chiark / gitweb /
Add support for DHCP static route options
[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
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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>[Network] Section Options</title>
184
185                         <para>The <literal>[Network]</literal> section accepts the following keys:</para>
186
187                         <variablelist class='network-directives'>
188                                 <varlistentry>
189                                         <term><varname>Description=</varname></term>
190                                         <listitem>
191                                                 <para>A description of the device. This is only used for
192                                                 presentation purposes.</para>
193                                         </listitem>
194                                 </varlistentry>
195                                 <varlistentry>
196                                         <term><varname>DHCP=</varname></term>
197                                         <listitem>
198                                                 <para>Enables DHCPv4 and/or DHCPv6 support. Accepts
199                                                 <literal>both</literal>, <literal>none</literal>,
200                                                 <literal>v4</literal> or <literal>v6</literal>.</para>
201                                         </listitem>
202                                 </varlistentry>
203                                 <varlistentry>
204                                         <term><varname>IPv4LL=</varname></term>
205                                         <listitem>
206                                                 <para>A boolean. When true, enables IPv4 link-local support.
207                                                 If <literal>DHCP=</literal> is also true, acquiring DHCP address
208                                                 will deprecate previously acquired IPv4 link-local address or
209                                                 stop acquiring process if one has not been acquired before.
210                                                 </para>
211                                         </listitem>
212                                 </varlistentry>
213                                 <varlistentry>
214                                         <term><varname>Address=</varname></term>
215                                         <listitem>
216                                                 <para>A static IPv4 or IPv6 address and its prefix length,
217                                                 separated by a <literal>/</literal> character. Specify this
218                                                 key more than once to configure several addresses.
219                                                 The format of the address must be as described in
220                                                 <citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
221                                                 This is a short-hand for an [Address] section only containing
222                                                 an Address key (see below). This option may be specified
223                                                 more than once.
224                                                 </para>
225
226                                                 <para>If the specified
227                                                 address is 0.0.0.0
228                                                 (for IPv4) or [::]
229                                                 (for IPv6), a new
230                                                 address range of the
231                                                 requested size is
232                                                 automatically
233                                                 allocated from a
234                                                 system-wide pool of
235                                                 unused ranges. The
236                                                 allocated range is
237                                                 checked against all
238                                                 current network
239                                                 interfaces and all
240                                                 known network
241                                                 configuration files to
242                                                 avoid address range
243                                                 conflicts. The default
244                                                 system-wide pool
245                                                 consists of
246                                                 192.168.0.0/16,
247                                                 172.16.0.0/12 and
248                                                 10.0.0.0/8 for IPv4,
249                                                 and fc00::/7 for
250                                                 IPv6. This
251                                                 functionality is
252                                                 useful to manage a
253                                                 large number of
254                                                 dynamically created
255                                                 network interfaces
256                                                 with the same network
257                                                 configuration and
258                                                 automatic address
259                                                 range
260                                                 assignment.</para>
261
262                                         </listitem>
263                                 </varlistentry>
264                                 <varlistentry>
265                                         <term><varname>Gateway=</varname></term>
266                                         <listitem>
267                                                 <para>The gateway address, which must be in the format described in
268                                                 <citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
269                                                 This is a short-hand for a [Route] section only containing a Gateway
270                                                 key. This option may be specified more than once.</para>
271                                         </listitem>
272                                 </varlistentry>
273                                 <varlistentry>
274                                         <term><varname>DNS=</varname></term>
275                                         <listitem>
276                                                 <para>A DNS server address, which must be in the format described in
277                                                 <citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
278                                                 This option may be specified more than once.</para>
279                                         </listitem>
280                                 </varlistentry>
281                                 <varlistentry>
282                                         <term><varname>Bridge=</varname></term>
283                                         <listitem>
284                                                 <para>The name of the bridge to add the link to.</para>
285                                         </listitem>
286                                 </varlistentry>
287                                 <varlistentry>
288                                         <term><varname>Bond=</varname></term>
289                                         <listitem>
290                                                 <para>The name of the bond to add the link to.</para>
291                                         </listitem>
292                                 </varlistentry>
293                                 <varlistentry>
294                                         <term><varname>VLAN=</varname></term>
295                                         <listitem>
296                                                 <para>The name of a VLAN to create on the link. This option
297                                                 may be specified more than once.</para>
298                                         </listitem>
299                                 </varlistentry>
300                                 <varlistentry>
301                                         <term><varname>MACVLAN=</varname></term>
302                                         <listitem>
303                                                 <para>The name of a MACVLAN to create on the link. This option
304                                                 may be specified more than once.</para>
305                                         </listitem>
306                                 </varlistentry>
307                         </variablelist>
308
309         </refsect1>
310
311         <refsect1>
312                 <title>[Address] Section Options</title>
313
314                         <para>An <literal>[Address]</literal> section accepts the following keys.
315                         Specify several <literal>[Address]</literal> sections to configure several
316                         addresses.</para>
317
318                         <variablelist class='network-directives'>
319                                 <varlistentry>
320                                         <term><varname>Address=</varname></term>
321                                         <listitem>
322                                                 <para>As in the <literal>[Network]</literal> section. This key is mandatory.</para>
323                                         </listitem>
324                                 </varlistentry>
325                                 <varlistentry>
326                                         <term><varname>Broadcast=</varname></term>
327                                         <listitem>
328                                                 <para>The broadcast address, which must be in the format described in
329                                                 <citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
330                                                 This key only applies to IPv4 addresses. If it is not given, it is
331                                                 derived from the <literal>Address</literal> key.</para>
332                                         </listitem>
333                                 </varlistentry>
334                                 <varlistentry>
335                                         <term><varname>Label=</varname></term>
336                                         <listitem>
337                                                 <para>An address label.</para>
338                                         </listitem>
339                                 </varlistentry>
340                         </variablelist>
341         </refsect1>
342
343         <refsect1>
344                 <title>[Route] Section Options</title>
345                         <para>The <literal>[Route]</literal> section accepts the following keys. Specify
346                         several <literal>[Route]</literal> sections to configure several routes.</para>
347
348                         <variablelist class='network-directives'>
349                                 <varlistentry>
350                                         <term><varname>Gateway=</varname></term>
351                                         <listitem>
352                                                 <para>As in the <literal>[Network]</literal> section. This key is mandatory.</para>
353                                         </listitem>
354                                 </varlistentry>
355                                 <varlistentry>
356                                         <term><varname>Destination=</varname></term>
357                                         <listitem>
358                                                 <para>The destination prefix of the route. Possibly followed by a slash and the
359                                                 prefixlength. If ommitted, a full-length host route is assumed.</para>
360                                         </listitem>
361                                 </varlistentry>
362                         </variablelist>
363         </refsect1>
364
365         <refsect1>
366                 <title>[DHCP] Section Options</title>
367                         <para>The <literal>[DHCP]</literal> section accepts the following keys:</para>
368
369                         <variablelist class='network-directives'>
370                                 <varlistentry>
371                                         <term><varname>UseDNS=</varname></term>
372                                         <listitem>
373                                                 <para>When true (the default), the DNS servers received from the DHCP server will
374                                                 be used and take precedence over any statically configured ones.</para>
375                                         </listitem>
376                                 </varlistentry>
377                                 <varlistentry>
378                                         <term><varname>UseMTU=</varname></term>
379                                         <listitem>
380                                                 <para>When true, the interface maximum transmission unit from the DHCP server will
381                                                 be used on the current link. Defaults to false.</para>
382                                         </listitem>
383                                 </varlistentry>
384                                 <varlistentry>
385                                         <term><varname>UseHostname=</varname></term>
386                                         <listitem>
387                                                 <para>When true (the default), the hostname received from the DHCP server
388                                                 will be used as the transient hostname.</para>
389                                         </listitem>
390                                 </varlistentry>
391                                 <varlistentry>
392                                         <term><varname>UseRoutes=</varname></term>
393                                         <listitem>
394                                                 <para>When true (the default), the static routes will be requested from the DHCP server
395                                                 and added to the routing table with metric of 1024.</para>
396                                         </listitem>
397                                 </varlistentry>
398                                 <varlistentry>
399                                         <term><varname>CriticalConnection=</varname></term>
400                                         <listitem>
401                                                 <para>When true, the connection will never be torn down even if the DHCP lease
402                                                 expires. This is contrary to the DHCP specification, but may be the best choice
403                                                 if, say, the root filesystem relies on this connection. Defaults to false.</para>
404                                         </listitem>
405                                 </varlistentry>
406                        </variablelist>
407
408         </refsect1>
409
410         <refsect1>
411                 <title>Example</title>
412                 <example>
413                         <title>/etc/systemd/network/50-static.network</title>
414
415                         <programlisting>[Match]
416 Name=enp2s0
417
418 [Network]
419 Address=192.168.0.15/24
420 Gateway=192.168.0.1</programlisting>
421                 </example>
422
423                 <example>
424                         <title>/etc/systemd/network/80-dhcp.network</title>
425
426                         <programlisting>[Match]
427 Name=en*
428
429 [Network]
430 DHCP=yes</programlisting>
431                 </example>
432
433                 <example>
434                         <title>/etc/systemd/network/bridge-static.network</title>
435
436                         <programlisting>[Match]
437 Name=bridge0
438
439 [Network]
440 Address=192.168.0.15/24
441 Gateway=192.168.0.1
442 DNS=192.168.0.1</programlisting>
443                 </example>
444
445                 <example>
446                         <title>/etc/systemd/network/bridge-slave-interface.network</title>
447
448                         <programlisting>[Match]
449 Name=enp2s0
450
451 [Network]
452 Bridge=bridge0</programlisting>
453                 </example>
454         </refsect1>
455
456         <refsect1>
457                 <title>See Also</title>
458                 <para>
459                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
460                         <citerefentry><refentrytitle>systemd-networkd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
461                         <citerefentry><refentrytitle>systemd.netdev</refentrytitle><manvolnum>5</manvolnum></citerefentry>
462                 </para>
463         </refsect1>
464
465 </refentry>