_a_m_e is optional. >
	  and >> can be used to redirect output in the usual
	  manner.


     ls _d_o_m_a_i_n [> _f_i_l_e_n_a_m_e]
     ls _d_o_m_a_i_n [>> _f_i_l_e_n_a_m_e]
     ls -a _d_o_m_a_i_n [> _f_i_l_e_n_a_m_e]
     ls -a _d_o_m_a_i_n [>> _f_i_l_e_n_a_m_e]
     ls -h _d_o_m_a_i_n [> _f_i_l_e_n_a_m_e]
     ls -h _d_o_m_a_i_n [>> _f_i_l_e_n_a_m_e]

     ls -d _d_o_m_a_i_n [> _f_i_l_e_n_a_m_e]
	  List the information available for _d_o_m_a_i_n. The default
	  output contains host names and their Internet
	  addresses. The -a option lists aliases of hosts in the
	  domain.  The -h option lists CPU and operating system
	  information for the domain.  The -d option lists all
	  contents of a zone transfer.	When output is directed
	  to a file, hash marks are printed for every 50 records
	  received from the server.


     view _f_i_l_e_n_a_m_e
	  Sorts and lists the output of previous ls command(s)
	  with _m_o_r_e(1).


     help

     ?	  Prints a brief summary of commands.


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

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



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	  [no]debug
	       Turn debugging mode on. A lot more information is
	       printed about the packet sent to the server and
	       the resulting answer.
	       (Default = nodebug, abbreviation = [no]deb)

	  [no]d2
	       Turn exhaustive debugging mode on.  Essentially
	       all fields of every packet are printed.
	       (Default = nod2)

	  [no]defname
	       Append the default domain name to every lookup.
	       (Default = defname, abbreviation = [no]def)

	  [no]search
	       With defname, search for each name in parent
	       domains of the current domain.
	       (Default = search)

	  domain=_n_a_m_e
	       Change the default domain name to _n_a_m_e. The
	       default domain name is appended to all lookup
	       requests if the defname option has been set.  The
	       search list is set to parents of the domain with
	       at least two components in their names.
	       (Default = value in hostname or /etc/resolv.conf,
	       abbreviation = do)

	  querytype=_v_a_l_u_e

	  type=_v_a_l_u_e
	       Change the type of information returned from a
	       query to one of:

	       A	 the host's Internet address (the
			 default).

	       CNAME	 the canonical name for an alias.

	       HINFO	 the host CPU and operating system type.

	       MD	 the mail destination.

	       MX	 the mail exchanger.

	       MG	 the mail group member.

	       MINFO	 the mailbox or mail list information.

	       MR	 the mail rename domain name.




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	       NS	 nameserver for the named zone.
	  Other types specified in the RFC883 document are valid
	  but aren't very useful.
	  (Abbreviation = q)

	  [no]recurse
	       Tell the name server to query other servers if it
	       does not have the information.
	       (Default = recurse, abbreviation = [no]rec)

	  retry=_n_u_m_b_e_r
	       Set the number of retries to _n_u_m_b_e_r. When a reply
	       to a request is not received within a certain
	       amount of time (changed with set timeout), the
	       request is resent. The retry value controls how
	       many times a request is resent before giving up.
	       (Default = 2, abbreviation = ret)

	  root=_h_o_s_t
	       Change the name of the root server to _h_o_s_t. This
	       affects the root command.
	       (Default = sri-nic.arpa, abbreviation = ro)

	  timeout=_n_u_m_b_e_r
	       Change the time-out interval for waiting for a
	       reply to _n_u_m_b_e_r seconds.
	       (Default = 10 seconds, abbreviation = t)

	  [no]vc
	       Always use a virtual circuit when sending requests
	       to the server.
	       (Default = novc, abbreviation = [no]v)

DIAGNOSTICS
     If the lookup request was not successful, an error message
     is printed.  Possible errors are:

     Time-out
	  The server did not respond to a request after a certain
	  amount of time (changed with set timeout=_v_a_l_u_e) and a
	  certain number of retries (changed with set
	  retry=_v_a_l_u_e).

     No information
	  Depending on the query type set with the set querytype
	  command, no information about the host was available,
	  though the host name is valid.

     Non-existent domain
	  The host or domain name does not exist.

     Connection refused



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     Network is unreachable
	  The connection to the name or finger server could not
	  be made at the current time.	This error commonly
	  occurs with finger requests.

     Server failure
	  The name server found an internal inconsistency in its
	  database and could not return a valid answer.

     Refused
	  The name server refused to service the request.


     The following error should not occur and it indicates a bug
     in the program.

     Format error
	  The name server found that the request packet was not
	  in the proper format.


FILES
     /etc/resolv.conf	 initial domain name and name server
     addresses.

SEE ALSO
     resolver(3), resolver(5), named(8), RFC882, RFC883

AUTHOR
     Andrew Cherenson

























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