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diff --git a/bin/dig/host.html b/bin/dig/host.html new file mode 100644 index 0000000..6d14ef5 --- /dev/null +++ b/bin/dig/host.html @@ -0,0 +1,212 @@ +<!-- + - Copyright (C) 2004, 2005, 2007, 2008 Internet Systems Consortium, Inc. ("ISC") + - Copyright (C) 2000-2002 Internet Software Consortium. + - + - Permission to use, copy, modify, and distribute this software for any + - purpose with or without fee is hereby granted, provided that the above + - copyright notice and this permission notice appear in all copies. + - + - THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH + - REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY + - AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, + - INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM + - LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE + - OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR + - PERFORMANCE OF THIS SOFTWARE. +--> +<!-- $Id: host.html,v 1.28 2008/04/05 01:09:34 tbox Exp $ --> +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> +<title>host</title> +<meta name="generator" content="DocBook XSL Stylesheets V1.71.1"> +</head> +<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="refentry" lang="en"> +<a name="man.host"></a><div class="titlepage"></div> +<div class="refnamediv"> +<h2>Name</h2> +<p>host — DNS lookup utility</p> +</div> +<div class="refsynopsisdiv"> +<h2>Synopsis</h2> +<div class="cmdsynopsis"><p><code class="command">host</code> [<code class="option">-aCdlnrsTwv</code>] [<code class="option">-c <em class="replaceable"><code>class</code></em></code>] [<code class="option">-N <em class="replaceable"><code>ndots</code></em></code>] [<code class="option">-R <em class="replaceable"><code>number</code></em></code>] [<code class="option">-t <em class="replaceable"><code>type</code></em></code>] [<code class="option">-W <em class="replaceable"><code>wait</code></em></code>] [<code class="option">-m <em class="replaceable"><code>flag</code></em></code>] [<code class="option">-4</code>] [<code class="option">-6</code>] {name} [server]</p></div> +</div> +<div class="refsect1" lang="en"> +<a name="id2543431"></a><h2>DESCRIPTION</h2> +<p><span><strong class="command">host</strong></span> + is a simple utility for performing DNS lookups. + It is normally used to convert names to IP addresses and vice versa. + When no arguments or options are given, + <span><strong class="command">host</strong></span> + prints a short summary of its command line arguments and options. + </p> +<p><em class="parameter"><code>name</code></em> is the domain name that is to be + looked + up. It can also be a dotted-decimal IPv4 address or a colon-delimited + IPv6 address, in which case <span><strong class="command">host</strong></span> will by + default + perform a reverse lookup for that address. + <em class="parameter"><code>server</code></em> is an optional argument which + is either + the name or IP address of the name server that <span><strong class="command">host</strong></span> + should query instead of the server or servers listed in + <code class="filename">/etc/resolv.conf</code>. + </p> +<p> + The <code class="option">-a</code> (all) option is equivalent to setting the + <code class="option">-v</code> option and asking <span><strong class="command">host</strong></span> to make + a query of type ANY. + </p> +<p> + When the <code class="option">-C</code> option is used, <span><strong class="command">host</strong></span> + will attempt to display the SOA records for zone + <em class="parameter"><code>name</code></em> from all the listed + authoritative name + servers for that zone. The list of name servers is defined by the NS + records that are found for the zone. + </p> +<p> + The <code class="option">-c</code> option instructs to make a DNS query of class + <em class="parameter"><code>class</code></em>. This can be used to lookup + Hesiod or + Chaosnet class resource records. The default class is IN (Internet). + </p> +<p> + Verbose output is generated by <span><strong class="command">host</strong></span> when + the + <code class="option">-d</code> or <code class="option">-v</code> option is used. The two + options are equivalent. They have been provided for backwards + compatibility. In previous versions, the <code class="option">-d</code> option + switched on debugging traces and <code class="option">-v</code> enabled verbose + output. + </p> +<p> + List mode is selected by the <code class="option">-l</code> option. This makes + <span><strong class="command">host</strong></span> perform a zone transfer for zone + <em class="parameter"><code>name</code></em>. Transfer the zone printing out + the NS, PTR + and address records (A/AAAA). If combined with <code class="option">-a</code> + all records will be printed. + </p> +<p> + The <code class="option">-i</code> + option specifies that reverse lookups of IPv6 addresses should + use the IP6.INT domain as defined in RFC1886. + The default is to use IP6.ARPA. + </p> +<p> + The <code class="option">-N</code> option sets the number of dots that have to be + in <em class="parameter"><code>name</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 <span class="type">search</span> + or <span class="type">domain</span> directive in + <code class="filename">/etc/resolv.conf</code>. + </p> +<p> + The number of UDP retries for a lookup can be changed with the + <code class="option">-R</code> option. <em class="parameter"><code>number</code></em> + indicates + how many times <span><strong class="command">host</strong></span> will repeat a query + that does + not get answered. The default number of retries is 1. If + <em class="parameter"><code>number</code></em> is negative or zero, the + number of + retries will default to 1. + </p> +<p> + Non-recursive queries can be made via the <code class="option">-r</code> option. + Setting this option clears the <span class="type">RD</span> — recursion + desired — bit in the query which <span><strong class="command">host</strong></span> makes. + This should mean that the name server receiving the query will not + attempt to resolve <em class="parameter"><code>name</code></em>. The + <code class="option">-r</code> option enables <span><strong class="command">host</strong></span> + to mimic + the behavior of a name server by making non-recursive queries and + expecting to receive answers to those queries that are usually + referrals to other name servers. + </p> +<p> + By default <span><strong class="command">host</strong></span> uses UDP when making + queries. The + <code class="option">-T</code> option makes it use a TCP connection when querying + the name server. TCP will be automatically selected for queries that + require it, such as zone transfer (AXFR) requests. + </p> +<p> + The <code class="option">-4</code> option forces <span><strong class="command">host</strong></span> to only + use IPv4 query transport. The <code class="option">-6</code> option forces + <span><strong class="command">host</strong></span> to only use IPv6 query transport. + </p> +<p> + The <code class="option">-t</code> option is used to select the query type. + <em class="parameter"><code>type</code></em> can be any recognized query + type: CNAME, + NS, SOA, SIG, KEY, AXFR, etc. When no query type is specified, + <span><strong class="command">host</strong></span> automatically selects an appropriate + query + type. By default it looks for A, AAAA, and MX records, but if the + <code class="option">-C</code> option was given, queries will be made for SOA + records, and if <em class="parameter"><code>name</code></em> is a + dotted-decimal IPv4 + address or colon-delimited IPv6 address, <span><strong class="command">host</strong></span> will + query for PTR records. If a query type of IXFR is chosen the starting + serial number can be specified by appending an equal followed by the + starting serial number (e.g. -t IXFR=12345678). + </p> +<p> + The time to wait for a reply can be controlled through the + <code class="option">-W</code> and <code class="option">-w</code> options. The + <code class="option">-W</code> option makes <span><strong class="command">host</strong></span> + wait for + <em class="parameter"><code>wait</code></em> seconds. If <em class="parameter"><code>wait</code></em> + is less than one, the wait interval is set to one second. When the + <code class="option">-w</code> option is used, <span><strong class="command">host</strong></span> + will + effectively wait forever for a reply. The time to wait for a response + will be set to the number of seconds given by the hardware's maximum + value for an integer quantity. + </p> +<p> + The <code class="option">-s</code> option tells <span><strong class="command">host</strong></span> + <span class="emphasis"><em>not</em></span> to send the query to the next nameserver + if any server responds with a SERVFAIL response, which is the + reverse of normal stub resolver behavior. + </p> +<p> + The <code class="option">-m</code> can be used to set the memory usage debugging + flags + <em class="parameter"><code>record</code></em>, <em class="parameter"><code>usage</code></em> and + <em class="parameter"><code>trace</code></em>. + </p> +</div> +<div class="refsect1" lang="en"> +<a name="id2543797"></a><h2>IDN SUPPORT</h2> +<p> + If <span><strong class="command">host</strong></span> has been built with IDN (internationalized + domain name) support, it can accept and display non-ASCII domain names. + <span><strong class="command">host</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">host</strong></span> runs. + </p> +</div> +<div class="refsect1" lang="en"> +<a name="id2543819"></a><h2>FILES</h2> +<p><code class="filename">/etc/resolv.conf</code> + </p> +</div> +<div class="refsect1" lang="en"> +<a name="id2543831"></a><h2>SEE ALSO</h2> +<p><span class="citerefentry"><span class="refentrytitle">dig</span>(1)</span>, + <span class="citerefentry"><span class="refentrytitle">named</span>(8)</span>. + </p> +</div> +</div></body> +</html> |