chiark / gitweb /
484d6f31c78dc76b3c0103442215f69a05b0e0d8
[elogind.git] / man / systemd.network.xml
1 <?xml version='1.0'?> <!--*-nxml-*-->
2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
3         "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
4
5 <!--
6   This file is part of systemd.
7
8   Copyright 2013 Tom Gundersen
9
10   systemd is free software; you can redistribute it and/or modify it
11   under the terms of the GNU Lesser General Public License as published by
12   the Free Software Foundation; either version 2.1 of the License, or
13   (at your option) any later version.
14
15   systemd is distributed in the hope that it will be useful, but
16   WITHOUT ANY WARRANTY; without even the implied warranty of
17   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18   Lesser General Public License for more details.
19
20   You should have received a copy of the GNU Lesser General Public License
21   along with systemd; If not, see <http://www.gnu.org/licenses/>.
22 -->
23
24 <refentry id="systemd.network" conditional='ENABLE_NETWORKD'>
25
26         <refentryinfo>
27                 <title>systemd.network</title>
28                 <productname>systemd</productname>
29
30                 <authorgroup>
31                         <author>
32                                 <contrib>Developer</contrib>
33                                 <firstname>Tom</firstname>
34                                 <surname>Gundersen</surname>
35                                 <email>teg@jklm.no</email>
36                         </author>
37                 </authorgroup>
38         </refentryinfo>
39
40         <refmeta>
41                 <refentrytitle>systemd.network</refentrytitle>
42                 <manvolnum>5</manvolnum>
43         </refmeta>
44
45         <refnamediv>
46                 <refname>systemd.network</refname>
47                 <refpurpose>Network configuration</refpurpose>
48         </refnamediv>
49
50         <refsynopsisdiv>
51                 <para><filename><replaceable>network</replaceable>.network</filename></para>
52         </refsynopsisdiv>
53
54         <refsect1>
55                 <title>Description</title>
56
57                 <para>Network setup is performed by
58                 <citerefentry><refentrytitle>systemd-networkd</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
59                 </para>
60
61                 <para>Network files must have the extension <filename>.network</filename>;
62                 other extensions are ignored. Networks are applied to links whenever the links
63                 appear.</para>
64
65                 <para>The <filename>.network</filename> files are read from the files located in the
66                 system network directory <filename>/usr/lib/systemd/network</filename>,
67                 the volatile runtime network directory
68                 <filename>/run/systemd/network</filename> and the local administration
69                 network directory <filename>/etc/systemd/network</filename>.
70                 All configuration files are collectively sorted and processed in lexical order,
71                 regardless of the directories in which they live. However, files with
72                 identical filenames replace each other. Files in
73                 <filename>/etc</filename> have the highest priority, files in
74                 <filename>/run</filename> take precedence over files with the same
75                 name in <filename>/usr/lib</filename>. This can be used to override a
76                 system-supplied configuration file with a local file if needed; a symlink in
77                 <filename>/etc</filename> with the same name as a configuration file in
78                 <filename>/usr/lib</filename>, pointing to <filename>/dev/null</filename>,
79                 disables the configuration file entirely.</para>
80
81         </refsect1>
82
83         <refsect1>
84                 <title>[Match] Section Options</title>
85
86                         <para>The network file contains a <literal>[Match]</literal> section,
87                         which determines if a given network file may be applied to a given device;
88                         and a <literal>[Network]</literal> section specifying how the device should
89                         be configured. The first (in lexical order) of the network files that
90                         matches a given device is applied.</para>
91
92                         <para>A network file is said to match a device if each of the entries in the
93                         <literal>[Match]</literal> section matches, or if the section is empty.
94                         The following keys are accepted:</para>
95
96                         <variablelist class='network-directives'>
97                                 <varlistentry>
98                                         <term><varname>MACAddress=</varname></term>
99                                         <listitem>
100                                                 <para>The hardware address.</para>
101                                         </listitem>
102                                 </varlistentry>
103                                 <varlistentry>
104                                         <term><varname>Path=</varname></term>
105                                         <listitem>
106                                                 <para>The persistent path, as exposed by the udev
107                                                 property <literal>ID_PATH</literal>. May contain shell
108                                                 style globs.</para>
109                                         </listitem>
110                                 </varlistentry>
111                                 <varlistentry>
112                                         <term><varname>Driver=</varname></term>
113                                         <listitem>
114                                                 <para>The driver currently bound to the device, as
115                                                 exposed by the udev property <literal>DRIVER</literal>
116                                                 of its parent device, or if that is not set the driver
117                                                 as exposed by <literal>ethtool -i</literal> of the
118                                                 device itself.</para>
119                                         </listitem>
120                                 </varlistentry>
121                                 <varlistentry>
122                                         <term><varname>Type=</varname></term>
123                                         <listitem>
124                                                 <para>The device type, as exposed by the udev property
125                                                 <literal>DEVTYPE</literal>.</para>
126                                         </listitem>
127                                 </varlistentry>
128                                 <varlistentry>
129                                         <term><varname>Name=</varname></term>
130                                         <listitem>
131                                                 <para>The device name, as exposed by the udev property
132                                                 <literal>INTERFACE</literal>. May contain shell style
133                                                 globs.</para>
134                                         </listitem>
135                                 </varlistentry>
136                                 <varlistentry>
137                                         <term><varname>Host=</varname></term>
138                                         <listitem>
139                                                 <para>Matches against the hostname or machine ID of the
140                                                 host. See <literal>ConditionHost=</literal> in
141                                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
142                                                 for details.
143                                                 </para>
144                                         </listitem>
145                                 </varlistentry>
146                                 <varlistentry>
147                                         <term><varname>Virtualization=</varname></term>
148                                         <listitem>
149                                                 <para>Checks whether the system is executed in a virtualized
150                                                 environment and optionally test whether it is a specific
151                                                 implementation. See <literal>ConditionVirtualization=</literal> in
152                                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
153                                                 for details.
154                                                 </para>
155                                         </listitem>
156                                 </varlistentry>
157                                 <varlistentry>
158                                         <term><varname>KernelCommandLine=</varname></term>
159                                         <listitem>
160                                                 <para>Checks whether a specific kernel command line option is
161                                                 set (or if prefixed with the exclamation mark unset). See
162                                                 <literal>ConditionKernelCommandLine=</literal> in
163                                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
164                                                 for details.
165                                                 </para>
166                                         </listitem>
167                                 </varlistentry>
168                                 <varlistentry>
169                                         <term><varname>Architecture=</varname></term>
170                                         <listitem>
171                                                 <para>Checks whether the system is running on a specific
172                                                 architecture. See <literal>ConditionArchitecture=</literal> in
173                                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
174                                                 for details.
175                                                 </para>
176                                         </listitem>
177                                 </varlistentry>
178                         </variablelist>
179
180         </refsect1>
181
182         <refsect1>
183                 <title>[Link] Section Options</title>
184
185                 <para> The <literal>[Link]</literal> section accepts the following keys:</para>
186
187                 <variablelist class='network-directives'>
188                         <varlistentry>
189                                 <term><varname>MACAddress=</varname></term>
190                                 <listitem>
191                                         <para>The hardware address.</para>
192                                 </listitem>
193                         </varlistentry>
194                         <varlistentry>
195                                 <term><varname>MTUBytes=</varname></term>
196                                 <listitem>
197                                         <para>The maximum transmission unit in bytes to
198                                         set for the device. The usual suffixes K, M, G,
199                                         are supported and are understood to the base of
200                                         1024.</para>
201                                 </listitem>
202                         </varlistentry>
203                 </variablelist>
204         </refsect1>
205
206         <refsect1>
207                 <title>[Network] Section Options</title>
208
209                         <para>The <literal>[Network]</literal> section accepts the following keys:</para>
210
211                         <variablelist class='network-directives'>
212                                 <varlistentry>
213                                         <term><varname>Description=</varname></term>
214                                         <listitem>
215                                                 <para>A description of the device. This is only used for
216                                                 presentation purposes.</para>
217                                         </listitem>
218                                 </varlistentry>
219                                 <varlistentry>
220                                         <term><varname>DHCP=</varname></term>
221                                         <listitem>
222                                                 <para>Enables DHCPv4 and/or DHCPv6 support. Accepts
223                                                 <literal>yes</literal>, <literal>no</literal>,
224                                                 <literal>ipv4</literal> or <literal>ipv6</literal>.</para>
225                                         </listitem>
226                                 </varlistentry>
227                                 <varlistentry>
228                                         <term><varname>DHCPServer=</varname></term>
229                                         <listitem>
230                                                 <para>A boolean. Enables a basic DHCPv4 server on the
231                                                 device. Mostly useful for handing out leases to container
232                                                 instances.</para>
233                                         </listitem>
234                                 </varlistentry>
235                                 <varlistentry>
236                                         <term><varname>IPv4LL=</varname></term>
237                                         <listitem>
238                                                 <para>A boolean. When true, enables IPv4 link-local support.
239                                                 </para>
240                                         </listitem>
241                                 </varlistentry>
242                                 <varlistentry>
243                                         <term><varname>IPv4LLRoute=</varname></term>
244                                         <listitem>
245                                                 <para>A boolean. When true, sets up the route needed for
246                                                 non-IPv4LL hosts to communicate with IPv4LL-only hosts. Defaults
247                                                 to false.
248                                                 </para>
249                                         </listitem>
250                                 </varlistentry>
251                                 <varlistentry>
252                                         <term><varname>LLMNR=</varname></term>
253                                         <listitem>
254                                                 <para>A boolean or <literal>resolve</literal>. When true, enables
255                                                 Link-Local Multicast Name Resolution on the link, when set to
256                                                 <literal>resolve</literal> only resolution is enabled, but not
257                                                 announcement. Defaults to true.</para>
258                                         </listitem>
259                                 </varlistentry>
260                                 <varlistentry>
261                                         <term><varname>LLDP=</varname></term>
262                                         <listitem>
263                                                 <para>A boolean. When true, enables LLDP link receive support.
264                                                 </para>
265                                         </listitem>
266                                 </varlistentry>
267                                 <varlistentry>
268                                         <term><varname>Address=</varname></term>
269                                         <listitem>
270                                                 <para>A static IPv4 or IPv6 address and its prefix length,
271                                                 separated by a <literal>/</literal> character. Specify this
272                                                 key more than once to configure several addresses.
273                                                 The format of the address must be as described in
274                                                 <citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
275                                                 This is a short-hand for an [Address] section only containing
276                                                 an Address key (see below). This option may be specified
277                                                 more than once.
278                                                 </para>
279
280                                                 <para>If the specified
281                                                 address is 0.0.0.0
282                                                 (for IPv4) or [::]
283                                                 (for IPv6), a new
284                                                 address range of the
285                                                 requested size is
286                                                 automatically
287                                                 allocated from a
288                                                 system-wide pool of
289                                                 unused ranges. The
290                                                 allocated range is
291                                                 checked against all
292                                                 current network
293                                                 interfaces and all
294                                                 known network
295                                                 configuration files to
296                                                 avoid address range
297                                                 conflicts. The default
298                                                 system-wide pool
299                                                 consists of
300                                                 192.168.0.0/16,
301                                                 172.16.0.0/12 and
302                                                 10.0.0.0/8 for IPv4,
303                                                 and fc00::/7 for
304                                                 IPv6. This
305                                                 functionality is
306                                                 useful to manage a
307                                                 large number of
308                                                 dynamically created
309                                                 network interfaces
310                                                 with the same network
311                                                 configuration and
312                                                 automatic address
313                                                 range
314                                                 assignment.</para>
315
316                                         </listitem>
317                                 </varlistentry>
318                                 <varlistentry>
319                                         <term><varname>Gateway=</varname></term>
320                                         <listitem>
321                                                 <para>The gateway address, which must be in the format described in
322                                                 <citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
323                                                 This is a short-hand for a [Route] section only containing a Gateway
324                                                 key. This option may be specified more than once.</para>
325                                         </listitem>
326                                 </varlistentry>
327                                 <varlistentry>
328                                         <term><varname>DNS=</varname></term>
329                                         <listitem>
330                                                 <para>A DNS server address, which must be in the format described in
331                                                 <citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
332                                                 This option may be specified more than once.</para>
333                                         </listitem>
334                                 </varlistentry>
335                                 <varlistentry>
336                                         <term><varname>Domains=</varname></term>
337                                         <listitem>
338                                                 <para>The domains used for DNS resolution over this link.</para>
339                                         </listitem>
340                                 </varlistentry>
341                                 <varlistentry>
342                                         <term><varname>NTP=</varname></term>
343                                         <listitem>
344                                                 <para>An NTP server address. This option may be specified more than once.</para>
345                                         </listitem>
346                                 </varlistentry>
347                                 <varlistentry>
348                                         <term><varname>IPForward=</varname></term>
349                                         <listitem><para>Configures IP
350                                         forwarding for the network
351                                         interface. If enabled incoming
352                                         packets on the network
353                                         interface will be forwarded to
354                                         other interfaces according to
355                                         the routing table. Takes a
356                                         boolean
357                                         argument.</para></listitem>
358                                 </varlistentry>
359                                 <varlistentry>
360                                         <term><varname>IPMasquerade=</varname></term>
361                                         <listitem><para>Configures IP
362                                         masquerading for the network
363                                         interface. If enabled packets
364                                         forwarded from the network
365                                         interface will be appear as
366                                         coming from the local
367                                         host. Takes a boolean
368                                         argument. Implies
369                                         <varname>IPForward=yes</varname>.</para></listitem>
370                                 </varlistentry>
371                                 <varlistentry>
372                                         <term><varname>Bridge=</varname></term>
373                                         <listitem>
374                                                 <para>The name of the bridge to add the link to.</para>
375                                         </listitem>
376                                 </varlistentry>
377                                 <varlistentry>
378                                         <term><varname>Bond=</varname></term>
379                                         <listitem>
380                                                 <para>The name of the bond to add the link to.</para>
381                                         </listitem>
382                                 </varlistentry>
383                                 <varlistentry>
384                                         <term><varname>VLAN=</varname></term>
385                                         <listitem>
386                                                 <para>The name of a VLAN to create on the link. This option
387                                                 may be specified more than once.</para>
388                                         </listitem>
389                                 </varlistentry>
390                                 <varlistentry>
391                                         <term><varname>MACVLAN=</varname></term>
392                                         <listitem>
393                                                 <para>The name of a MACVLAN to create on the link. This option
394                                                 may be specified more than once.</para>
395                                         </listitem>
396                                 </varlistentry>
397                                 <varlistentry>
398                                         <term><varname>VXLAN=</varname></term>
399                                         <listitem>
400                                                 <para>The name of a VXLAN to create on the link. This option
401                                                 may be specified more than once.</para>
402                                         </listitem>
403                                 </varlistentry>
404                                 <varlistentry>
405                                         <term><varname>Tunnel=</varname></term>
406                                         <listitem>
407                                                 <para>The name of a Tunnel to create on the link. This option
408                                                 may be specified more than once.</para>
409                                         </listitem>
410                                 </varlistentry>
411                         </variablelist>
412
413         </refsect1>
414
415         <refsect1>
416                 <title>[Address] Section Options</title>
417
418                         <para>An <literal>[Address]</literal> section accepts the following keys.
419                         Specify several <literal>[Address]</literal> sections to configure several
420                         addresses.</para>
421
422                         <variablelist class='network-directives'>
423                                 <varlistentry>
424                                         <term><varname>Address=</varname></term>
425                                         <listitem>
426                                                 <para>As in the <literal>[Network]</literal> section. This key is mandatory.</para>
427                                         </listitem>
428                                 </varlistentry>
429                                 <varlistentry>
430                                         <term><varname>Peer=</varname></term>
431                                         <listitem>
432                                                 <para>The peer address in a point-to-point connection. Accepts the same format as
433                                                 the <literal>Address</literal> key.</para>
434                                         </listitem>
435                                 </varlistentry>
436                                 <varlistentry>
437                                         <term><varname>Broadcast=</varname></term>
438                                         <listitem>
439                                                 <para>The broadcast address, which must be in the format described in
440                                                 <citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
441                                                 This key only applies to IPv4 addresses. If it is not given, it is
442                                                 derived from the <literal>Address</literal> key.</para>
443                                         </listitem>
444                                 </varlistentry>
445                                 <varlistentry>
446                                         <term><varname>Label=</varname></term>
447                                         <listitem>
448                                                 <para>An address label.</para>
449                                         </listitem>
450                                 </varlistentry>
451                         </variablelist>
452         </refsect1>
453
454         <refsect1>
455                 <title>[Route] Section Options</title>
456                         <para>The <literal>[Route]</literal> section accepts the following keys. Specify
457                         several <literal>[Route]</literal> sections to configure several routes.</para>
458
459                         <variablelist class='network-directives'>
460                                 <varlistentry>
461                                         <term><varname>Gateway=</varname></term>
462                                         <listitem>
463                                                 <para>As in the <literal>[Network]</literal> section.</para>
464                                         </listitem>
465                                 </varlistentry>
466                                 <varlistentry>
467                                         <term><varname>Destination=</varname></term>
468                                         <listitem>
469                                                 <para>The destination prefix of the route. Possibly followed by a slash and the
470                                                 prefixlength. If omitted, a full-length host route is assumed.</para>
471                                         </listitem>
472                                 </varlistentry>
473                                 <varlistentry>
474                                         <term><varname>Source=</varname></term>
475                                         <listitem>
476                                                 <para>The source prefix of the route. Possibly followed by a slash and the
477                                                 prefixlength. If omitted, a full-length host route is assumed.</para>
478                                         </listitem>
479                                 </varlistentry>
480                                 <varlistentry>
481                                         <term><varname>Metric=</varname></term>
482                                         <listitem>
483                                                 <para>The metric of the route. An unsigned integer</para>
484                                         </listitem>
485                                 </varlistentry>
486                         </variablelist>
487         </refsect1>
488
489         <refsect1>
490                 <title>[DHCP] Section Options</title>
491                         <para>The <literal>[DHCP]</literal> section accepts the following keys:</para>
492
493                         <variablelist class='network-directives'>
494                                 <varlistentry>
495                                         <term><varname>UseDNS=</varname></term>
496                                         <listitem>
497                                                 <para>When true (the default), the DNS servers received from the DHCP server will
498                                                 be used and take precedence over any statically configured ones.</para>
499                                         </listitem>
500                                 </varlistentry>
501                                 <varlistentry>
502                                         <term><varname>UseMTU=</varname></term>
503                                         <listitem>
504                                                 <para>When true, the interface maximum transmission unit from the DHCP server will
505                                                 be used on the current link. Defaults to false.</para>
506                                         </listitem>
507                                 </varlistentry>
508                                 <varlistentry>
509                                         <term><varname>SendHostname=</varname></term>
510                                         <listitem>
511                                                 <para>When true (the default), the machine's hostname will be sent to the DHCP
512                                                 server</para>
513                                         </listitem>
514                                 </varlistentry>
515                                 <varlistentry>
516                                         <term><varname>UseHostname=</varname></term>
517                                         <listitem>
518                                                 <para>When true (the default), the hostname received from the DHCP server
519                                                 will be used as the transient hostname.</para>
520                                         </listitem>
521                                 </varlistentry>
522                                 <varlistentry>
523                                         <term><varname>UseDomains=</varname></term>
524                                         <listitem>
525                                                 <para>When true (not the default), the domain name received from the DHCP server
526                                                 will be used for DNS resolution over this link.</para>
527                                         </listitem>
528                                 </varlistentry>
529                                 <varlistentry>
530                                         <term><varname>UseRoutes=</varname></term>
531                                         <listitem>
532                                                 <para>When true (the default), the static routes will be requested from the DHCP server
533                                                 and added to the routing table with metric of 1024.</para>
534                                         </listitem>
535                                 </varlistentry>
536                                 <varlistentry>
537                                         <term><varname>CriticalConnection=</varname></term>
538                                         <listitem>
539                                                 <para>When true, the connection will never be torn down even if the DHCP lease
540                                                 expires. This is contrary to the DHCP specification, but may be the best choice
541                                                 if, say, the root filesystem relies on this connection. Defaults to false.</para>
542                                         </listitem>
543                                 </varlistentry>
544                                 <varlistentry>
545                                         <term><varname>VendorClassIdentifier=</varname></term>
546                                         <listitem>
547                                                 <para>The vendor class identifier used to identify vendor type and configuration.</para>
548                                         </listitem>
549                                 </varlistentry>
550                                 <varlistentry>
551                                         <term><varname>RequestBroadcast=</varname></term>
552                                         <listitem>
553                                                 <para>Request the server to use broadcast messages before the IP address has been
554                                                 configured. This is necessary for devices that cannot receive RAW packets, or that
555                                                 cannot receive packets at all before an IP address has been configured. On the other
556                                                 hand, this must not be enabled on networks where broadcasts are filtered out.</para>
557                                         </listitem>
558                                 </varlistentry>
559                                 <varlistentry>
560                                         <term><varname>RouteMetric=</varname></term>
561                                         <listitem>
562                                                 <para>Set the routing metric for routes specified by the DHCP server.</para>
563                                         </listitem>
564                                 </varlistentry>
565                        </variablelist>
566
567         </refsect1>
568
569         <refsect1>
570                 <title>[Bridge] Section Options</title>
571                         <para>The <literal>[Bridge]</literal> section accepts the following keys.</para>
572                         <variablelist class='network-directives'>
573                                 <varlistentry>
574                                         <term><varname>Cost=</varname></term>
575                                         <listitem>
576                                           <para>Each port in a bridge may have different speed. Cost is used to decide which link to use. Faster interfaces should have lower costs</para>
577                                         </listitem>
578                                 </varlistentry>
579                         </variablelist>
580         </refsect1>
581
582         <refsect1>
583                 <title>[BridgeFDB] Section Options</title>
584                         <para>The <literal>[BridgeFDB]</literal> section manages the forwarding database table of a port and accepts the following keys. Specify
585                         several <literal>[BridgeFDB]</literal> sections to configure several static MAC table entries.</para>
586
587                         <variablelist class='network-directives'>
588                                 <varlistentry>
589                                         <term><varname>MACAddress=</varname></term>
590                                         <listitem>
591                                                 <para>As in the <literal>[Network]</literal> section. This key is mandatory.</para>
592                                         </listitem>
593                                 </varlistentry>
594                                 <varlistentry>
595                                         <term><varname>VLANId=</varname></term>
596                                         <listitem>
597                                                 <para>The VLAN Id for the new static MAC table entry.
598                                                 If omitted, no VLAN Id info is appended to the new static MAC table entry.</para>
599                                         </listitem>
600                                 </varlistentry>
601                         </variablelist>
602         </refsect1>
603
604         <refsect1>
605                 <title>Example</title>
606                 <example>
607                         <title>/etc/systemd/network/50-static.network</title>
608
609                         <programlisting>[Match]
610 Name=enp2s0
611
612 [Network]
613 Address=192.168.0.15/24
614 Gateway=192.168.0.1</programlisting>
615                 </example>
616
617                 <example>
618                         <title>/etc/systemd/network/80-dhcp.network</title>
619
620                         <programlisting>[Match]
621 Name=en*
622
623 [Network]
624 DHCP=both</programlisting>
625                 </example>
626
627                 <example>
628                         <title>/etc/systemd/network/bridge-static.network</title>
629
630                         <programlisting>[Match]
631 Name=bridge0
632
633 [Network]
634 Address=192.168.0.15/24
635 Gateway=192.168.0.1
636 DNS=192.168.0.1</programlisting>
637                 </example>
638
639                 <example>
640                         <title>/etc/systemd/network/bridge-slave-interface.network</title>
641
642                         <programlisting>[Match]
643 Name=enp2s0
644
645 [Network]
646 Bridge=bridge0</programlisting>
647                 </example>
648                 <example>
649                         <title>/etc/systemd/network/ipip.network</title>
650
651                         <programlisting>[Match]
652 Name=em1
653
654 [Network]
655 Tunnel=ipip-tun</programlisting>
656                 </example>
657
658                 <example>
659                         <title>/etc/systemd/network/sit.network</title>
660
661                         <programlisting>[Match]
662 Name=em1
663
664 [Network]
665 Tunnel=sit-tun</programlisting>
666                 </example>
667
668                 <example>
669                         <title>/etc/systemd/network/gre.network</title>
670
671                         <programlisting>[Match]
672 Name=em1
673
674 [Network]
675 Tunnel=gre-tun</programlisting>
676                 </example>
677
678                 <example>
679                         <title>/etc/systemd/network/vti.network</title>
680
681                         <programlisting>[Match]
682 Name=em1
683
684 [Network]
685 Tunnel=vti-tun</programlisting>
686                 </example>
687         </refsect1>
688
689         <refsect1>
690                 <title>See Also</title>
691                 <para>
692                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
693                         <citerefentry><refentrytitle>systemd-networkd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
694                         <citerefentry><refentrytitle>systemd.link</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
695                         <citerefentry><refentrytitle>systemd.netdev</refentrytitle><manvolnum>5</manvolnum></citerefentry>
696                 </para>
697         </refsect1>
698
699 </refentry>