diff options
Diffstat (limited to '')
| -rw-r--r-- | doc/arm/Bv9ARM.ch05.html | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/doc/arm/Bv9ARM.ch05.html b/doc/arm/Bv9ARM.ch05.html new file mode 100644 index 0000000..aa2b8d7 --- /dev/null +++ b/doc/arm/Bv9ARM.ch05.html @@ -0,0 +1,147 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<!-- + - Copyright (C) 2000-2019 Internet Systems Consortium, Inc. ("ISC") + - + - This Source Code Form is subject to the terms of the Mozilla Public + - License, v. 2.0. If a copy of the MPL was not distributed with this + - file, You can obtain one at http://mozilla.org/MPL/2.0/. +--> +<html lang="en"> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> +<title>Chapter 5. The BIND 9 Lightweight Resolver</title> +<meta name="generator" content="DocBook XSL Stylesheets V1.78.1"> +<link rel="home" href="Bv9ARM.html" title="BIND 9 Administrator Reference Manual"> +<link rel="up" href="Bv9ARM.html" title="BIND 9 Administrator Reference Manual"> +<link rel="prev" href="Bv9ARM.ch04.html" title="Chapter 4. Advanced DNS Features"> +<link rel="next" href="Bv9ARM.ch06.html" title="Chapter 6. BIND 9 Configuration Reference"> +</head> +<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> +<div class="navheader"> +<table width="100%" summary="Navigation header"> +<tr><th colspan="3" align="center">Chapter 5. The <acronym class="acronym">BIND</acronym> 9 Lightweight Resolver</th></tr> +<tr> +<td width="20%" align="left"> +<a accesskey="p" href="Bv9ARM.ch04.html">Prev</a> </td> +<th width="60%" align="center"> </th> +<td width="20%" align="right"> <a accesskey="n" href="Bv9ARM.ch06.html">Next</a> +</td> +</tr> +</table> +<hr> +</div> +<div class="chapter"> +<div class="titlepage"><div><div><h1 class="title"> +<a name="Bv9ARM.ch05"></a>Chapter 5. The <acronym class="acronym">BIND</acronym> 9 Lightweight Resolver</h1></div></div></div> +<div class="toc"> +<p><b>Table of Contents</b></p> +<dl class="toc"> +<dt><span class="section"><a href="Bv9ARM.ch05.html#lightweight_resolver">The Lightweight Resolver Library</a></span></dt> +<dt><span class="section"><a href="Bv9ARM.ch05.html#lwresd">Running a Resolver Daemon</a></span></dt> +</dl> +</div> + + <div class="section"> +<div class="titlepage"><div><div><h2 class="title" style="clear: both"> +<a name="lightweight_resolver"></a>The Lightweight Resolver Library</h2></div></div></div> + + <p> + Traditionally applications have been linked with a stub resolver + library that sends recursive DNS queries to a local caching name + server. + </p> + <p> + IPv6 once introduced new complexity into the resolution process, + such as following A6 chains and DNAME records, and simultaneous + lookup of IPv4 and IPv6 addresses. Though most of the complexity was + then removed, these are hard or impossible + to implement in a traditional stub resolver. + </p> + <p> + <acronym class="acronym">BIND</acronym> 9 therefore can also provide resolution + services to local clients + using a combination of a lightweight resolver library and a resolver + daemon process running on the local host. These communicate using + a simple UDP-based protocol, the "lightweight resolver protocol" + that is distinct from and simpler than the full DNS protocol. + </p> + </div> + <div class="section"> +<div class="titlepage"><div><div><h2 class="title" style="clear: both"> +<a name="lwresd"></a>Running a Resolver Daemon</h2></div></div></div> + + <p> + To use the lightweight resolver interface, the system must + run the resolver daemon <span class="command"><strong>lwresd</strong></span> or a + local + name server configured with a <span class="command"><strong>lwres</strong></span> + statement. + </p> + + <p> + By default, applications using the lightweight resolver library will + make + UDP requests to the IPv4 loopback address (127.0.0.1) on port 921. + The + address can be overridden by <span class="command"><strong>lwserver</strong></span> + lines in + <code class="filename">/etc/resolv.conf</code>. + </p> + + <p> + The daemon currently only looks in the DNS, but in the future + it may use other sources such as <code class="filename">/etc/hosts</code>, + NIS, etc. + </p> + + <p> + The <span class="command"><strong>lwresd</strong></span> daemon is essentially a + caching-only name server that responds to requests using the + lightweight + resolver protocol rather than the DNS protocol. Because it needs + to run on each host, it is designed to require no or minimal + configuration. + Unless configured otherwise, it uses the name servers listed on + <span class="command"><strong>nameserver</strong></span> lines in <code class="filename">/etc/resolv.conf</code> + as forwarders, but is also capable of doing the resolution + autonomously if + none are specified. + </p> + <p> + The <span class="command"><strong>lwresd</strong></span> daemon may also be + configured with a + <code class="filename">named.conf</code> style configuration file, + in + <code class="filename">/etc/lwresd.conf</code> by default. A name + server may also + be configured to act as a lightweight resolver daemon using the + <span class="command"><strong>lwres</strong></span> statement in <code class="filename">named.conf</code>. + </p> + <p> + The number of client queries that the <span class="command"><strong>lwresd</strong></span> + daemon is able to serve can be set using the + <code class="option">lwres-tasks</code> and <code class="option">lwres-clients</code> + statements in the configuration. + </p> + </div> + </div> +<div class="navfooter"> +<hr> +<table width="100%" summary="Navigation footer"> +<tr> +<td width="40%" align="left"> +<a accesskey="p" href="Bv9ARM.ch04.html">Prev</a> </td> +<td width="20%" align="center"> </td> +<td width="40%" align="right"> <a accesskey="n" href="Bv9ARM.ch06.html">Next</a> +</td> +</tr> +<tr> +<td width="40%" align="left" valign="top">Chapter 4. Advanced DNS Features </td> +<td width="20%" align="center"><a accesskey="h" href="Bv9ARM.html">Home</a></td> +<td width="40%" align="right" valign="top"> Chapter 6. <acronym class="acronym">BIND</acronym> 9 Configuration Reference</td> +</tr> +</table> +</div> +<p xmlns:db="http://docbook.org/ns/docbook" style="text-align: center;">BIND 9.11.5-P4 (Extended Support Version)</p> +</body> +</html> |