delv.html revision 79f0eedd657d75889009226aa7ce23eeac28df5c
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt - Copyright (C) 2014, 2015 Internet Systems Consortium, Inc. ("ISC")
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt - Permission to use, copy, modify, and/or distribute this software for any
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt - purpose with or without fee is hereby granted, provided that the above
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt - copyright notice and this permission notice appear in all copies.
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt - THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt - REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt - AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt - INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt - LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt - OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt - PERFORMANCE OF THIS SOFTWARE.
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt<meta name="generator" content="DocBook XSL Stylesheets V1.78.1">
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="refentry">
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt<a name="man.delv"></a><div class="titlepage"></div>
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt<p>delv — DNS lookup and validation utility</p>
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt<div class="cmdsynopsis"><p><code class="command">delv</code> [@server] [<code class="option">-4</code>] [<code class="option">-6</code>] [<code class="option">-a <em class="replaceable"><code>anchor-file</code></em></code>] [<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">-d <em class="replaceable"><code>level</code></em></code>] [<code class="option">-i</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>] [name] [type] [class] [queryopt...]</p></div>
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt<div class="cmdsynopsis"><p><code class="command">delv</code> [<code class="option">-h</code>]</p></div>
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt<div class="cmdsynopsis"><p><code class="command">delv</code> [<code class="option">-v</code>]</p></div>
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt<div class="cmdsynopsis"><p><code class="command">delv</code> [queryopt...] [query...]</p></div>
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt<p><span class="command"><strong>delv</strong></span>
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt (Domain Entity Lookup & Validation) is a tool for sending
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt DNS queries and validating the results, using the same internal
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt resolver and validator logic as <span class="command"><strong>named</strong></span>.
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt <span class="command"><strong>delv</strong></span> will send to a specified name server all
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt queries needed to fetch and validate the requested data; this
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt includes the original requested query, subsequent queries to follow
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt CNAME or DNAME chains, and queries for DNSKEY, DS and DLV records
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt to establish a chain of trust for DNSSEC validation.
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt It does not perform iterative resolution, but simulates the
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt behavior of a name server configured for DNSSEC validating and
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt By default, responses are validated using built-in DNSSEC trust
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt anchors for the root zone (".") and for the ISC DNSSEC lookaside
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt validation zone ("dlv.isc.org"). Records returned by
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt <span class="command"><strong>delv</strong></span> are either fully validated or
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt were not signed. If validation fails, an explanation of
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt the failure is included in the output; the validation process
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt can be traced in detail. Because <span class="command"><strong>delv</strong></span> does
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt not rely on an external server to carry out validation, it can
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt be used to check the validity of DNS responses in environments
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt where local name servers may not be trustworthy.
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt Unless it is told to query a specific name server,
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt <span class="command"><strong>delv</strong></span> will try each of the servers listed in
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt <code class="filename">/etc/resolv.conf</code>. If no usable server
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt addresses are found, <span class="command"><strong>delv</strong></span> will send
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt queries to the localhost addresses (127.0.0.1 for IPv4, ::1
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt When no command line arguments or options are given,
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt <span class="command"><strong>delv</strong></span> will perform an NS query for "."
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt (the root zone).
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt A typical invocation of <span class="command"><strong>delv</strong></span> looks like:
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt<pre class="programlisting"> delv @server name type </pre>
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt<div class="variablelist"><dl class="variablelist">
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt<dt><span class="term"><code class="constant">server</code></span></dt>
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt is the name or IP address of the name server to query. This
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt can be an IPv4 address in dotted-decimal notation or an IPv6
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt address in colon-delimited notation. When the supplied
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt <em class="parameter"><code>server</code></em> argument is a hostname,
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt <span class="command"><strong>delv</strong></span> resolves that name before
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt querying that name server (note, however, that this
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt initial lookup is <span class="emphasis"><em>not</em></span> validated
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt If no <em class="parameter"><code>server</code></em> argument is
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt provided, <span class="command"><strong>delv</strong></span> consults
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt <code class="filename">/etc/resolv.conf</code>; if an
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt address is found there, it queries the name server at
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt that address. If either of the <code class="option">-4</code> or
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt <code class="option">-6</code> options are in use, then
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt only addresses for the corresponding transport
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt will be tried. If no usable addresses are found,
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt <span class="command"><strong>delv</strong></span> will send queries to
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt the localhost addresses (127.0.0.1 for IPv4,
b66b333f59cf51ef87f973084a5023acd9317fb2Evan Hunt ::1 for IPv6).
14a656f94b1fd0ababd84a772228dfa52276ba15Evan Hunt<dt><span class="term"><code class="constant">name</code></span></dt>
DNSSEC lookaside validation zone ("dlv.isc.org").
using nibble format under the IP6.ARPA domain.
e.g. "[ key id = value ]".
a trust anchor of "dlv.isc.org", for which there is a