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869a36e2649ae064c98063cf1e55198488d78d12Allan Foster - Copyright (C) 2004, 2005 Internet Systems Consortium, Inc. ("ISC")
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster - Copyright (C) 2000-2003 Internet Software Consortium.
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster - Permission to use, copy, modify, and distribute this software for any
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster - purpose with or without fee is hereby granted, provided that the above
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster - copyright notice and this permission notice appear in all copies.
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster - THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster - REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster - AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster - INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster - LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
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869a36e2649ae064c98063cf1e55198488d78d12Allan Foster - PERFORMANCE OF THIS SOFTWARE.
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster<!-- $Id: dig.html,v 1.26 2005/08/25 03:12:43 marka Exp $ -->
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869a36e2649ae064c98063cf1e55198488d78d12Allan Foster<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="refentry" lang="en">
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster<a name="man.dig"></a><div class="titlepage"></div>
6909255a1970175507277a0f2f105979625f76b2Jaco Jooste<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>name:key</code></em></code>] [<code class="option">-4</code>] [<code class="option">-6</code>] [name] [type] [class] [queryopt...]</p></div>
6909255a1970175507277a0f2f105979625f76b2Jaco Jooste<div class="cmdsynopsis"><p><code class="command">dig</code> [<code class="option">-h</code>]</p></div>
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster<div class="cmdsynopsis"><p><code class="command">dig</code> [global-queryopt...] [query...]</p></div>
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster<p><span><strong class="command">dig</strong></span>
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster (domain information groper) is a flexible tool
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster for interrogating DNS name servers. It performs DNS lookups and
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster displays the answers that are returned from the name server(s) that
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster were queried. Most DNS administrators use <span><strong class="command">dig</strong></span> to
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster troubleshoot DNS problems because of its flexibility, ease of use and
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster clarity of output. Other lookup tools tend to have less functionality
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster than <span><strong class="command">dig</strong></span>.
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster Although <span><strong class="command">dig</strong></span> is normally used with
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster command-line
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster arguments, it also has a batch mode of operation for reading lookup
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster requests from a file. A brief summary of its command-line arguments
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster and options is printed when the <code class="option">-h</code> option is given.
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster Unlike earlier versions, the BIND9 implementation of
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <span><strong class="command">dig</strong></span> allows multiple lookups to be issued
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster command line.
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster Unless it is told to query a specific name server,
6909255a1970175507277a0f2f105979625f76b2Jaco Jooste <span><strong class="command">dig</strong></span> will try each of the servers listed
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <code class="filename">/etc/resolv.conf</code>.
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster When no command line arguments or options are given, will perform an
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster NS query for "." (the root).
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster It is possible to set per-user defaults for <span><strong class="command">dig</strong></span> via
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <code class="filename">${HOME}/.digrc</code>. This file is read and
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster any options in it
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster are applied before the command line arguments.
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster A typical invocation of <span><strong class="command">dig</strong></span> looks like:
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster<pre class="programlisting"> dig @server name type </pre>
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster<dt><span class="term"><code class="constant">server</code></span></dt>
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster is the name or IP address of the name server to query. This can
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster address in dotted-decimal notation or an IPv6
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster address in colon-delimited notation. When the supplied
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <em class="parameter"><code>server</code></em> argument is a
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <span><strong class="command">dig</strong></span> resolves that name before
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster querying that name
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster server. If no <em class="parameter"><code>server</code></em>
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster argument is provided,
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <span><strong class="command">dig</strong></span> consults <code class="filename">/etc/resolv.conf</code>
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster and queries the name servers listed there. The reply from the
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster server that responds is displayed.
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster<dt><span class="term"><code class="constant">name</code></span></dt>
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster is the name of the resource record that is to be looked up.
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster<dt><span class="term"><code class="constant">type</code></span></dt>
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster indicates what type of query is required —
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster ANY, A, MX, SIG, etc.
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <em class="parameter"><code>type</code></em> can be any valid query
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <em class="parameter"><code>type</code></em> argument is supplied,
d1b57e78cf72f41c7c6a52bd7c2a6d6aa4da6ba4Craig McDonnell <span><strong class="command">dig</strong></span> will perform a lookup for an
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster The <code class="option">-b</code> option sets the source IP address of the query
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster to <em class="parameter"><code>address</code></em>. This must be a valid
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster one of the host's network interfaces or "0.0.0.0" or "::". An optional
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster may be specified by appending "#<port>"
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster The default query class (IN for internet) is overridden by the
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <code class="option">-c</code> option. <em class="parameter"><code>class</code></em> is
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster class, such as HS for Hesiod records or CH for CHAOSNET records.
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster The <code class="option">-f</code> option makes <span><strong class="command">dig </strong></span>
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster in batch mode by reading a list of lookup requests to process from the
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster file <em class="parameter"><code>filename</code></em>. The file contains a
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster queries, one per line. Each entry in the file should be organised in
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster the same way they would be presented as queries to
d1b57e78cf72f41c7c6a52bd7c2a6d6aa4da6ba4Craig McDonnell <span><strong class="command">dig</strong></span> using the command-line interface.
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster If a non-standard port number is to be queried, the
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <code class="option">-p</code> option is used. <em class="parameter"><code>port#</code></em> is
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster the port number that <span><strong class="command">dig</strong></span> will send its
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster instead of the standard DNS port number 53. This option would be used
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster to test a name server that has been configured to listen for queries
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster on a non-standard port number.
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster The <code class="option">-4</code> option forces <span><strong class="command">dig</strong></span>
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster use IPv4 query transport. The <code class="option">-6</code> option forces
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <span><strong class="command">dig</strong></span> to only use IPv6 query transport.
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster The <code class="option">-t</code> option sets the query type to
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <em class="parameter"><code>type</code></em>. It can be any valid query type
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster supported in BIND9. The default query type "A", unless the
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <code class="option">-x</code> option is supplied to indicate a reverse lookup.
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster A zone transfer can be requested by specifying a type of AXFR. When
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster an incremental zone transfer (IXFR) is required,
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <em class="parameter"><code>type</code></em> is set to <code class="literal">ixfr=N</code>.
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster The incremental zone transfer will contain the changes made to the zone
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster since the serial number in the zone's SOA record was
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster The <code class="option">-q</code> option sets the query name to
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <em class="parameter"><code>name</code></em>. This useful do distingish the
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <em class="parameter"><code>name</code></em> from other arguements.
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster Reverse lookups - mapping addresses to names - are simplified by the
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <code class="option">-x</code> option. <em class="parameter"><code>addr</code></em> is
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster address in dotted-decimal notation, or a colon-delimited IPv6 address.
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster When this option is used, there is no need to provide the
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <em class="parameter"><code>name</code></em>, <em class="parameter"><code>class</code></em> and
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <em class="parameter"><code>type</code></em> arguments. <span><strong class="command">dig</strong></span>
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster automatically performs a lookup for a name like
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <code class="literal">11.12.13.10.in-addr.arpa</code> and sets the
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster query type and
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster class to PTR and IN respectively. By default, IPv6 addresses are
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster looked up using nibble format under the IP6.ARPA domain.
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster To use the older RFC1886 method using the IP6.INT domain
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster specify the <code class="option">-i</code> option. Bit string labels (RFC2874)
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster are now experimental and are not attempted.
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster To sign the DNS queries sent by <span><strong class="command">dig</strong></span> and
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster responses using transaction signatures (TSIG), specify a TSIG key file
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster using the <code class="option">-k</code> option. You can also specify the TSIG
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster key itself on the command line using the <code class="option">-y</code> option;
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <em class="parameter"><code>name</code></em> is the name of the TSIG key and
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <em class="parameter"><code>key</code></em> is the actual key. The key is a
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster encoded string, typically generated by
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <span class="citerefentry"><span class="refentrytitle">dnssec-keygen</span>(8)</span>.
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster Caution should be taken when using the <code class="option">-y</code> option on
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster multi-user systems as the key can be visible in the output from
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <span class="citerefentry"><span class="refentrytitle">ps</span>(1)</span>
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster or in the shell's history file. When
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster using TSIG authentication with <span><strong class="command">dig</strong></span>, the name
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster server that is queried needs to know the key and algorithm that is
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster being used. In BIND, this is done by providing appropriate
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster <span><strong class="command">key</strong></span> and <span><strong class="command">server</strong></span> statements in
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster<p><span><strong class="command">dig</strong></span>
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster provides a number of query options which affect
869a36e2649ae064c98063cf1e55198488d78d12Allan Foster the way in which lookups are made and the results displayed. Some of
<em class="parameter"><code>name</code></em> to <em class="parameter"><code>D</code></em> for it to be