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Commands and references ( GNU / linux kernel 2.4.18-3 and 2.4.18-14 )   
Linux is a registered trademark of Linus Torvalds

The commands with their most common usage are in brackets like this: [ command ].
Don't type the brackets, just what is inside of them.

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Query internet domain name servers
[ nslookup ]

The command should be followed by an ipaddress or domain name

NSLOOKUP(1)							   NSLOOKUP(1)

       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

       Interactive mode is entered in the following cases:

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

       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 sec-
       ond 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

       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

       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.

		     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)

		     Turn debugging mode on. A lot more information is printed
		     about the packet sent to the  server  and	the  resulting

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

	      [no]d2 Turn debugging mode on. A lot more information is printed
		     about the packet sent to the  server  and	the  resulting

		     (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 top of the information query.

		     (Default = A; abbreviations = q, ty)

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

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

		     Set the number of retries to 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

		     (Default = novc)


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

       Andrew Cherenson

BIND9				 Jun 30, 2000			   NSLOOKUP(1)

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