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NSLOOKUP(1) 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-inter-
active 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 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
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 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 debugging mode on. A lot more information is
printed about the packet sent to the server and the
resulting answer.
(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 top 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)
FILES
/etc/resolv.conf
SEE ALSO
dig(1), host(1), named(8).
AUTHOR
Andrew Cherenson
BIND9 Jun 30, 2000 NSLOOKUP(1)
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