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<refentry id="man.dig">

<refentryinfo>

<date>June 30, 2000</date>

</refentryinfo>

<refmeta>

<refentrytitle>dig</refentrytitle>

<manvolnum>1</manvolnum>

<refmiscinfo>BIND9</refmiscinfo>

</refmeta>

<refnamediv>

<refname>dig</refname>

<refpurpose>DNS lookup utility</refpurpose>

</refnamediv>

<docinfo>

<copyright>

<year>2004</year>

<year>2005</year>

<year>2006</year>

<year>2007</year>

<year>2008</year>

<year>2009</year>

<year>2010</year>

<year>2011</year>

<year>2013</year>

<year>2014</year>

<holder>Internet Systems Consortium, Inc. ("ISC")</holder>

</copyright>

<copyright>

<year>2000</year>

<year>2001</year>

<year>2002</year>

<year>2003</year>

<holder>Internet Software Consortium.</holder>

</copyright>

</docinfo>

<refsynopsisdiv>

<cmdsynopsis>

<command>dig</command>

<arg choice="opt">@server</arg>

<arg><option>-b <replaceable class="parameter">address</replaceable></option></arg>

<arg><option>-c <replaceable class="parameter">class</replaceable></option></arg>

<arg><option>-f <replaceable class="parameter">filename</replaceable></option></arg>

<arg><option>-k <replaceable class="parameter">filename</replaceable></option></arg>

<arg><option>-m</option></arg>

<arg><option>-p <replaceable class="parameter">port#</replaceable></option></arg>

<arg><option>-q <replaceable class="parameter">name</replaceable></option></arg>

<arg><option>-t <replaceable class="parameter">type</replaceable></option></arg>

<arg><option>-x <replaceable class="parameter">addr</replaceable></option></arg>

<arg><option>-y <replaceable class="parameter"><optional>hmac:</optional>name:key</replaceable></option></arg>

<arg><option>-4</option></arg>

<arg><option>-6</option></arg>

<arg choice="opt">name</arg>

<arg choice="opt">type</arg>

<arg choice="opt">class</arg>

<arg choice="opt" rep="repeat">queryopt</arg>

</cmdsynopsis>

<cmdsynopsis>

<command>dig</command>

<arg><option>-h</option></arg>

</cmdsynopsis>

<cmdsynopsis>

<command>dig</command>

<arg choice="opt" rep="repeat">global-queryopt</arg>

<arg choice="opt" rep="repeat">query</arg>

</cmdsynopsis>

</refsynopsisdiv>

<refsect1>

<title>DESCRIPTION</title>

<para><command>dig</command>

(domain information groper) is a flexible tool

for interrogating DNS name servers. It performs DNS lookups and

displays the answers that are returned from the name server(s) that

were queried. Most DNS administrators use <command>dig</command> to

troubleshoot DNS problems because of its flexibility, ease of use and

clarity of output. Other lookup tools tend to have less functionality

than <command>dig</command>.

</para>

<para>

Although <command>dig</command> is normally used with

command-line

arguments, it also has a batch mode of operation for reading lookup

requests from a file. A brief summary of its command-line arguments

and options is printed when the <option>-h</option> option is given.

Unlike earlier versions, the BIND 9 implementation of

<command>dig</command> allows multiple lookups to be issued

from the

command line.

</para>

<para>

Unless it is told to query a specific name server,

<command>dig</command> will try each of the servers listed in

<filename>/etc/resolv.conf</filename>. If no usable server addresses

are found, <command>dig</command> will send the query to the local

host.

</para>

<para>

When no command line arguments or options are given,

<command>dig</command> will perform an NS query for "." (the root).

</para>

<para>

It is possible to set per-user defaults for <command>dig</command> via

<filename>${HOME}/.digrc</filename>. This file is read and

any options in it

are applied before the command line arguments.

</para>

<para>

The IN and CH class names overlap with the IN and CH top level

domain names. Either use the <option>-t</option> and

<option>-c</option> options to specify the type and class,

use the <option>-q</option> the specify the domain name, or

use "IN." and "CH." when looking up these top level domains.

</para>

</refsect1>

<refsect1>

<title>SIMPLE USAGE</title>

<para>

A typical invocation of <command>dig</command> looks like:

<programlisting> dig @server name type </programlisting>

where:

<variablelist>

<varlistentry>

<term><constant>server</constant></term>

<listitem>

<para>

is the name or IP address of the name server to query. This

can be an IPv4 address in dotted-decimal notation or an IPv6

address in colon-delimited notation. When the supplied

<parameter>server</parameter> argument is a hostname,

<command>dig</command> resolves that name before querying

that name server.

</para>

<para>

If no <parameter>server</parameter> argument is

provided, <command>dig</command> consults

<filename>/etc/resolv.conf</filename>; if an

address is found there, it queries the name server at

that address. If either of the <option>-4</option> or

<option>-6</option> options are in use, then

only addresses for the corresponding transport

will be tried. If no usable addresses are found,

<command>dig</command> will send the query to the

local host. The reply from the name server that

responds is displayed.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><constant>name</constant></term>

<listitem>

<para>

is the name of the resource record that is to be looked up.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><constant>type</constant></term>

<listitem>

<para>

indicates what type of query is required &mdash;

ANY, A, MX, SIG, etc.

<parameter>type</parameter> can be any valid query

type. If no

<parameter>type</parameter> argument is supplied,

<command>dig</command> will perform a lookup for an

A record.

</para>

</listitem>

</varlistentry>

</variablelist>

</para>

</refsect1>

<refsect1>

<title>OPTIONS</title>

<para>

The <option>-b</option> option sets the source IP address of the query

to <parameter>address</parameter>. This must be a valid

address on

one of the host's network interfaces or "0.0.0.0" or "::". An optional

port

may be specified by appending "#&lt;port&gt;"

</para>

<para>

The default query class (IN for internet) is overridden by the

<option>-c</option> option. <parameter>class</parameter> is

any valid

class, such as HS for Hesiod records or CH for Chaosnet records.

</para>

<para>

The <option>-f</option> option makes <command>dig </command>

operate

in batch mode by reading a list of lookup requests to process from the

file <parameter>filename</parameter>. The file contains a

number of

queries, one per line. Each entry in the file should be organized in

the same way they would be presented as queries to

<command>dig</command> using the command-line interface.

</para>

<para>

The <option>-m</option> option enables memory usage debugging.

<!-- It enables ISC_MEM_DEBUGTRACE and ISC_MEM_DEBUGRECORD

</para>

<para>

If a non-standard port number is to be queried, the

<option>-p</option> option is used. <parameter>port#</parameter> is

the port number that <command>dig</command> will send its

queries

instead of the standard DNS port number 53. This option would be used

to test a name server that has been configured to listen for queries

on a non-standard port number.

</para>

<para>

The <option>-4</option> option forces <command>dig</command>

to only

use IPv4 query transport. The <option>-6</option> option forces

<command>dig</command> to only use IPv6 query transport.

</para>

<para>

The <option>-t</option> option sets the query type to

<parameter>type</parameter>. It can be any valid query type

which is

supported in BIND 9. The default query type is "A", unless the

<option>-x</option> option is supplied to indicate a reverse lookup.

A zone transfer can be requested by specifying a type of AXFR. When

an incremental zone transfer (IXFR) is required,

<parameter>type</parameter> is set to <literal>ixfr=N</literal>.

The incremental zone transfer will contain the changes made to the zone

since the serial number in the zone's SOA record was

<parameter>N</parameter>.

</para>

<para>

The <option>-q</option> option sets the query name to

<parameter>name</parameter>. This is useful to distinguish the

<parameter>name</parameter> from other arguments.

</para>

<para>

Reverse lookups &mdash; mapping addresses to names &mdash; are simplified by the

<option>-x</option> option. <parameter>addr</parameter> is

an IPv4

address in dotted-decimal notation, or a colon-delimited IPv6 address.

When this option is used, there is no need to provide the

<parameter>name</parameter>, <parameter>class</parameter> and

<parameter>type</parameter> arguments. <command>dig</command>

automatically performs a lookup for a name like

<literal>11.12.13.10.in-addr.arpa</literal> and sets the

query type and

class to PTR and IN respectively. By default, IPv6 addresses are

looked up using nibble format under the IP6.ARPA domain.

To use the older RFC1886 method using the IP6.INT domain

specify the <option>-i</option> option. Bit string labels (RFC2874)

are now experimental and are not attempted.

</para>

<para>

To sign the DNS queries sent by <command>dig</command> and

their

responses using transaction signatures (TSIG), specify a TSIG key file

using the <option>-k</option> option. You can also specify the TSIG

key itself on the command line using the <option>-y</option> option;

<parameter>hmac</parameter> is the type of the TSIG, default HMAC-MD5,

<parameter>name</parameter> is the name of the TSIG key and

<parameter>key</parameter> is the actual key. The key is a

base-64

encoded string, typically generated by

<citerefentry>

<refentrytitle>dnssec-keygen</refentrytitle><manvolnum>8</manvolnum>

</citerefentry>.

Caution should be taken when using the <option>-y</option> option on

multi-user systems as the key can be visible in the output from

<citerefentry>

<refentrytitle>ps</refentrytitle><manvolnum>1</manvolnum>

</citerefentry>

or in the shell's history file. When

using TSIG authentication with <command>dig</command>, the name

server that is queried needs to know the key and algorithm that is

being used. In BIND, this is done by providing appropriate

<command>key</command> and <command>server</command> statements in

<filename>named.conf</filename>.

</para>

</refsect1>

<refsect1>

<title>QUERY OPTIONS</title>

<para><command>dig</command>

provides a number of query options which affect

the way in which lookups are made and the results displayed. Some of

these set or reset flag bits in the query header, some determine which

sections of the answer get printed, and others determine the timeout

and retry strategies.

</para>

<para>

Each query option is identified by a keyword preceded by a plus sign

(<literal>+</literal>). Some keywords set or reset an

option. These may be preceded

by the string <literal>no</literal> to negate the meaning of

that keyword. Other

keywords assign values to options like the timeout interval. They

have the form <option>+keyword=value</option>.

The query options are:

<variablelist>

<varlistentry>

<term><option>+[no]tcp</option></term>

<listitem>

<para>

Use [do not use] TCP when querying name servers. The default

behavior is to use UDP unless an AXFR or IXFR query is

requested, in

which case a TCP connection is used.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]vc</option></term>

<listitem>

<para>

Use [do not use] TCP when querying name servers. This alternate

syntax to <parameter>+[no]tcp</parameter> is

provided for backwards

compatibility. The "vc" stands for "virtual circuit".

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]ignore</option></term>

<listitem>

<para>

Ignore truncation in UDP responses instead of retrying with TCP.

By

default, TCP retries are performed.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+domain=somename</option></term>

<listitem>

<para>

Set the search list to contain the single domain

<parameter>somename</parameter>, as if specified in

a

<command>domain</command> directive in

<filename>/etc/resolv.conf</filename>, and enable

search list

processing as if the <parameter>+search</parameter>

option were given.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]search</option></term>

<listitem>

<para>

Use [do not use] the search list defined by the searchlist or

domain

directive in <filename>resolv.conf</filename> (if

any).

The search list is not used by default.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]showsearch</option></term>

<listitem>

<para>

Perform [do not perform] a search showing intermediate

results.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]defname</option></term>

<listitem>

<para>

Deprecated, treated as a synonym for <parameter>+[no]search</parameter>

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]aaonly</option></term>

<listitem>

<para>

Sets the "aa" flag in the query.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]aaflag</option></term>

<listitem>

<para>

A synonym for <parameter>+[no]aaonly</parameter>.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]adflag</option></term>

<listitem>

<para>

Set [do not set] the AD (authentic data) bit in the

query. This requests the server to return whether

all of the answer and authority sections have all

been validated as secure according to the security

policy of the server. AD=1 indicates that all records

have been validated as secure and the answer is not

from a OPT-OUT range. AD=0 indicate that some part

of the answer was insecure or not validated. This

bit is set by default.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]cdflag</option></term>

<listitem>

<para>

Set [do not set] the CD (checking disabled) bit in the query.

This

requests the server to not perform DNSSEC validation of

responses.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]cl</option></term>

<listitem>

<para>

Display [do not display] the CLASS when printing the record.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]ttlid</option></term>

<listitem>

<para>

Display [do not display] the TTL when printing the record.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]recurse</option></term>

<listitem>

<para>

Toggle the setting of the RD (recursion desired) bit

in the query. This bit is set by default, which means

<command>dig</command> normally sends recursive

queries. Recursion is automatically disabled when

the <parameter>+nssearch</parameter> or

<parameter>+trace</parameter> query options are used.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]nssearch</option></term>

<listitem>

<para>

When this option is set, <command>dig</command>

attempts to find the

authoritative name servers for the zone containing the name

being

looked up and display the SOA record that each name server has

for the

zone.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]trace</option></term>

<listitem>

<para>

Toggle tracing of the delegation path from the root

name servers for the name being looked up. Tracing

is disabled by default. When tracing is enabled,

<command>dig</command> makes iterative queries to

resolve the name being looked up. It will follow

referrals from the root servers, showing the answer

from each server that was used to resolve the lookup.

</para>

<para>

<command>+dnssec</command> is also set when +trace is

set to better emulate the default queries from a nameserver.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]cmd</option></term>

<listitem>

<para>

Toggles the printing of the initial comment in the output

identifying

the version of <command>dig</command> and the query

options that have

been applied. This comment is printed by default.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]short</option></term>

<listitem>

<para>

Provide a terse answer. The default is to print the answer in a

verbose form.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]identify</option></term>

<listitem>

<para>

Show [or do not show] the IP address and port number that

supplied the

answer when the <parameter>+short</parameter> option

is enabled. If

short form answers are requested, the default is not to show the

source address and port number of the server that provided the

answer.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]comments</option></term>

<listitem>

<para>

Toggle the display of comment lines in the output. The default

is to print comments.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]rrcomments</option></term>

<listitem>

<para>

Toggle the display of per-record comments in the output (for

example, human-readable key information about DNSKEY records).

The default is not to print record comments unless multiline

mode is active.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]crypto</option></term>

<listitem>

<para>

Toggle the display of cryptographic fields in DNSSEC records.

The contents of these field are unnecessary to debug most DNSSEC

validation failures and removing them makes it easier to see

the common failures. The default is to display the fields.

When omitted they are replaced by the string "[omitted]" or

in the DNSKEY case the key id is displayed as the replacement,

e.g. "[ key id = value ]".

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+split=W</option></term>

<listitem>

<para>

Split long hex- or base64-formatted fields in resource

records into chunks of <parameter>W</parameter> characters

(where <parameter>W</parameter> is rounded up to the nearest

multiple of 4).

<parameter>+nosplit</parameter> or

<parameter>+split=0</parameter> causes fields not to be

split at all. The default is 56 characters, or 44 characters

when multiline mode is active.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]stats</option></term>

<listitem>

<para>

This query option toggles the printing of statistics: when the

query

was made, the size of the reply and so on. The default

behavior is

to print the query statistics.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]qr</option></term>

<listitem>

<para>

Print [do not print] the query as it is sent.

By default, the query is not printed.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]question</option></term>

<listitem>

<para>

Print [do not print] the question section of a query when an

answer is

returned. The default is to print the question section as a

comment.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]answer</option></term>

<listitem>

<para>

Display [do not display] the answer section of a reply. The

default

is to display it.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]authority</option></term>

<listitem>

<para>

Display [do not display] the authority section of a reply. The

default is to display it.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]additional</option></term>

<listitem>

<para>

Display [do not display] the additional section of a reply.

The default is to display it.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]all</option></term>

<listitem>

<para>

Set or clear all display flags.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+time=T</option></term>

<listitem>

<para>

Sets the timeout for a query to

<parameter>T</parameter> seconds. The default

timeout is 5 seconds.

An attempt to set <parameter>T</parameter> to less

than 1 will result

in a query timeout of 1 second being applied.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+tries=T</option></term>

<listitem>

<para>

Sets the number of times to try UDP queries to server to

<parameter>T</parameter> instead of the default, 3.

If

<parameter>T</parameter> is less than or equal to

zero, the number of

tries is silently rounded up to 1.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+retry=T</option></term>

<listitem>

<para>

Sets the number of times to retry UDP queries to server to

<parameter>T</parameter> instead of the default, 2.

Unlike

<parameter>+tries</parameter>, this does not include

the initial

query.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+ndots=D</option></term>

<listitem>

<para>

Set the number of dots that have to appear in

<parameter>name</parameter> to <parameter>D</parameter> for it to be

considered absolute. The default value is that defined using

the

ndots statement in <filename>/etc/resolv.conf</filename>, or 1 if no

ndots statement is present. Names with fewer dots are

interpreted as

relative names and will be searched for in the domains listed in

the

<option>search</option> or <option>domain</option> directive in

<filename>/etc/resolv.conf</filename>.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+bufsize=B</option></term>

<listitem>

<para>

Set the UDP message buffer size advertised using EDNS0 to

<parameter>B</parameter> bytes. The maximum and minimum sizes

of this buffer are 65535 and 0 respectively. Values outside

this range are rounded up or down appropriately.

Values other than zero will cause a EDNS query to be sent.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+edns=#</option></term>

<listitem>

<para>

Specify the EDNS version to query with. Valid values

are 0 to 255. Setting the EDNS version will cause

a EDNS query to be sent. <option>+noedns</option>

clears the remembered EDNS version. EDNS is set to

0 by default.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]multiline</option></term>

<listitem>

<para>

Print records like the SOA records in a verbose multi-line

format with human-readable comments. The default is to print

each record on a single line, to facilitate machine parsing

of the <command>dig</command> output.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]onesoa</option></term>

<listitem>

<para>

Print only one (starting) SOA record when performing

an AXFR. The default is to print both the starting and

ending SOA records.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]fail</option></term>

<listitem>

<para>

Do not try the next server if you receive a SERVFAIL. The

default is

to not try the next server which is the reverse of normal stub

resolver

behavior.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]besteffort</option></term>

<listitem>

<para>

Attempt to display the contents of messages which are malformed.

The default is to not display malformed answers.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]dnssec</option></term>

<listitem>

<para>

Requests DNSSEC records be sent by setting the DNSSEC OK bit

(DO)

in the OPT record in the additional section of the query.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]sigchase</option></term>

<listitem>

<para>

Chase DNSSEC signature chains. Requires dig be compiled with

-DDIG_SIGCHASE.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+trusted-key=####</option></term>

<listitem>

<para>

Specifies a file containing trusted keys to be used with

<option>+sigchase</option>. Each DNSKEY record must be

on its own line.

</para>

<para>

If not specified, <command>dig</command> will look for

<filename>/etc/trusted-key.key</filename> then

<filename>trusted-key.key</filename> in the current directory.

</para>

<para>

Requires dig be compiled with -DDIG_SIGCHASE.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]topdown</option></term>

<listitem>

<para>

When chasing DNSSEC signature chains perform a top-down

validation.

Requires dig be compiled with -DDIG_SIGCHASE.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]nsid</option></term>

<listitem>

<para>

Include an EDNS name server ID request when sending a query.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]keepopen</option></term>

<listitem>

<para>

Keep the TCP socket open between queries and reuse it rather

than creating a new TCP socket for each lookup. The default

is <option>+nokeepopen</option>.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]sit<optional>=####</optional></option></term>

<listitem>

<para>

Send a Source Identity Token EDNS option, with optional value.

Replaying a SIT from a previous response will allow the

server to identify a previous client. The default is

<option>+nosit</option>.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><option>+[no]subnet=addr/prefix</option></term>

<listitem>

<para>

Send an EDNS Client Subnet option with the speciifed

IP address or network prefix.

</para>

</listitem>

</varlistentry>

</variablelist>

</para>

</refsect1>

<refsect1>

<title>MULTIPLE QUERIES</title>

<para>

The BIND 9 implementation of <command>dig </command>

supports

specifying multiple queries on the command line (in addition to

supporting the <option>-f</option> batch file option). Each of those

queries can be supplied with its own set of flags, options and query

options.

</para>

<para>

In this case, each <parameter>query</parameter> argument

represent an

individual query in the command-line syntax described above. Each

consists of any of the standard options and flags, the name to be

looked up, an optional query type and class and any query options that

should be applied to that query.

</para>

<para>

A global set of query options, which should be applied to all queries,

can also be supplied. These global query options must precede the

first tuple of name, class, type, options, flags, and query options

supplied on the command line. Any global query options (except

the <option>+[no]cmd</option> option) can be

overridden by a query-specific set of query options. For example:

<programlisting>

dig +qr www.isc.org any -x 127.0.0.1 isc.org ns +noqr

</programlisting>

shows how <command>dig</command> could be used from the

command line

to make three lookups: an ANY query for <literal>www.isc.org</literal>, a

reverse lookup of 127.0.0.1 and a query for the NS records of

<literal>isc.org</literal>.

A global query option of <parameter>+qr</parameter> is

applied, so

that <command>dig</command> shows the initial query it made

for each

lookup. The final query has a local query option of

<parameter>+noqr</parameter> which means that <command>dig</command>

will not print the initial query when it looks up the NS records for

<literal>isc.org</literal>.

</para>

</refsect1>

<refsect1>

<title>IDN SUPPORT</title>

<para>

If <command>dig</command> has been built with IDN (internationalized

domain name) support, it can accept and display non-ASCII domain names.

<command>dig</command> appropriately converts character encoding of

domain name before sending a request to DNS server or displaying a

reply from the server.

If you'd like to turn off the IDN support for some reason, defines

the <envar>IDN_DISABLE</envar> environment variable.

The IDN support is disabled if the variable is set when

<command>dig</command> runs.

</para>

</refsect1>

<refsect1>

<title>FILES</title>

<para><filename>/etc/resolv.conf</filename>

</para>

<para><filename>${HOME}/.digrc</filename>

</para>

</refsect1>

<refsect1>

<title>SEE ALSO</title>

<para><citerefentry>

<refentrytitle>host</refentrytitle><manvolnum>1</manvolnum>

</citerefentry>,

<citerefentry>

<refentrytitle>named</refentrytitle><manvolnum>8</manvolnum>

</citerefentry>,

<citerefentry>

<refentrytitle>dnssec-keygen</refentrytitle><manvolnum>8</manvolnum>

</citerefentry>,

<citetitle>RFC1035</citetitle>.

</para>

</refsect1>

<refsect1>

<title>BUGS</title>

<para>

There are probably too many query options.

</para>

</refsect1>

</refentry><!--