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1633838b8255282d10af15c5c84cee5a51466712Bob Halley<!--
a7038d1a0513c8e804937ebc95fc9cb3a46c04f5Mark Andrews - Copyright (C) 2004-2008 Internet Systems Consortium, Inc. ("ISC")
40f53fa8d9c6a4fc38c0014495e7a42b08f52481David Lawrence - Copyright (C) 2000-2003 Internet Software Consortium.
1633838b8255282d10af15c5c84cee5a51466712Bob Halley -
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5bd76af084edfdcd1cb4db9453ac781d32dde6f7Mark Andrews<html>
9c3531d72aeaad6c5f01efe6a1c82023e1379e4dDavid Lawrence<head>
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c50fd34a4e0e6978f8ca5f6f3ad8545549c3cfeeBob Halley<title>dig</title>
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904a5734375869ffb504ed8cde6b68cafadb6d64Bob Halley</head>
e4e071ae12aee942fefc2c0a3280e402938669deBob Halley<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="refentry" lang="en">
904a5734375869ffb504ed8cde6b68cafadb6d64Bob Halley<a name="man.dig"></a><div class="titlepage"></div>
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley<div class="refnamediv">
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley<h2>Name</h2>
09f22ac5b09e70bc526015f37168ba33e21ea91fDavid Lawrence<p>dig &#8212; DNS lookup utility</p>
09f22ac5b09e70bc526015f37168ba33e21ea91fDavid Lawrence</div>
09f22ac5b09e70bc526015f37168ba33e21ea91fDavid Lawrence<div class="refsynopsisdiv">
09f22ac5b09e70bc526015f37168ba33e21ea91fDavid Lawrence<h2>Synopsis</h2>
09f22ac5b09e70bc526015f37168ba33e21ea91fDavid Lawrence<div class="cmdsynopsis"><p><code class="command">dig</code> [@server] [<code class="option">-b <em class="replaceable"><code>address</code></em></code>] [<code class="option">-c <em class="replaceable"><code>class</code></em></code>] [<code class="option">-f <em class="replaceable"><code>filename</code></em></code>] [<code class="option">-k <em class="replaceable"><code>filename</code></em></code>] [<code class="option">-p <em class="replaceable"><code>port#</code></em></code>] [<code class="option">-q <em class="replaceable"><code>name</code></em></code>] [<code class="option">-t <em class="replaceable"><code>type</code></em></code>] [<code class="option">-x <em class="replaceable"><code>addr</code></em></code>] [<code class="option">-y <em class="replaceable"><code>[<span class="optional">hmac:</span>]name:key</code></em></code>] [<code class="option">-4</code>] [<code class="option">-6</code>] [name] [type] [class] [queryopt...]</p></div>
09f22ac5b09e70bc526015f37168ba33e21ea91fDavid Lawrence<div class="cmdsynopsis"><p><code class="command">dig</code> [<code class="option">-h</code>]</p></div>
1a69a1a78cfaa86f3b68bbc965232b7876d4da2aDavid Lawrence<div class="cmdsynopsis"><p><code class="command">dig</code> [global-queryopt...] [query...]</p></div>
904a5734375869ffb504ed8cde6b68cafadb6d64Bob Halley</div>
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley<div class="refsect1" lang="en">
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley<a name="id2543511"></a><h2>DESCRIPTION</h2>
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley<p><span><strong class="command">dig</strong></span>
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington (domain information groper) is a flexible tool
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington for interrogating DNS name servers. It performs DNS lookups and
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington displays the answers that are returned from the name server(s) that
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington were queried. Most DNS administrators use <span><strong class="command">dig</strong></span> to
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington troubleshoot DNS problems because of its flexibility, ease of use and
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington clarity of output. Other lookup tools tend to have less functionality
bcff3198111e329e89cde7dac9d432b002477d80Mark Andrews than <span><strong class="command">dig</strong></span>.
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington </p>
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington<p>
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington Although <span><strong class="command">dig</strong></span> is normally used with
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington command-line
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington arguments, it also has a batch mode of operation for reading lookup
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington requests from a file. A brief summary of its command-line arguments
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington and options is printed when the <code class="option">-h</code> option is given.
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley Unlike earlier versions, the BIND 9 implementation of
84cb41f729e2a8526300dd7a6cffaa66da5cf6cdMark Andrews <span><strong class="command">dig</strong></span> allows multiple lookups to be issued
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington from the
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington command line.
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington </p>
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington<p>
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington Unless it is told to query a specific name server,
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington <span><strong class="command">dig</strong></span> will try each of the servers listed
618e871c2eb80021673bedf083496ccd1bf65cd0Brian Wellington in
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington <code class="filename">/etc/resolv.conf</code>.
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington </p>
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington<p>
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington When no command line arguments or options are given,
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington <span><strong class="command">dig</strong></span> will perform an NS query for "." (the root).
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington </p>
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington<p>
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington It is possible to set per-user defaults for <span><strong class="command">dig</strong></span> via
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington <code class="filename">${HOME}/.digrc</code>. This file is read and
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington any options in it
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley are applied before the command line arguments.
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley </p>
b55c30f2de6e1baaa3a9ba69b92f428f2c255ac3Mark Andrews<p>
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley The IN and CH class names overlap with the IN and CH top level
308c7ad5f68301d19f023af616f62f3e7cbce632Andreas Gustafsson domains names. Either use the <code class="option">-t</code> and
04b8111f2137a9cf9b0b71228f76b3e40ffa1173Brian Wellington <code class="option">-c</code> options to specify the type and class,
04b8111f2137a9cf9b0b71228f76b3e40ffa1173Brian Wellington use the <code class="option">-q</code> the specify the domain name, or
ccad3c9ecbe8a1060ff7b407a318ccd592de536eBrian Wellington use "IN." and "CH." when looking up these top level domains.
ccad3c9ecbe8a1060ff7b407a318ccd592de536eBrian Wellington </p>
ccad3c9ecbe8a1060ff7b407a318ccd592de536eBrian Wellington</div>
ccad3c9ecbe8a1060ff7b407a318ccd592de536eBrian Wellington<div class="refsect1" lang="en">
ccad3c9ecbe8a1060ff7b407a318ccd592de536eBrian Wellington<a name="id2543585"></a><h2>SIMPLE USAGE</h2>
8224be5129daebea8f0f5e8be5f925679ec893f1Brian Wellington<p>
8224be5129daebea8f0f5e8be5f925679ec893f1Brian Wellington A typical invocation of <span><strong class="command">dig</strong></span> looks like:
a413f94248ceed48a6b7aaa2fa1d2401fb8b9f30Brian Wellington </p>
d14b749789121d9d502fa1348e9e73270e9b039fBob Halley<pre class="programlisting"> dig @server name type </pre>
63d1ef9e771b748ca9bf241dfc1f07d3730203faBob Halley<p>
659175b7d430afe13b439e499442a964e2c9110fMark Andrews where:
cd02757774252fe5b92dbd59a24b34721fb49ff4Bob Halley
cd02757774252fe5b92dbd59a24b34721fb49ff4Bob Halley </p>
7b4dcbb89b71b17f5c16ca19a0e705e09509f063Bob Halley<div class="variablelist"><dl>
73af6575e00f8cf4942abce177f435797b9cfe41Brian Wellington<dt><span class="term"><code class="constant">server</code></span></dt>
322b0fb39dd1538c9f5021cd2f54d4c12684ecdbBrian Wellington<dd><p>
3864eb0e9a73148ac744893b5367169761184db5Mark Andrews is the name or IP address of the name server to query. This can
f53e43c37f2c978ccec0b49ed829426b213f9933Bob Halley be an IPv4
afbc02482008c58af2c98000209165f6880835f7Mark Andrews address in dotted-decimal notation or an IPv6
e1f16346db02486f751c6db683fffe53c866c186Andreas Gustafsson address in colon-delimited notation. When the supplied
e1f16346db02486f751c6db683fffe53c866c186Andreas Gustafsson <em class="parameter"><code>server</code></em> argument is a
2ee24549b3dddd4046ee14257e1207cf2e34f29cBrian Wellington hostname,
9ac7076ebad044afb15e9e2687e3696868778538Mark Andrews <span><strong class="command">dig</strong></span> resolves that name before
6850cdd4497424c9d42ade487edfde9fb9a47de9Brian Wellington querying that name
20a313a4581e7f85fb2ce37430a146b3538da841Mark Andrews server. If no <em class="parameter"><code>server</code></em>
20a313a4581e7f85fb2ce37430a146b3538da841Mark Andrews argument is provided,
b20ee662a7c847c9ef7b96ab9e5e34543efe5c0dMark Andrews <span><strong class="command">dig</strong></span> consults <code class="filename">/etc/resolv.conf</code>
b55c30f2de6e1baaa3a9ba69b92f428f2c255ac3Mark Andrews and queries the name servers listed there. The reply from the
e21d199dca95aff5d50f133d6b064309e209af00Brian Wellington name
6a56be50dd11702cb65347a57894ffd96a7e3501Andreas Gustafsson server that responds is displayed.
1275a72e8db349ce249c84804b2b4861d33d4db7Brian Wellington </p></dd>
15af30dfc1c54a02d252dcf4c6f3b8759eaf0327Bob Halley<dt><span class="term"><code class="constant">name</code></span></dt>
15af30dfc1c54a02d252dcf4c6f3b8759eaf0327Bob Halley<dd><p>
58cbc05eb0b80510182496ad905cd407f3624dbeBrian Wellington is the name of the resource record that is to be looked up.
a93cf7e83be621d3d68f51e37121a47a70a6757bMark Andrews </p></dd>
9ac7076ebad044afb15e9e2687e3696868778538Mark Andrews<dt><span class="term"><code class="constant">type</code></span></dt>
5ea0d11ca45bfd1ea9db8db07f18fbb02f500661Brian Wellington<dd><p>
a9ef4854464fcc56d95f72331b6e09e9563bb5f3Andreas Gustafsson indicates what type of query is required &#8212;
2c64908ae0d5b5a1cfead295d7526e7be550d3d3Mark Andrews ANY, A, MX, SIG, etc.
01446841be2b73f9a2ead74056df2d5342414041Andreas Gustafsson <em class="parameter"><code>type</code></em> can be any valid query
ff1b064f5e2bf19c8e25f8927d23df5714e666edMark Andrews type. If no
b6279d0b4b19f041b29775e637074e09f38e5e11Brian Wellington <em class="parameter"><code>type</code></em> argument is supplied,
231ffa6c85cd04d5d83f80643e26fdc3ff510138Brian Wellington <span><strong class="command">dig</strong></span> will perform a lookup for an
4b171ebd702d72200a4d7609f11c5f79d6b6f964Brian Wellington A record.
0b09763c354ec91fb352b6b4cea383bd0195b2d8Mark Andrews </p></dd>
4d9f3f00d93fcb8743b1105e8cf82e862be220d1Mark Andrews</dl></div>
5bd76af084edfdcd1cb4db9453ac781d32dde6f7Mark Andrews<p>
5bd76af084edfdcd1cb4db9453ac781d32dde6f7Mark Andrews </p>
5bd76af084edfdcd1cb4db9453ac781d32dde6f7Mark Andrews</div>
5bd76af084edfdcd1cb4db9453ac781d32dde6f7Mark Andrews<div class="refsect1" lang="en">
5bd76af084edfdcd1cb4db9453ac781d32dde6f7Mark Andrews<a name="id2543675"></a><h2>OPTIONS</h2>
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley<p>
5bd76af084edfdcd1cb4db9453ac781d32dde6f7Mark Andrews The <code class="option">-b</code> option sets the source IP address of the query
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley to <em class="parameter"><code>address</code></em>. This must be a valid
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley address on
894a2f61c9e3e51463bf21957c003d7c5636bdc5David Lawrence one of the host's network interfaces or "0.0.0.0" or "::". An optional
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley port
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley may be specified by appending "#&lt;port&gt;"
894a2f61c9e3e51463bf21957c003d7c5636bdc5David Lawrence </p>
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley<p>
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley The default query class (IN for internet) is overridden by the
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley <code class="option">-c</code> option. <em class="parameter"><code>class</code></em> is
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley any valid
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley class, such as HS for Hesiod records or CH for Chaosnet records.
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley </p>
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley<p>
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley The <code class="option">-f</code> option makes <span><strong class="command">dig </strong></span>
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley operate
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley in batch mode by reading a list of lookup requests to process from the
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley file <em class="parameter"><code>filename</code></em>. The file contains a
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley number of
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley queries, one per line. Each entry in the file should be organized in
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley the same way they would be presented as queries to
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley <span><strong class="command">dig</strong></span> using the command-line interface.
125d72976ab6b8fa6629a5ace276a86e9fef91acBrian Wellington </p>
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley<p>
25e43e68b7431d5e4ff8b5427108cd7f5f9bcf3eBob Halley If a non-standard port number is to be queried, the
c50fd34a4e0e6978f8ca5f6f3ad8545549c3cfeeBob Halley <code class="option">-p</code> option is used. <em class="parameter"><code>port#</code></em> is
09f22ac5b09e70bc526015f37168ba33e21ea91fDavid Lawrence the port number that <span><strong class="command">dig</strong></span> will send its
09f22ac5b09e70bc526015f37168ba33e21ea91fDavid Lawrence queries
6d12fdf96621801e80f3f4c2a8a569fe48766a20David Lawrence instead of the standard DNS port number 53. This option would be used
09f22ac5b09e70bc526015f37168ba33e21ea91fDavid Lawrence to test a name server that has been configured to listen for queries
09f22ac5b09e70bc526015f37168ba33e21ea91fDavid Lawrence on a non-standard port number.
09f22ac5b09e70bc526015f37168ba33e21ea91fDavid Lawrence </p>
09f22ac5b09e70bc526015f37168ba33e21ea91fDavid Lawrence<p>
09f22ac5b09e70bc526015f37168ba33e21ea91fDavid Lawrence The <code class="option">-4</code> option forces <span><strong class="command">dig</strong></span>
09f22ac5b09e70bc526015f37168ba33e21ea91fDavid Lawrence to only
09f22ac5b09e70bc526015f37168ba33e21ea91fDavid Lawrence use IPv4 query transport. The <code class="option">-6</code> option forces
c50fd34a4e0e6978f8ca5f6f3ad8545549c3cfeeBob Halley <span><strong class="command">dig</strong></span> to only use IPv6 query transport.
904a5734375869ffb504ed8cde6b68cafadb6d64Bob Halley </p>
904a5734375869ffb504ed8cde6b68cafadb6d64Bob Halley<p>
c50fd34a4e0e6978f8ca5f6f3ad8545549c3cfeeBob Halley The <code class="option">-t</code> option sets the query type to
<em class="parameter"><code>type</code></em>. It can be any valid query type
which is
supported in BIND 9. The default query type is "A", unless the
<code class="option">-x</code> 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,
<em class="parameter"><code>type</code></em> is set to <code class="literal">ixfr=N</code>.
The incremental zone transfer will contain the changes made to the zone
since the serial number in the zone's SOA record was
<em class="parameter"><code>N</code></em>.
</p>
<p>
The <code class="option">-q</code> option sets the query name to
<em class="parameter"><code>name</code></em>. This useful do distinguish the
<em class="parameter"><code>name</code></em> from other arguments.
</p>
<p>
Reverse lookups &#8212; mapping addresses to names &#8212; are simplified by the
<code class="option">-x</code> option. <em class="parameter"><code>addr</code></em> 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
<em class="parameter"><code>name</code></em>, <em class="parameter"><code>class</code></em> and
<em class="parameter"><code>type</code></em> arguments. <span><strong class="command">dig</strong></span>
automatically performs a lookup for a name like
<code class="literal">11.12.13.10.in-addr.arpa</code> 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 <code class="option">-i</code> option. Bit string labels (RFC2874)
are now experimental and are not attempted.
</p>
<p>
To sign the DNS queries sent by <span><strong class="command">dig</strong></span> and
their
responses using transaction signatures (TSIG), specify a TSIG key file
using the <code class="option">-k</code> option. You can also specify the TSIG
key itself on the command line using the <code class="option">-y</code> option;
<em class="parameter"><code>hmac</code></em> is the type of the TSIG, default HMAC-MD5,
<em class="parameter"><code>name</code></em> is the name of the TSIG key and
<em class="parameter"><code>key</code></em> is the actual key. The key is a
base-64
encoded string, typically generated by
<span class="citerefentry"><span class="refentrytitle">dnssec-keygen</span>(8)</span>.
Caution should be taken when using the <code class="option">-y</code> option on
multi-user systems as the key can be visible in the output from
<span class="citerefentry"><span class="refentrytitle">ps</span>(1)</span>
or in the shell's history file. When
using TSIG authentication with <span><strong class="command">dig</strong></span>, 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
<span><strong class="command">key</strong></span> and <span><strong class="command">server</strong></span> statements in
<code class="filename">named.conf</code>.
</p>
</div>
<div class="refsect1" lang="en">
<a name="id2543946"></a><h2>QUERY OPTIONS</h2>
<p><span><strong class="command">dig</strong></span>
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.
</p>
<p>
Each query option is identified by a keyword preceded by a plus sign
(<code class="literal">+</code>). Some keywords set or reset an
option. These may be preceded
by the string <code class="literal">no</code> to negate the meaning of
that keyword. Other
keywords assign values to options like the timeout interval. They
have the form <code class="option">+keyword=value</code>.
The query options are:
</p>
<div class="variablelist"><dl>
<dt><span class="term"><code class="option">+[no]tcp</code></span></dt>
<dd><p>
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.
</p></dd>
<dt><span class="term"><code class="option">+[no]vc</code></span></dt>
<dd><p>
Use [do not use] TCP when querying name servers. This alternate
syntax to <em class="parameter"><code>+[no]tcp</code></em> is
provided for backwards
compatibility. The "vc" stands for "virtual circuit".
</p></dd>
<dt><span class="term"><code class="option">+[no]ignore</code></span></dt>
<dd><p>
Ignore truncation in UDP responses instead of retrying with TCP.
By
default, TCP retries are performed.
</p></dd>
<dt><span class="term"><code class="option">+domain=somename</code></span></dt>
<dd><p>
Set the search list to contain the single domain
<em class="parameter"><code>somename</code></em>, as if specified in
a
<span><strong class="command">domain</strong></span> directive in
<code class="filename">/etc/resolv.conf</code>, and enable
search list
processing as if the <em class="parameter"><code>+search</code></em>
option were given.
</p></dd>
<dt><span class="term"><code class="option">+[no]search</code></span></dt>
<dd><p>
Use [do not use] the search list defined by the searchlist or
domain
directive in <code class="filename">resolv.conf</code> (if
any).
The search list is not used by default.
</p></dd>
<dt><span class="term"><code class="option">+[no]showsearch</code></span></dt>
<dd><p>
Perform [do not perform] a search showing intermediate
results.
</p></dd>
<dt><span class="term"><code class="option">+[no]defname</code></span></dt>
<dd><p>
Deprecated, treated as a synonym for <em class="parameter"><code>+[no]search</code></em>
</p></dd>
<dt><span class="term"><code class="option">+[no]aaonly</code></span></dt>
<dd><p>
Sets the "aa" flag in the query.
</p></dd>
<dt><span class="term"><code class="option">+[no]aaflag</code></span></dt>
<dd><p>
A synonym for <em class="parameter"><code>+[no]aaonly</code></em>.
</p></dd>
<dt><span class="term"><code class="option">+[no]adflag</code></span></dt>
<dd><p>
Set [do not set] the AD (authentic data) bit in the query. The
AD bit
currently has a standard meaning only in responses, not in
queries,
but the ability to set the bit in the query is provided for
completeness.
</p></dd>
<dt><span class="term"><code class="option">+[no]cdflag</code></span></dt>
<dd><p>
Set [do not set] the CD (checking disabled) bit in the query.
This
requests the server to not perform DNSSEC validation of
responses.
</p></dd>
<dt><span class="term"><code class="option">+[no]cl</code></span></dt>
<dd><p>
Display [do not display] the CLASS when printing the record.
</p></dd>
<dt><span class="term"><code class="option">+[no]ttlid</code></span></dt>
<dd><p>
Display [do not display] the TTL when printing the record.
</p></dd>
<dt><span class="term"><code class="option">+[no]recurse</code></span></dt>
<dd><p>
Toggle the setting of the RD (recursion desired) bit in the
query.
This bit is set by default, which means <span><strong class="command">dig</strong></span>
normally sends recursive queries. Recursion is automatically
disabled
when the <em class="parameter"><code>+nssearch</code></em> or
<em class="parameter"><code>+trace</code></em> query options are
used.
</p></dd>
<dt><span class="term"><code class="option">+[no]nssearch</code></span></dt>
<dd><p>
When this option is set, <span><strong class="command">dig</strong></span>
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.
</p></dd>
<dt><span class="term"><code class="option">+[no]trace</code></span></dt>
<dd><p>
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, <span><strong class="command">dig</strong></span> 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.
</p></dd>
<dt><span class="term"><code class="option">+[no]cmd</code></span></dt>
<dd><p>
Toggles the printing of the initial comment in the output
identifying
the version of <span><strong class="command">dig</strong></span> and the query
options that have
been applied. This comment is printed by default.
</p></dd>
<dt><span class="term"><code class="option">+[no]short</code></span></dt>
<dd><p>
Provide a terse answer. The default is to print the answer in a
verbose form.
</p></dd>
<dt><span class="term"><code class="option">+[no]identify</code></span></dt>
<dd><p>
Show [or do not show] the IP address and port number that
supplied the
answer when the <em class="parameter"><code>+short</code></em> 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.
</p></dd>
<dt><span class="term"><code class="option">+[no]comments</code></span></dt>
<dd><p>
Toggle the display of comment lines in the output. The default
is to
print comments.
</p></dd>
<dt><span class="term"><code class="option">+[no]stats</code></span></dt>
<dd><p>
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.
</p></dd>
<dt><span class="term"><code class="option">+[no]qr</code></span></dt>
<dd><p>
Print [do not print] the query as it is sent.
By default, the query is not printed.
</p></dd>
<dt><span class="term"><code class="option">+[no]question</code></span></dt>
<dd><p>
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.
</p></dd>
<dt><span class="term"><code class="option">+[no]answer</code></span></dt>
<dd><p>
Display [do not display] the answer section of a reply. The
default
is to display it.
</p></dd>
<dt><span class="term"><code class="option">+[no]authority</code></span></dt>
<dd><p>
Display [do not display] the authority section of a reply. The
default is to display it.
</p></dd>
<dt><span class="term"><code class="option">+[no]additional</code></span></dt>
<dd><p>
Display [do not display] the additional section of a reply.
The default is to display it.
</p></dd>
<dt><span class="term"><code class="option">+[no]all</code></span></dt>
<dd><p>
Set or clear all display flags.
</p></dd>
<dt><span class="term"><code class="option">+time=T</code></span></dt>
<dd><p>
Sets the timeout for a query to
<em class="parameter"><code>T</code></em> seconds. The default
timeout is 5 seconds.
An attempt to set <em class="parameter"><code>T</code></em> to less
than 1 will result
in a query timeout of 1 second being applied.
</p></dd>
<dt><span class="term"><code class="option">+tries=T</code></span></dt>
<dd><p>
Sets the number of times to try UDP queries to server to
<em class="parameter"><code>T</code></em> instead of the default, 3.
If
<em class="parameter"><code>T</code></em> is less than or equal to
zero, the number of
tries is silently rounded up to 1.
</p></dd>
<dt><span class="term"><code class="option">+retry=T</code></span></dt>
<dd><p>
Sets the number of times to retry UDP queries to server to
<em class="parameter"><code>T</code></em> instead of the default, 2.
Unlike
<em class="parameter"><code>+tries</code></em>, this does not include
the initial
query.
</p></dd>
<dt><span class="term"><code class="option">+ndots=D</code></span></dt>
<dd><p>
Set the number of dots that have to appear in
<em class="parameter"><code>name</code></em> to <em class="parameter"><code>D</code></em> for it to be
considered absolute. The default value is that defined using
the
ndots statement in <code class="filename">/etc/resolv.conf</code>, 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
<code class="option">search</code> or <code class="option">domain</code> directive in
<code class="filename">/etc/resolv.conf</code>.
</p></dd>
<dt><span class="term"><code class="option">+bufsize=B</code></span></dt>
<dd><p>
Set the UDP message buffer size advertised using EDNS0 to
<em class="parameter"><code>B</code></em> 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.
</p></dd>
<dt><span class="term"><code class="option">+edns=#</code></span></dt>
<dd><p>
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. <code class="option">+noedns</code> clears the
remembered EDNS version.
</p></dd>
<dt><span class="term"><code class="option">+[no]multiline</code></span></dt>
<dd><p>
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 <span><strong class="command">dig</strong></span> output.
</p></dd>
<dt><span class="term"><code class="option">+[no]fail</code></span></dt>
<dd><p>
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.
</p></dd>
<dt><span class="term"><code class="option">+[no]besteffort</code></span></dt>
<dd><p>
Attempt to display the contents of messages which are malformed.
The default is to not display malformed answers.
</p></dd>
<dt><span class="term"><code class="option">+[no]dnssec</code></span></dt>
<dd><p>
Requests DNSSEC records be sent by setting the DNSSEC OK bit
(DO)
in the OPT record in the additional section of the query.
</p></dd>
<dt><span class="term"><code class="option">+[no]sigchase</code></span></dt>
<dd><p>
Chase DNSSEC signature chains. Requires dig be compiled with
-DDIG_SIGCHASE.
</p></dd>
<dt><span class="term"><code class="option">+trusted-key=####</code></span></dt>
<dd>
<p>
Specifies a file containing trusted keys to be used with
<code class="option">+sigchase</code>. Each DNSKEY record must be
on its own line.
</p>
<p>
If not specified <span><strong class="command">dig</strong></span> will look for
<code class="filename">/etc/trusted-key.key</code> then
<code class="filename">trusted-key.key</code> in the current directory.
</p>
<p>
Requires dig be compiled with -DDIG_SIGCHASE.
</p>
</dd>
<dt><span class="term"><code class="option">+[no]topdown</code></span></dt>
<dd><p>
When chasing DNSSEC signature chains perform a top-down
validation.
Requires dig be compiled with -DDIG_SIGCHASE.
</p></dd>
<dt><span class="term"><code class="option">+[no]nsid</code></span></dt>
<dd><p>
Include an EDNS name server ID request when sending a query.
</p></dd>
</dl></div>
<p>
</p>
</div>
<div class="refsect1" lang="en">
<a name="id2545149"></a><h2>MULTIPLE QUERIES</h2>
<p>
The BIND 9 implementation of <span><strong class="command">dig </strong></span>
supports
specifying multiple queries on the command line (in addition to
supporting the <code class="option">-f</code> batch file option). Each of those
queries can be supplied with its own set of flags, options and query
options.
</p>
<p>
In this case, each <em class="parameter"><code>query</code></em> 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.
</p>
<p>
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 <code class="option">+[no]cmd</code> option) can be
overridden by a query-specific set of query options. For example:
</p>
<pre class="programlisting">
dig +qr www.isc.org any -x 127.0.0.1 isc.org ns +noqr
</pre>
<p>
shows how <span><strong class="command">dig</strong></span> could be used from the
command line
to make three lookups: an ANY query for <code class="literal">www.isc.org</code>, a
reverse lookup of 127.0.0.1 and a query for the NS records of
<code class="literal">isc.org</code>.
A global query option of <em class="parameter"><code>+qr</code></em> is
applied, so
that <span><strong class="command">dig</strong></span> shows the initial query it made
for each
lookup. The final query has a local query option of
<em class="parameter"><code>+noqr</code></em> which means that <span><strong class="command">dig</strong></span>
will not print the initial query when it looks up the NS records for
<code class="literal">isc.org</code>.
</p>
</div>
<div class="refsect1" lang="en">
<a name="id2545211"></a><h2>IDN SUPPORT</h2>
<p>
If <span><strong class="command">dig</strong></span> has been built with IDN (internationalized
domain name) support, it can accept and display non-ASCII domain names.
<span><strong class="command">dig</strong></span> 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 <code class="envar">IDN_DISABLE</code> environment variable.
The IDN support is disabled if the variable is set when
<span><strong class="command">dig</strong></span> runs.
</p>
</div>
<div class="refsect1" lang="en">
<a name="id2545234"></a><h2>FILES</h2>
<p><code class="filename">/etc/resolv.conf</code>
</p>
<p><code class="filename">${HOME}/.digrc</code>
</p>
</div>
<div class="refsect1" lang="en">
<a name="id2545251"></a><h2>SEE ALSO</h2>
<p><span class="citerefentry"><span class="refentrytitle">host</span>(1)</span>,
<span class="citerefentry"><span class="refentrytitle">named</span>(8)</span>,
<span class="citerefentry"><span class="refentrytitle">dnssec-keygen</span>(8)</span>,
<em class="citetitle">RFC1035</em>.
</p>
</div>
<div class="refsect1" lang="en">
<a name="id2545356"></a><h2>BUGS</h2>
<p>
There are probably too many query options.
</p>
</div>
</div></body>
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