summaryrefslogtreecommitdiff
path: root/man/systemd-resolve.xml
blob: 21d2901203ed4ed8ecb2d9705e7b4f73e46ec3df (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
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
<?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">

<!--
  SPDX-License-Identifier: LGPL-2.1+

  This file is part of systemd.

  Copyright 2016 Lennart Poettering
-->

<refentry id="systemd-resolve" conditional='ENABLE_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>
    <refname>resolvconf</refname>
    <refpurpose>Resolve domain names, IPV4 and IPv6 addresses, DNS resource records, and services; introspect and reconfigure the DNS resolver</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>DOMAIN</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> --tlsa</command>
      <arg choice="plain"><replaceable>DOMAIN<optional>:PORT</optional></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>

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

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

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

    <cmdsynopsis>
      <command>systemd-resolve</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <command> --set-dns=<replaceable>SERVER</replaceable></command> <command> --set-domain=<replaceable>DOMAIN</replaceable> --set-llmnr=<replaceable>MODE</replaceable> --set-mdns=<replaceable>MODE</replaceable> --set-dnssec=<replaceable>MODE</replaceable> --set-nta=<replaceable>DOMAIN</replaceable></command>
    </cmdsynopsis>

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

    <cmdsynopsis>
      <command>resolvconf</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <command> -a <replaceable>INTERFACE</replaceable> &lt; <replaceable>FILE</replaceable></command>
    </cmdsynopsis>

    <cmdsynopsis>
      <command>resolvconf</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <command> -d <replaceable>INTERFACE</replaceable></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 program's output contains information about the protocol used for the look-up and on which network
    interface the data was discovered. It also contains information on whether the information could be
    authenticated. All data for which local DNSSEC validation succeeds is considered authenticated. Moreover all data
    originating from local, trusted sources is also reported authenticated, including resolution of the local host
    name, the <literal>localhost</literal> host name or all data from <filename>/etc/hosts</filename>.</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 used to query PGP keys stored as
    <ulink url="https://tools.ietf.org/html/rfc7929">OPENPGPKEY</ulink> resource records.
    When this option is specified one or more e-mail address must be specified.</para>

    <para>The <option>--tlsa</option> switch maybe be used to query TLS public
    keys stored as
    <ulink url="https://tools.ietf.org/html/rfc6698">TLSA</ulink> resource records.
    When this option is specified one or more domain names must be specified.</para>

    <para>The <option>--statistics</option> switch may be used to show resolver statistics, including information about
    the number of successful 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>llmnr-ipv4</literal>, <literal>llmnr-ipv6</literal> (LLMNR via the indicated underlying IP
        protocols), <literal>mdns</literal> (<ulink url="https://www.ietf.org/rfc/rfc6762.txt">Multicast DNS</ulink>),
        <literal>mdns-ipv4</literal>, <literal>mdns-ipv6</literal> (MDNS 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>--tlsa</option></term>

        <listitem><para>Enables TLSA resource record resolution (see above).
        A query will be performed for each of the specified names prefixed with
        the port and family
        (<literal>_<replaceable>port</replaceable>._<replaceable>family</replaceable>.<replaceable>domain</replaceable></literal>).
        The port number may be specified after a colon
        (<literal>:</literal>), otherwise <constant>443</constant> will be used
        by default. The family may be specified as an argument after
        <option>--tlsa</option>, otherwise <constant>tcp</constant> will be
        used.</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>--raw</option><optional>=payload|packet</optional></term>

        <listitem><para>Dump the answer as binary data. If there is no argument or if the argument is
        <literal>payload</literal>, the payload of the packet is exported. If the argument is
        <literal>packet</literal>, the whole packet is dumped in wire format, prefixed by
        length specified as a little-endian 64-bit number. This format allows multiple packets
        to be dumped and unambiguously parsed.</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>

      <varlistentry>
        <term><option>--flush-caches</option></term>

        <listitem><para>Flushes all DNS resource record caches the service maintains locally. This is mostly equivalent
        to sending the <constant>SIGUSR2</constant> to the <command>systemd-resolved</command>
        service.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--reset-server-features</option></term>

        <listitem><para>Flushes all feature level information the resolver learnt about specific servers, and ensures
        that the server feature probing logic is started from the beginning with the next look-up request. This is
        mostly equivalent to sending the <constant>SIGRTMIN+1</constant> to the <command>systemd-resolved</command>
        service.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--status</option></term>

        <listitem><para>Shows the global and per-link DNS settings in currently in effect.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--set-dns=SERVER</option></term>
        <term><option>--set-domain=DOMAIN</option></term>
        <term><option>--set-llmnr=MODE</option></term>
        <term><option>--set-mdns=MODE</option></term>
        <term><option>--set-dnssec=MODE</option></term>
        <term><option>--set-nta=DOMAIN</option></term>

        <listitem><para>Set per-interface DNS configuration. These switches may be used to configure various DNS
        settings for network interfaces that aren't managed by
        <citerefentry><refentrytitle>systemd-networkd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>. (These
        commands will fail when used on interfaces that are managed by <command>systemd-networkd</command>, please
        configure their DNS settings directly inside the <filename>.network</filename> files instead.) These switches
        may be used to inform <command>systemd-resolved</command> about per-interface DNS configuration determined
        through external means. Multiple of these switches may be passed on a single invocation of
        <command>systemd-resolve</command> in order to set multiple configuration options at once. If any of these
        switches is used, it must be combined with <option>--interface=</option> to indicate the network interface the
        new DNS configuration belongs to. The <option>--set-dns=</option> option expects an IPv4 or IPv6 address
        specification of a DNS server to use, and may be used multiple times to define multiple servers for the same
        interface. The <option>--set-domain=</option> option expects a valid DNS domain, possibly prefixed with
        <literal>~</literal>, and configures a per-interface search or route-only domain. It may be used multiple times
        to configure multiple such domains. The <option>--set-llmnr=</option>, <option>--set-mdns=</option> and
        <option>--set-dnssec=</option> options may be used to configure the per-interface LLMNR, MulticastDNS and
        DNSSEC settings. Finally, <option>--set-nta=</option> may be used to configure additional per-interface DNSSEC
        NTA domains and may also be used multiple times. For details about these settings, their possible values and
        their effect, see the corresponding options in
        <citerefentry><refentrytitle>systemd.network</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--revert</option></term>

        <listitem><para>Revert the per-interface DNS configuration. This option must be combined with
        <option>--interface=</option> to indicate the network interface the DNS configuration shall be reverted on. If
        the DNS configuration is reverted all per-interface DNS setting are reset to their defaults, undoing all
        effects of <option>--set-dns=</option>, <option>--set-domain=</option>, <option>--set-llmnr=</option>,
        <option>--set-mdns=</option>, <option>--set-dnssec=</option>, <option>--set-nta=</option>. Note that when a
        network interface disappears all configuration is lost automatically, an explicit reverting is not necessary in
        that case.</para></listitem>
      </varlistentry>

      <xi:include href="standard-options.xml" xpointer="help" />
      <xi:include href="standard-options.xml" xpointer="version" />
      <xi:include href="standard-options.xml" xpointer="no-pager" />
    </variablelist>
  </refsect1>

  <refsect1>
    <title>Compatibility with <citerefentry><refentrytitle>resolvconf</refentrytitle><manvolnum>8</manvolnum></citerefentry></title>

    <para><command>systemd-resolve</command> is a multi-call binary. When invoked as <literal>resolvconf</literal>
    (generally achieved by means of a symbolic link of this name to the <command>systemd-resolve</command> binary) it
    is run in a limited <citerefentry><refentrytitle>resolvconf</refentrytitle><manvolnum>8</manvolnum></citerefentry>
    compatibility mode. It accepts mostly the same arguments and pushes all data into
    <citerefentry><refentrytitle>systemd-resolved.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
    similar to how <option>--set-dns=</option> and <option>--set-domain=</option> operate. Note that
    <command>systemd-resolved.service</command> is the only supported backend, which is different from other
    implementations of this command. Note that not all operations supported by other implementations are supported
    natively. Specifically:</para>

    <variablelist>
      <varlistentry>
        <term><option>-a</option></term>
        <listitem><para>Registers per-interface DNS configuration data with
        <command>systemd-resolved</command>. Expects a network interface name as only command line argument. Reads
        <citerefentry><refentrytitle>resolv.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry> compatible DNS
        configuration data from its standard input. Relevant fields are <literal>nameserver</literal> and
        <literal>domain</literal>/<literal>search</literal>. This command is mostly identical to invoking
        <command>systemd-resolve</command> with a combination of <option>--set-dns=</option> and
        <option>--set-domain=</option>.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>-d</option></term>
        <listitem><para>Unregisters per-interface DNS configuration data with <command>systemd-resolved</command>. This
        command is mostly identical to invoking <command>systemd-resolve</command> with
        <option>--revert</option>.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>-f</option></term>

        <listitem><para>When specified <option>-a</option> and <option>-d</option> will not complain about missing
        network interfaces and will silently execute no operation in that case.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>-x</option></term>

        <listitem><para>This switch for "exclusive" operation is supported only partially. It is mapped to an
        additional configured search domain of <literal>~.</literal> — i.e. ensures that DNS traffic is preferably
        routed to the DNS servers on this interface, unless there are other, more specific domains configured on other
        interfaces.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>-m</option></term>
        <term><option>-p</option></term>

        <listitem><para>These switches are not supported and are silently ignored.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>-u</option></term>
        <term><option>-I</option></term>
        <term><option>-i</option></term>
        <term><option>-l</option></term>
        <term><option>-R</option></term>
        <term><option>-r</option></term>
        <term><option>-v</option></term>
        <term><option>-V</option></term>
        <term><option>--enable-updates</option></term>
        <term><option>--disable-updates</option></term>
        <term><option>--are-updates-enabled</option></term>

        <listitem><para>These switches are not supported and the command will fail if used.</para></listitem>
      </varlistentry>

    </variablelist>

    <para>See <citerefentry><refentrytitle>resolvconf</refentrytitle><manvolnum>8</manvolnum></citerefentry> for details on this command line options.</para>
  </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
www.0pointer.net: 2a01:238:43ed:c300:10c3:bcf3:3266:da74
                  85.214.157.71

-- Information acquired via protocol DNS in 611.6ms.
-- Data is authenticated: no
</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
85.214.157.71: gardel.0pointer.net

-- Information acquired via protocol DNS in 1.2997s.
-- Data is authenticated: no
</programlisting>
    </example>

    <example>
      <title>Retrieve the MX record of the <literal>yahoo.com</literal> domain</title>

      <programlisting>$ systemd-resolve -t MX yahoo.com --legend=no
yahoo.com. IN MX    1 mta7.am0.yahoodns.net
yahoo.com. IN MX    1 mta6.am0.yahoodns.net
yahoo.com. IN MX    1 mta5.am0.yahoodns.net
</programlisting>
    </example>

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

      <programlisting>$ systemd-resolve --service _xmpp-server._tcp gmail.com
_xmpp-server._tcp/gmail.com: alt1.xmpp-server.l.google.com:5269 [priority=20, weight=0]
                             173.194.210.125
                             alt4.xmpp-server.l.google.com:5269 [priority=20, weight=0]
                             173.194.65.125
                             …
</programlisting>
    </example>

    <example>
      <title>Retrieve a PGP key</title>

      <programlisting>$ systemd-resolve --openpgp zbyszek@fedoraproject.org
d08ee310438ca124a6149ea5cc21b6313b390dce485576eff96f8722._openpgpkey.fedoraproject.org. IN OPENPGPKEY
        mQINBFBHPMsBEACeInGYJCb+7TurKfb6wGyTottCDtiSJB310i37/6ZYoeIay/5soJjlMyf
        MFQ9T2XNT/0LM6gTa0MpC1st9LnzYTMsT6tzRly1D1UbVI6xw0g0vE5y2Cjk3xUwAynCsSs
        …
</programlisting>
    </example>

    <example>
      <title>Retrieve a TLS key (<literal>=tcp</literal> and
      <literal>:443</literal> could be skipped)</title>

      <programlisting>$ systemd-resolve --tlsa=tcp fedoraproject.org:443
_443._tcp.fedoraproject.org IN TLSA 0 0 1 19400be5b7a31fb733917700789d2f0a2471c0c9d506c0e504c06c16d7cb17c0
        -- Cert. usage: CA constraint
        -- Selector: Full Certificate
        -- Matching type: SHA-256
</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>,
      <citerefentry><refentrytitle>systemd.dnssd</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
      <citerefentry><refentrytitle>systemd-networkd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
      <citerefentry><refentrytitle>resolvconf</refentrytitle><manvolnum>8</manvolnum></citerefentry>
    </para>
  </refsect1>
</refentry>