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<title>dig</title>
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<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="refentry" lang="en">
<a name="man.dig"></a><div class="titlepage"></div>
<div class="refnamediv">
<h2>Name</h2>
<p>dig &#8212; DNS lookup utility</p>
</div>
<div class="refsynopsisdiv">
<h2>Synopsis</h2>
<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">-m</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>
<div class="cmdsynopsis"><p><code class="command">dig</code>  [<code class="option">-h</code>]</p></div>
<div class="cmdsynopsis"><p><code class="command">dig</code>  [global-queryopt...] [query...]</p></div>
</div>
<div class="refsect1" lang="en">
<a name="id2543530"></a><h2>DESCRIPTION</h2>
<p><span><strong class="command">dig</strong></span>
      (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 <span><strong class="command">dig</strong></span> to
      troubleshoot DNS problems because of its flexibility, ease of use and
      clarity of output.  Other lookup tools tend to have less functionality
      than <span><strong class="command">dig</strong></span>.
    </p>
<p>
      Although <span><strong class="command">dig</strong></span> 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 <code class="option">-h</code> option is given.
      Unlike earlier versions, the BIND 9 implementation of
      <span><strong class="command">dig</strong></span> allows multiple lookups to be issued
      from the
      command line.
    </p>
<p>
      Unless it is told to query a specific name server,
      <span><strong class="command">dig</strong></span> will try each of the servers listed in
      <code class="filename">/etc/resolv.conf</code>. If no usable server addresses
      are found, <span><strong class="command">dig</strong></span> will send the query to the local
      host.
    </p>
<p>
      When no command line arguments or options are given,
      <span><strong class="command">dig</strong></span> will perform an NS query for "." (the root).
    </p>
<p>
      It is possible to set per-user defaults for <span><strong class="command">dig</strong></span> via
      <code class="filename">${HOME}/.digrc</code>.  This file is read and
      any options in it
      are applied before the command line arguments.
    </p>
<p>
      The IN and CH class names overlap with the IN and CH top level
      domains names.  Either use the <code class="option">-t</code> and
      <code class="option">-c</code> options to specify the type and class, 
      use the <code class="option">-q</code> the specify the domain name, or
      use "IN." and "CH." when looking up these top level domains.
    </p>
</div>
<div class="refsect1" lang="en">
<a name="id2543609"></a><h2>SIMPLE USAGE</h2>
<p>
      A typical invocation of <span><strong class="command">dig</strong></span> looks like:
      </p>
<pre class="programlisting"> dig @server name type </pre>
<p>
      where:

      </p>
<div class="variablelist"><dl>
<dt><span class="term"><code class="constant">server</code></span></dt>
<dd>
<p>
              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
              <em class="parameter"><code>server</code></em> argument is a hostname,
              <span><strong class="command">dig</strong></span> resolves that name before querying
              that name server.
            </p>
<p>
              If no <em class="parameter"><code>server</code></em> argument is
              provided, <span><strong class="command">dig</strong></span> consults
              <code class="filename">/etc/resolv.conf</code>; if an
              address is found there, it queries the name server at
              that address. If either of the <code class="option">-4</code> or
              <code class="option">-6</code> options are in use, then
              only addresses for the corresponding transport
              will be tried.  If no usable addresses are found,
              <span><strong class="command">dig</strong></span> will send the query to the
              local host.  The reply from the name server that
              responds is displayed.
            </p>
</dd>
<dt><span class="term"><code class="constant">name</code></span></dt>
<dd><p>
              is the name of the resource record that is to be looked up.
            </p></dd>
<dt><span class="term"><code class="constant">type</code></span></dt>
<dd><p>
              indicates what type of query is required &#8212;
              ANY, A, MX, SIG, etc.
              <em class="parameter"><code>type</code></em> can be any valid query
              type.  If no
              <em class="parameter"><code>type</code></em> argument is supplied,
              <span><strong class="command">dig</strong></span> will perform a lookup for an
              A record.
            </p></dd>
</dl></div>
<p>
    </p>
</div>
<div class="refsect1" lang="en">
<a name="id2543713"></a><h2>OPTIONS</h2>
<p>
      The <code class="option">-b</code> option sets the source IP address of the query
      to <em class="parameter"><code>address</code></em>.  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;"
    </p>
<p>
      The default query class (IN for internet) is overridden by the
      <code class="option">-c</code> option.  <em class="parameter"><code>class</code></em> is
      any valid
      class, such as HS for Hesiod records or CH for Chaosnet records.
    </p>
<p>
      The <code class="option">-f</code> option makes <span><strong class="command">dig </strong></span>
      operate
      in batch mode by reading a list of lookup requests to process from the
      file <em class="parameter"><code>filename</code></em>.  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
      <span><strong class="command">dig</strong></span> using the command-line interface.
    </p>
<p>
      The <code class="option">-m</code> option enables memory usage debugging.
      
    </p>
<p>
      If a non-standard port number is to be queried, the
      <code class="option">-p</code> option is used.  <em class="parameter"><code>port#</code></em> is
      the port number that <span><strong class="command">dig</strong></span> 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.
    </p>
<p>
      The <code class="option">-4</code> option forces <span><strong class="command">dig</strong></span>
      to only
      use IPv4 query transport.  The <code class="option">-6</code> option forces
      <span><strong class="command">dig</strong></span> to only use IPv6 query transport.
    </p>
<p>
      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="id2544061"></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.  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.
	    </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>
<p>
	      <span><strong class="command">+dnssec</strong></span> is also set when +trace is
	      set to better emulate the default queries from a nameserver.
	    </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]rrcomments</code></span></dt>
<dd><p>
              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.
            </p></dd>
<dt><span class="term"><code class="option">+split=W</code></span></dt>
<dd><p>
              Split long hex- or base64-formatted fields in resource
              records into chunks of <em class="parameter"><code>W</code></em> characters
              (where <em class="parameter"><code>W</code></em> is rounded up to the nearest
              multiple of 4).
              <em class="parameter"><code>+nosplit</code></em> or
              <em class="parameter"><code>+split=0</code></em> causes fields not to be
              split at all.  The default is 56 characters, or 44 characters
              when multiline mode is active.
            </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.  EDNS is set to
	       0 by default.
	    </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]onesoa</code></span></dt>
<dd><p>
	      Print only one (starting) SOA record when performing
	      an AXFR. The default is to print both the starting and
	      ending SOA records.
	    </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>
<dt><span class="term"><code class="option">+[no]keepopen</code></span></dt>
<dd><p>
              Keep the TCP socket open between queries and reuse it rather
	      than creating a new TCP socket for each lookup.  The default
	      is <code class="option">+nokeepopen</code>.
            </p></dd>
</dl></div>
<p>

    </p>
</div>
<div class="refsect1" lang="en">
<a name="id2545341"></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="id2545403"></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="id2545426"></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="id2545443"></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="id2545548"></a><h2>BUGS</h2>
<p>
      There are probably too many query options.
    </p>
</div>
</div></body>
</html>