summaryrefslogtreecommitdiff
path: root/man/systemd-resolve.xml
blob: 0defa2d7fbbb1b62dc90ebbab3e1a5cd39aadb22 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
<?xml version='1.0'?>
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">

<!--
  This file is part of systemd.

  Copyright 2016 Lennart Poettering

  systemd is free software; you can redistribute it and/or modify it
  under the terms of the GNU Lesser General Public License as published by
  the Free Software Foundation; either version 2.1 of the License, or
  (at your option) any later version.

  systemd is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public License
  along with systemd; If not, see <http://www.gnu.org/licenses/>.
-->

<refentry id="systemd-resolve"
          xmlns:xi="http://www.w3.org/2001/XInclude">

  <refentryinfo>
    <title>systemd-resolve</title>
    <productname>systemd</productname>

    <authorgroup>
      <author>
        <contrib>Developer</contrib>
        <firstname>Lennart</firstname>
        <surname>Poettering</surname>
        <email>lennart@poettering.net</email>
      </author>
    </authorgroup>
  </refentryinfo>

  <refmeta>
    <refentrytitle>systemd-resolve</refentrytitle>
    <manvolnum>1</manvolnum>
  </refmeta>

  <refnamediv>
    <refname>systemd-resolve</refname>
    <refpurpose>Resolve domain names, IPV4 and IPv6 addresses, DNS resource records, and services</refpurpose>
  </refnamediv>

  <refsynopsisdiv>
    <cmdsynopsis>
      <command>systemd-resolve</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <arg choice="plain" rep="repeat"><replaceable>HOSTNAME</replaceable></arg>
    </cmdsynopsis>

    <cmdsynopsis>
      <command>systemd-resolve</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <arg choice="plain" rep="repeat"><replaceable>ADDRESS</replaceable></arg>
    </cmdsynopsis>

    <cmdsynopsis>
      <command>systemd-resolve</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <command> --type=<replaceable>TYPE</replaceable></command>
      <arg choice="plain" rep="repeat"><replaceable>RRDOMAIN</replaceable></arg>
    </cmdsynopsis>

    <cmdsynopsis>
      <command>systemd-resolve</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <command> --service</command>
      <arg choice="plain"><arg choice="opt"><arg choice="opt"><replaceable>NAME</replaceable></arg>
      <replaceable>TYPE</replaceable></arg> <replaceable>DOMAIN</replaceable></arg>
    </cmdsynopsis>

    <cmdsynopsis>
      <command>systemd-resolve</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <command> --openpgp</command>
      <arg choice="plain"><replaceable>USER@DOMAIN</replaceable></arg>
    </cmdsynopsis>

    <cmdsynopsis>
      <command>systemd-resolve</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <command> --statistics</command>
    </cmdsynopsis>

    <cmdsynopsis>
      <command>systemd-resolve</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <command> --reset-statistics</command>
    </cmdsynopsis>

  </refsynopsisdiv>

  <refsect1>
    <title>Description</title>

    <para><command>systemd-resolve</command> may be used to resolve domain names, IPv4 and IPv6 addresses, DNS resource
    records and services with the
    <citerefentry><refentrytitle>systemd-resolved.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
    resolver service. By default, the specified list of parameters will be resolved as hostnames, retrieving their IPv4
    and IPv6 addresses. If the parameters specified are formatted as IPv4 or IPv6 operation the reverse operation is
    done, and a hostname is retrieved for the specified addresses.</para>

    <para>The <option>--type=</option> switch may be used to specify a DNS resource record type (A, AAAA, SOA, MX, ...) in
    order to request a specific DNS resource record, instead of the address or reverse address lookups.
    The special value <literal>help</literal> may be used to list known values.</para>

    <para>The <option>--service</option> switch may be used to resolve <ulink
    url="https://tools.ietf.org/html/rfc2782">SRV</ulink> and <ulink
    url="https://tools.ietf.org/html/rfc6763">DNS-SD</ulink> services (see below). In this mode, between one and three
    arguments are required. If three parameters are passed the first is assumed to be the DNS-SD service name, the
    second the SRV service type, and the third the domain to search in. In this case a full DNS-SD style SRV and TXT
    lookup is executed. If only two parameters are specified, the first is assumed to be the SRV service type, and the
    second the domain to look in. In this case no TXT RR is requested. Finally, if only one parameter is specified, it
    is assumed to be a domain name, that is already prefixed with an SRV type, and an SRV lookup is done (no
    TXT).</para>

    <para>The <option>--openpgp</option> switch may be use to query PGP keys stored as the
    <ulink url="https://tools.ietf.org/html/draft-wouters-dane-openpgp-02">OPENPGPKEY</ulink> resource records.
    When this option is specified one or more e-mail address must be specified.</para>

    <para>The <option>--statistics</option> switch may be used to show resolver statistics, including information about
    the number of succesful and failed DNSSEC validations.</para>

    <para>The <option>--reset-statistics</option> may be used to reset various statistics counters maintained the
    resolver, including those shown in the <option>--statistics</option> output. This operation requires root
    privileges.</para>
  </refsect1>

  <refsect1>
    <title>Options</title>
    <variablelist>
      <varlistentry>
        <term><option>-4</option></term>
        <term><option>-6</option></term>

        <listitem><para>By default, when resolving a hostname, both IPv4 and IPv6
        addresses are acquired. By specifying <option>-4</option> only IPv4 addresses are requested, by specifying
        <option>-6</option> only IPv6 addresses are requested.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term><option>-i</option> <replaceable>INTERFACE</replaceable></term>
        <term><option>--interface=</option><replaceable>INTERFACE</replaceable></term>

        <listitem><para>Specifies the network interface to execute the query on. This may either be specified as numeric
        interface index or as network interface string (e.g. <literal>en0</literal>). Note that this option has no
        effect if system-wide DNS configuration (as configured in <filename>/etc/resolv.conf</filename> or
        <filename>/etc/systemd/resolve.conf</filename>) in place of per-link configuration is used.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>-p</option> <replaceable>PROTOCOL</replaceable></term>
        <term><option>--protocol=</option><replaceable>PROTOCOL</replaceable></term>

        <listitem><para>Specifies the network protocol for the query. May be one of <literal>dns</literal>
        (i.e. classic unicast DNS), <literal>llmnr</literal> (<ulink
        url="https://tools.ietf.org/html/rfc4795">Link-Local Multicast Name Resolution</ulink>),
        <literal>llmr-ipv4</literal>, <literal>llmnr-ipv6</literal> (LLMNR via the indicated underlying IP
        protocols). By default the lookup is done via all protocols suitable for the lookup. If used, limits the set of
        protocols that may be used. Use this option multiple times to enable resolving via multiple protocols at the
        same time. The setting <literal>llmnr</literal> is identical to specifying this switch once with
        <literal>llmnr-ipv4</literal> and once via <literal>llmnr-ipv6</literal>. Note that this option does not force
        the service to resolve the operation with the specified protocol, as that might require a suitable network
        interface and configuration.
        The special value <literal>help</literal> may be used to list known values.
        </para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>-t</option> <replaceable>TYPE</replaceable></term>
        <term><option>--type=</option><replaceable>TYPE</replaceable></term>
        <term><option>-c</option> <replaceable>CLASS</replaceable></term>
        <term><option>--class=</option><replaceable>CLASS</replaceable></term>

        <listitem><para>Specifies the DNS resource record type (e.g. A, AAAA, MX, …) and class (e.g. IN, ANY, …) to
        look up. If these options are used a DNS resource record set matching the specified class and type is
        requested. The class defaults to IN if only a type is specified.
        The special value <literal>help</literal> may be used to list known values.
        </para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--service</option></term>

        <listitem><para>Enables service resolution. This enables DNS-SD and simple SRV service resolution, depending
        on the specified list of parameters (see above).</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--service-address=</option><replaceable>BOOL</replaceable></term>

        <listitem><para>Takes a boolean parameter. If true (the default), when doing a service lookup with
        <option>--service</option> the hostnames contained in the SRV resource records are resolved as well.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--service-txt=</option><replaceable>BOOL</replaceable></term>

        <listitem><para>Takes a boolean parameter. If true (the default), when doing a DNS-SD service lookup with
        <option>--service</option> the TXT service metadata record is resolved as well.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--openpgp</option></term>

        <listitem><para>Enables OPENPGPKEY resource record resolution (see above). Specified e-mail
        addresses are converted to the corresponding DNS domain name, and any OPENPGPKEY keys are
        printed.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--cname=</option><replaceable>BOOL</replaceable></term>

        <listitem><para>Takes a boolean parameter. If true (the default), DNS CNAME or DNAME redirections are
        followed. Otherwise, if a CNAME or DNAME record is encountered while resolving, an error is
        returned.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--search=</option><replaceable>BOOL</replaceable></term>

        <listitem><para>Takes a boolean parameter. If true (the default), any specified single-label hostnames will be
        searched in the domains configured in the search domain list, if it is non-empty. Otherwise, the search domain
        logic is disabled.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--legend=</option><replaceable>BOOL</replaceable></term>

        <listitem><para>Takes a boolean parameter. If true (the default), column headers and meta information about the
        query response are shown. Otherwise, this output is suppressed.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--statistics</option></term>

        <listitem><para>If specified general resolver statistics are shown, including information whether DNSSEC is
        enabled and available, as well as resolution and validation statistics.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--reset-statistics</option></term>

        <listitem><para>Resets the statistics counters shown in <option>--statistics</option> to zero.</para></listitem>
      </varlistentry>

      <xi:include href="standard-options.xml" xpointer="help" />
      <xi:include href="standard-options.xml" xpointer="version" />
    </variablelist>
  </refsect1>

  <refsect1>
    <title>Examples</title>

    <example>
      <title>Retrieve the addresses of the <literal>www.0pointer.net</literal> domain</title>

      <programlisting>$ systemd-resolve www.0pointer.net</programlisting>
    </example>

    <example>
      <title>Retrieve the domain of the <literal>85.214.157.71</literal> IP address</title>

      <programlisting>$ systemd-resolve 85.214.157.71</programlisting>
    </example>

    <example>
      <title>Retrieve the MX record of the <literal>0pointer.net</literal> domain</title>

      <programlisting>$ systemd-resolve -t MX 0pointer.net</programlisting>
    </example>

    <example>
      <title>Resolve an SRV service</title>

      <programlisting>$ systemd-resolve --service _xmpp-server._tcp gmail.com</programlisting>
    </example>

  </refsect1>

  <refsect1>
    <title>See Also</title>
    <para>
      <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
      <citerefentry><refentrytitle>systemd-resolved.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
    </para>
  </refsect1>
</refentry>