man.lwresd.html revision c2258eedf2d9d0207b45b90014f8fde5413b41a3
5347c0fcb04eaea19d9f39795646239f487c6207Tinderbox User - Copyright (C) 2000-2015 Internet Systems Consortium, Inc. ("ISC")
5347c0fcb04eaea19d9f39795646239f487c6207Tinderbox User - This Source Code Form is subject to the terms of the Mozilla Public
5347c0fcb04eaea19d9f39795646239f487c6207Tinderbox User - License, v. 2.0. If a copy of the MPL was not distributed with this
5347c0fcb04eaea19d9f39795646239f487c6207Tinderbox User - file, You can obtain one at http://mozilla.org/MPL/2.0/.
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<meta name="generator" content="DocBook XSL Stylesheets V1.78.1">
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt<link rel="home" href="Bv9ARM.html" title="BIND 9 Administrator Reference Manual">
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User<link rel="up" href="Bv9ARM.ch13.html" title="Manual pages">
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt<link rel="prev" href="man.dnssec-verify.html" title="dnssec-verify">
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt<link rel="next" href="man.named.html" title="named">
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User<table width="100%" summary="Navigation header">
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User<tr><th colspan="3" align="center"><span class="application">lwresd</span></th></tr>
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt<a accesskey="p" href="man.dnssec-verify.html">Prev</a>�</td>
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User<th width="60%" align="center">Manual pages</th>
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt<td width="20%" align="right">�<a accesskey="n" href="man.named.html">Next</a>
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User<a name="man.lwresd"></a><div class="titlepage"></div>
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<p><span class="application">lwresd</span> — lightweight resolver daemon</p>
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<div class="cmdsynopsis"><p><code class="command">lwresd</code> [<code class="option">-c <em class="replaceable"><code>config-file</code></em></code>] [<code class="option">-C <em class="replaceable"><code>config-file</code></em></code>] [<code class="option">-d <em class="replaceable"><code>debug-level</code></em></code>] [<code class="option">-f</code>] [<code class="option">-g</code>] [<code class="option">-i <em class="replaceable"><code>pid-file</code></em></code>] [<code class="option">-m <em class="replaceable"><code>flag</code></em></code>] [<code class="option">-n <em class="replaceable"><code>#cpus</code></em></code>] [<code class="option">-P <em class="replaceable"><code>port</code></em></code>] [<code class="option">-p <em class="replaceable"><code>port</code></em></code>] [<code class="option">-s</code>] [<code class="option">-t <em class="replaceable"><code>directory</code></em></code>] [<code class="option">-u <em class="replaceable"><code>user</code></em></code>] [<code class="option">-v</code>] [<code class="option">-4</code>] [<code class="option">-6</code>]</p></div>
1e9517ea2156b990be21f44676d3370318eacf17Tinderbox User<a name="id-1.14.16.7"></a><h2>DESCRIPTION</h2>
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<p><span class="command"><strong>lwresd</strong></span>
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User is the daemon providing name lookup
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User services to clients that use the BIND 9 lightweight resolver
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User library. It is essentially a stripped-down, caching-only name
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User server that answers queries using the BIND 9 lightweight
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User resolver protocol rather than the DNS protocol.
9d557856c2a19ec95ee73245f60a92f8675cf5baTinderbox User<p><span class="command"><strong>lwresd</strong></span>
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User listens for resolver queries on a
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User UDP port on the IPv4 loopback interface, 127.0.0.1. This
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt means that <span class="command"><strong>lwresd</strong></span> can only be used by
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User processes running on the local machine. By default, UDP port
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User number 921 is used for lightweight resolver requests and
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User Incoming lightweight resolver requests are decoded by the
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User server which then resolves them using the DNS protocol. When
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt the DNS lookup completes, <span class="command"><strong>lwresd</strong></span> encodes
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User the answers in the lightweight resolver format and returns
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User them to the client that made the request.
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User If <code class="filename">/etc/resolv.conf</code> contains any
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt <code class="option">nameserver</code> entries, <span class="command"><strong>lwresd</strong></span>
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User sends recursive DNS queries to those servers. This is similar
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User to the use of forwarders in a caching name server. If no
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User <code class="option">nameserver</code> entries are present, or if
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt forwarding fails, <span class="command"><strong>lwresd</strong></span> resolves the
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User queries autonomously starting at the root name servers, using
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User a built-in list of root server hints.
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<div class="variablelist"><dl class="variablelist">
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User Use IPv4 only even if the host machine is capable of IPv6.
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User <code class="option">-4</code> and <code class="option">-6</code> are mutually
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User Use IPv6 only even if the host machine is capable of IPv4.
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User <code class="option">-4</code> and <code class="option">-6</code> are mutually
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User<dt><span class="term">-c <em class="replaceable"><code>config-file</code></em></span></dt>
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User Use <em class="replaceable"><code>config-file</code></em> as the
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User configuration file instead of the default,
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User <code class="filename">/etc/lwresd.conf</code>.
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User <code class="option">-c</code> can not be used with <code class="option">-C</code>.
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User<dt><span class="term">-C <em class="replaceable"><code>config-file</code></em></span></dt>
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User Use <em class="replaceable"><code>config-file</code></em> as the
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User configuration file instead of the default,
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User <code class="filename">/etc/resolv.conf</code>.
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User <code class="option">-C</code> can not be used with <code class="option">-c</code>.
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User<dt><span class="term">-d <em class="replaceable"><code>debug-level</code></em></span></dt>
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User Set the daemon's debug level to <em class="replaceable"><code>debug-level</code></em>.
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt Debugging traces from <span class="command"><strong>lwresd</strong></span> become
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User more verbose as the debug level increases.
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User Run the server in the foreground (i.e. do not daemonize).
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User Run the server in the foreground and force all logging
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User<dt><span class="term">-i <em class="replaceable"><code>pid-file</code></em></span></dt>
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User Use <em class="replaceable"><code>pid-file</code></em> as the
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User PID file instead of the default,
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User <code class="filename">/var/run/lwresd/lwresd.pid</code>.
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User<dt><span class="term">-m <em class="replaceable"><code>flag</code></em></span></dt>
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User Turn on memory usage debugging flags. Possible flags are
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User <em class="replaceable"><code>usage</code></em>,
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User <em class="replaceable"><code>trace</code></em>,
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User <em class="replaceable"><code>record</code></em>,
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User <em class="replaceable"><code>size</code></em>, and
9d557856c2a19ec95ee73245f60a92f8675cf5baTinderbox User <em class="replaceable"><code>mctx</code></em>.
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User These correspond to the ISC_MEM_DEBUGXXXX flags described in
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User <code class="filename"><isc/mem.h></code>.
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User<dt><span class="term">-n <em class="replaceable"><code>#cpus</code></em></span></dt>
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User Create <em class="replaceable"><code>#cpus</code></em> worker threads
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User to take advantage of multiple CPUs. If not specified,
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt <span class="command"><strong>lwresd</strong></span> will try to determine the
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User number of CPUs present and create one thread per CPU.
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User If it is unable to determine the number of CPUs, a
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User single worker thread will be created.
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User<dt><span class="term">-P <em class="replaceable"><code>port</code></em></span></dt>
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User Listen for lightweight resolver queries on port
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User <em class="replaceable"><code>port</code></em>. If
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User not specified, the default is port 921.
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User<dt><span class="term">-p <em class="replaceable"><code>port</code></em></span></dt>
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User Send DNS lookups to port <em class="replaceable"><code>port</code></em>. If not
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User specified, the default is port 53. This provides a
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User way of testing the lightweight resolver daemon with a
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User name server that listens for queries on a non-standard
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User Write memory usage statistics to <code class="filename">stdout</code>
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User This option is mainly of interest to BIND 9 developers
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User and may be removed or changed in a future release.
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User<dt><span class="term">-t <em class="replaceable"><code>directory</code></em></span></dt>
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User to <em class="replaceable"><code>directory</code></em> after
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User processing the command line arguments, but before
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User reading the configuration file.
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;">
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User This option should be used in conjunction with the
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User <code class="option">-u</code> option, as chrooting a process
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User running as root doesn't enhance security on most
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User systems; the way <code class="function">chroot(2)</code> is
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User defined allows a process with root privileges to
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User escape a chroot jail.
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User<dt><span class="term">-u <em class="replaceable"><code>user</code></em></span></dt>
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User to <em class="replaceable"><code>user</code></em> after completing
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User privileged operations, such as creating sockets that
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User listen on privileged ports.
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User Report the version number and exit.
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<div class="variablelist"><dl class="variablelist">
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User<dt><span class="term"><code class="filename">/etc/resolv.conf</code></span></dt>
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User The default configuration file.
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User<dt><span class="term"><code class="filename">/var/run/lwresd.pid</code></span></dt>
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User The default process-id file.
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User<p><span class="citerefentry"><span class="refentrytitle">named</span>(8)</span>,
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User <span class="citerefentry"><span class="refentrytitle">lwres</span>(3)</span>,
fd2597f75693a2279fdf588bd40dfe2407c42028Tinderbox User <span class="citerefentry"><span class="refentrytitle">resolver</span>(5)</span>.
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User<table width="100%" summary="Navigation footer">
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt<a accesskey="p" href="man.dnssec-verify.html">Prev</a>�</td>
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User<td width="20%" align="center"><a accesskey="u" href="Bv9ARM.ch13.html">Up</a></td>
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt<td width="40%" align="right">�<a accesskey="n" href="man.named.html">Next</a>
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt<span class="application">dnssec-verify</span>�</td>
9a5087bf58f651bfff841192aba5afd06760d6ceTinderbox User<td width="20%" align="center"><a accesskey="h" href="Bv9ARM.html">Home</a></td>
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt<td width="40%" align="right" valign="top">�<span class="application">named</span>
c2258eedf2d9d0207b45b90014f8fde5413b41a3Tinderbox User<p xmlns:db="http://docbook.org/ns/docbook" style="text-align: center;">BIND 9.11.0rc1</p>