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783393527e6a36415efb92e94a148c96b539e582vboxsync - Copyright (C) 2004, 2005, 2007-2009, 2014, 2015 Internet Systems Consortium, Inc. ("ISC")
783393527e6a36415efb92e94a148c96b539e582vboxsync - Copyright (C) 2000, 2001 Internet Software Consortium.
783393527e6a36415efb92e94a148c96b539e582vboxsync - Permission to use, copy, modify, and/or distribute this software for any
783393527e6a36415efb92e94a148c96b539e582vboxsync - purpose with or without fee is hereby granted, provided that the above
783393527e6a36415efb92e94a148c96b539e582vboxsync - copyright notice and this permission notice appear in all copies.
783393527e6a36415efb92e94a148c96b539e582vboxsync - THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
783393527e6a36415efb92e94a148c96b539e582vboxsync - REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
783393527e6a36415efb92e94a148c96b539e582vboxsync - AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
783393527e6a36415efb92e94a148c96b539e582vboxsync - INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
783393527e6a36415efb92e94a148c96b539e582vboxsync - LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
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783393527e6a36415efb92e94a148c96b539e582vboxsync - PERFORMANCE OF THIS SOFTWARE.
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783393527e6a36415efb92e94a148c96b539e582vboxsync<a name="man.lwresd"></a><div class="titlepage"></div>
783393527e6a36415efb92e94a148c96b539e582vboxsync<p><span class="application">lwresd</span> — lightweight resolver daemon</p>
783393527e6a36415efb92e94a148c96b539e582vboxsync<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>
0bfb99a63b33971b6285648db35f5562705966d9vboxsync<p><span><strong class="command">lwresd</strong></span>
0bfb99a63b33971b6285648db35f5562705966d9vboxsync is the daemon providing name lookup
0bfb99a63b33971b6285648db35f5562705966d9vboxsync services to clients that use the BIND 9 lightweight resolver
783393527e6a36415efb92e94a148c96b539e582vboxsync library. It is essentially a stripped-down, caching-only name
783393527e6a36415efb92e94a148c96b539e582vboxsync server that answers queries using the BIND 9 lightweight
783393527e6a36415efb92e94a148c96b539e582vboxsync resolver protocol rather than the DNS protocol.
783393527e6a36415efb92e94a148c96b539e582vboxsync<p><span><strong class="command">lwresd</strong></span>
783393527e6a36415efb92e94a148c96b539e582vboxsync listens for resolver queries on a
783393527e6a36415efb92e94a148c96b539e582vboxsync UDP port on the IPv4 loopback interface, 127.0.0.1. This
783393527e6a36415efb92e94a148c96b539e582vboxsync means that <span><strong class="command">lwresd</strong></span> can only be used by
783393527e6a36415efb92e94a148c96b539e582vboxsync processes running on the local machine. By default, UDP port
783393527e6a36415efb92e94a148c96b539e582vboxsync number 921 is used for lightweight resolver requests and
783393527e6a36415efb92e94a148c96b539e582vboxsync Incoming lightweight resolver requests are decoded by the
783393527e6a36415efb92e94a148c96b539e582vboxsync server which then resolves them using the DNS protocol. When
783393527e6a36415efb92e94a148c96b539e582vboxsync the DNS lookup completes, <span><strong class="command">lwresd</strong></span> encodes
783393527e6a36415efb92e94a148c96b539e582vboxsync the answers in the lightweight resolver format and returns
783393527e6a36415efb92e94a148c96b539e582vboxsync them to the client that made the request.
783393527e6a36415efb92e94a148c96b539e582vboxsync If <code class="filename">/etc/resolv.conf</code> contains any
783393527e6a36415efb92e94a148c96b539e582vboxsync <code class="option">nameserver</code> entries, <span><strong class="command">lwresd</strong></span>
783393527e6a36415efb92e94a148c96b539e582vboxsync sends recursive DNS queries to those servers. This is similar
783393527e6a36415efb92e94a148c96b539e582vboxsync to the use of forwarders in a caching name server. If no
783393527e6a36415efb92e94a148c96b539e582vboxsync <code class="option">nameserver</code> entries are present, or if
783393527e6a36415efb92e94a148c96b539e582vboxsync forwarding fails, <span><strong class="command">lwresd</strong></span> resolves the
783393527e6a36415efb92e94a148c96b539e582vboxsync queries autonomously starting at the root name servers, using
783393527e6a36415efb92e94a148c96b539e582vboxsync a built-in list of root server hints.
783393527e6a36415efb92e94a148c96b539e582vboxsync Use IPv4 only even if the host machine is capable of IPv6.
783393527e6a36415efb92e94a148c96b539e582vboxsync <code class="option">-4</code> and <code class="option">-6</code> are mutually
783393527e6a36415efb92e94a148c96b539e582vboxsync Use IPv6 only even if the host machine is capable of IPv4.
783393527e6a36415efb92e94a148c96b539e582vboxsync <code class="option">-4</code> and <code class="option">-6</code> are mutually
783393527e6a36415efb92e94a148c96b539e582vboxsync<dt><span class="term">-c <em class="replaceable"><code>config-file</code></em></span></dt>
783393527e6a36415efb92e94a148c96b539e582vboxsync Use <em class="replaceable"><code>config-file</code></em> as the
783393527e6a36415efb92e94a148c96b539e582vboxsync configuration file instead of the default,
783393527e6a36415efb92e94a148c96b539e582vboxsync <code class="option">-c</code> can not be used with <code class="option">-C</code>.
783393527e6a36415efb92e94a148c96b539e582vboxsync<dt><span class="term">-C <em class="replaceable"><code>config-file</code></em></span></dt>
783393527e6a36415efb92e94a148c96b539e582vboxsync Use <em class="replaceable"><code>config-file</code></em> as the
783393527e6a36415efb92e94a148c96b539e582vboxsync configuration file instead of the default,
783393527e6a36415efb92e94a148c96b539e582vboxsync <code class="option">-C</code> can not be used with <code class="option">-c</code>.
783393527e6a36415efb92e94a148c96b539e582vboxsync<dt><span class="term">-d <em class="replaceable"><code>debug-level</code></em></span></dt>
783393527e6a36415efb92e94a148c96b539e582vboxsync Set the daemon's debug level to <em class="replaceable"><code>debug-level</code></em>.
783393527e6a36415efb92e94a148c96b539e582vboxsync Debugging traces from <span><strong class="command">lwresd</strong></span> become
783393527e6a36415efb92e94a148c96b539e582vboxsync more verbose as the debug level increases.
783393527e6a36415efb92e94a148c96b539e582vboxsync Run the server in the foreground (i.e. do not daemonize).
783393527e6a36415efb92e94a148c96b539e582vboxsync Run the server in the foreground and force all logging
783393527e6a36415efb92e94a148c96b539e582vboxsync<dt><span class="term">-i <em class="replaceable"><code>pid-file</code></em></span></dt>
783393527e6a36415efb92e94a148c96b539e582vboxsync Use <em class="replaceable"><code>pid-file</code></em> as the
783393527e6a36415efb92e94a148c96b539e582vboxsync PID file instead of the default,
783393527e6a36415efb92e94a148c96b539e582vboxsync <code class="filename">/var/run/lwresd/lwresd.pid</code>.
783393527e6a36415efb92e94a148c96b539e582vboxsync<dt><span class="term">-m <em class="replaceable"><code>flag</code></em></span></dt>
783393527e6a36415efb92e94a148c96b539e582vboxsync Turn on memory usage debugging flags. Possible flags are
783393527e6a36415efb92e94a148c96b539e582vboxsync <em class="replaceable"><code>size</code></em>, and
783393527e6a36415efb92e94a148c96b539e582vboxsync These correspond to the ISC_MEM_DEBUGXXXX flags described in
783393527e6a36415efb92e94a148c96b539e582vboxsync<dt><span class="term">-n <em class="replaceable"><code>#cpus</code></em></span></dt>
783393527e6a36415efb92e94a148c96b539e582vboxsync Create <em class="replaceable"><code>#cpus</code></em> worker threads
783393527e6a36415efb92e94a148c96b539e582vboxsync to take advantage of multiple CPUs. If not specified,
783393527e6a36415efb92e94a148c96b539e582vboxsync <span><strong class="command">lwresd</strong></span> will try to determine the
783393527e6a36415efb92e94a148c96b539e582vboxsync number of CPUs present and create one thread per CPU.
783393527e6a36415efb92e94a148c96b539e582vboxsync If it is unable to determine the number of CPUs, a
783393527e6a36415efb92e94a148c96b539e582vboxsync single worker thread will be created.
783393527e6a36415efb92e94a148c96b539e582vboxsync<dt><span class="term">-P <em class="replaceable"><code>port</code></em></span></dt>
783393527e6a36415efb92e94a148c96b539e582vboxsync Listen for lightweight resolver queries on port
783393527e6a36415efb92e94a148c96b539e582vboxsync not specified, the default is port 921.
783393527e6a36415efb92e94a148c96b539e582vboxsync<dt><span class="term">-p <em class="replaceable"><code>port</code></em></span></dt>
0bfb99a63b33971b6285648db35f5562705966d9vboxsync Send DNS lookups to port <em class="replaceable"><code>port</code></em>. If not
783393527e6a36415efb92e94a148c96b539e582vboxsync specified, the default is port 53. This provides a
783393527e6a36415efb92e94a148c96b539e582vboxsync way of testing the lightweight resolver daemon with a
783393527e6a36415efb92e94a148c96b539e582vboxsync name server that listens for queries on a non-standard
783393527e6a36415efb92e94a148c96b539e582vboxsync port number.
783393527e6a36415efb92e94a148c96b539e582vboxsync Write memory usage statistics to <code class="filename">stdout</code>
783393527e6a36415efb92e94a148c96b539e582vboxsync<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
783393527e6a36415efb92e94a148c96b539e582vboxsync This option is mainly of interest to BIND 9 developers
783393527e6a36415efb92e94a148c96b539e582vboxsync and may be removed or changed in a future release.
783393527e6a36415efb92e94a148c96b539e582vboxsync<dt><span class="term">-t <em class="replaceable"><code>directory</code></em></span></dt>
783393527e6a36415efb92e94a148c96b539e582vboxsync to <em class="replaceable"><code>directory</code></em> after
783393527e6a36415efb92e94a148c96b539e582vboxsync processing the command line arguments, but before
783393527e6a36415efb92e94a148c96b539e582vboxsync reading the configuration file.
783393527e6a36415efb92e94a148c96b539e582vboxsync<div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;">
783393527e6a36415efb92e94a148c96b539e582vboxsync This option should be used in conjunction with the
0bfb99a63b33971b6285648db35f5562705966d9vboxsync <code class="option">-u</code> option, as chrooting a process
783393527e6a36415efb92e94a148c96b539e582vboxsync running as root doesn't enhance security on most
783393527e6a36415efb92e94a148c96b539e582vboxsync systems; the way <code class="function">chroot(2)</code> is
783393527e6a36415efb92e94a148c96b539e582vboxsync defined allows a process with root privileges to
783393527e6a36415efb92e94a148c96b539e582vboxsync escape a chroot jail.
783393527e6a36415efb92e94a148c96b539e582vboxsync<dt><span class="term">-u <em class="replaceable"><code>user</code></em></span></dt>
783393527e6a36415efb92e94a148c96b539e582vboxsync to <em class="replaceable"><code>user</code></em> after completing
783393527e6a36415efb92e94a148c96b539e582vboxsync privileged operations, such as creating sockets that
783393527e6a36415efb92e94a148c96b539e582vboxsync listen on privileged ports.
783393527e6a36415efb92e94a148c96b539e582vboxsync Report the version number and exit.
783393527e6a36415efb92e94a148c96b539e582vboxsync<dt><span class="term"><code class="filename">/etc/resolv.conf</code></span></dt>
783393527e6a36415efb92e94a148c96b539e582vboxsync The default configuration file.
783393527e6a36415efb92e94a148c96b539e582vboxsync<dt><span class="term"><code class="filename">/var/run/lwresd.pid</code></span></dt>
783393527e6a36415efb92e94a148c96b539e582vboxsync The default process-id file.
783393527e6a36415efb92e94a148c96b539e582vboxsync<p><span class="citerefentry"><span class="refentrytitle">named</span>(8)</span>,
783393527e6a36415efb92e94a148c96b539e582vboxsync <span class="citerefentry"><span class="refentrytitle">lwres</span>(3)</span>,
783393527e6a36415efb92e94a148c96b539e582vboxsync <span class="citerefentry"><span class="refentrytitle">resolver</span>(5)</span>.
783393527e6a36415efb92e94a148c96b539e582vboxsync<p><span class="corpauthor">Internet Systems Consortium</span>