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
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
|
<?xml version='1.0'?> <!--*-nxml-*-->
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
<!--
This file is part of systemd.
Copyright 2013 Tom Gundersen
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
-->
<refentry id="systemd.network" conditional='ENABLE_NETWORKD'>
<refentryinfo>
<title>systemd.network</title>
<productname>systemd</productname>
<authorgroup>
<author>
<contrib>Developer</contrib>
<firstname>Tom</firstname>
<surname>Gundersen</surname>
<email>teg@jklm.no</email>
</author>
</authorgroup>
</refentryinfo>
<refmeta>
<refentrytitle>systemd.network</refentrytitle>
<manvolnum>5</manvolnum>
</refmeta>
<refnamediv>
<refname>systemd.network</refname>
<refpurpose>Network configuration</refpurpose>
</refnamediv>
<refsynopsisdiv>
<para><filename><replaceable>network</replaceable>.network</filename></para>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para>Network setup is performed by
<citerefentry><refentrytitle>systemd-networkd</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
</para>
<para>Network files must have the extension <filename>.network</filename>;
other extensions are ignored. Networks are applied to links whenever the links
appear.</para>
<para>The <filename>.network</filename> files are read from the files located in the
system network directory <filename>/usr/lib/systemd/network</filename>,
the volatile runtime network directory
<filename>/run/systemd/network</filename> and the local administration
network directory <filename>/etc/systemd/network</filename>.
All configuration files are collectively sorted and processed in lexical order,
regardless of the directories in which they live. However, files with
identical filenames replace each other. Files in
<filename>/etc</filename> have the highest priority, files in
<filename>/run</filename> take precedence over files with the same
name in <filename>/usr/lib</filename>. This can be used to override a
system-supplied configuration file with a local file if needed; a symlink in
<filename>/etc</filename> with the same name as a configuration file in
<filename>/usr/lib</filename>, pointing to <filename>/dev/null</filename>,
disables the configuration file entirely.</para>
</refsect1>
<refsect1>
<title>[Match] Section Options</title>
<para>The network file contains a <literal>[Match]</literal> section,
which determines if a given network file may be applied to a given device;
and a <literal>[Network]</literal> section specifying how the device should
be configured. The first (in lexical order) of the network files that
matches a given device is applied.</para>
<para>A network file is said to match a device if each of the entries in the
<literal>[Match]</literal> section matches, or if the section is empty.
The following keys are accepted:</para>
<variablelist class='network-directives'>
<varlistentry>
<term><varname>MACAddress=</varname></term>
<listitem>
<para>The hardware address.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>Path=</varname></term>
<listitem>
<para>The persistent path, as exposed by the udev
property <literal>ID_PATH</literal>. May contain shell
style globs.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>Driver=</varname></term>
<listitem>
<para>The driver currently bound to the device, as
exposed by the udev property <literal>DRIVER</literal>
of its parent device, or if that is not set the driver
as exposed by <literal>ethtool -i</literal> of the
device itself.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>Type=</varname></term>
<listitem>
<para>The device type, as exposed by the udev property
<literal>DEVTYPE</literal>.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>Name=</varname></term>
<listitem>
<para>The device name, as exposed by the udev property
<literal>INTERFACE</literal>. May contain shell style
globs.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>Host=</varname></term>
<listitem>
<para>Matches against the hostname or machine ID of the
host. See <literal>ConditionHost=</literal> in
<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
for details.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>Virtualization=</varname></term>
<listitem>
<para>Checks whether the system is executed in a virtualized
environment and optionally test whether it is a specific
implementation. See <literal>ConditionVirtualization=</literal> in
<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
for details.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>KernelCommandLine=</varname></term>
<listitem>
<para>Checks whether a specific kernel command line option is
set (or if prefixed with the exclamation mark unset). See
<literal>ConditionKernelCommandLine=</literal> in
<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
for details.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>Architecture=</varname></term>
<listitem>
<para>Checks whether the system is running on a specific
architecture. See <literal>ConditionArchitecture=</literal> in
<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
for details.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>[Network] Section Options</title>
<para>The <literal>[Network]</literal> section accepts the following keys:</para>
<variablelist class='network-directives'>
<varlistentry>
<term><varname>Description=</varname></term>
<listitem>
<para>A description of the device. This is only used for
presentation purposes.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>DHCP=</varname></term>
<listitem>
<para>Enables DHCPv4 and/or DHCPv6 support. Accepts
<literal>both</literal>, <literal>none</literal>,
<literal>v4</literal> or <literal>v6</literal>.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>DHCPServer=</varname></term>
<listitem>
<para>A boolean. Enables a basic DHCPv4 server on the
device. Mostly useful for handing out leases to container
instances.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>IPv4LL=</varname></term>
<listitem>
<para>A boolean. When true, enables IPv4 link-local support.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>IPv4LLRoute=</varname></term>
<listitem>
<para>A boolean. When true, sets up the route needed for
non-IPv4LL hosts to communicate with IPv4LL-only hosts. Defaults
to false.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>LLMNR=</varname></term>
<listitem>
<para>A boolean or <literal>resolve</literal>. When true, enables
Link-Local Multicast Name Resolution on the link, when set to
<literal>resolve</literal> only resolution is enabled, but not
announcement. Defaults to true.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>Address=</varname></term>
<listitem>
<para>A static IPv4 or IPv6 address and its prefix length,
separated by a <literal>/</literal> character. Specify this
key more than once to configure several addresses.
The format of the address must be as described in
<citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
This is a short-hand for an [Address] section only containing
an Address key (see below). This option may be specified
more than once.
</para>
<para>If the specified
address is 0.0.0.0
(for IPv4) or [::]
(for IPv6), a new
address range of the
requested size is
automatically
allocated from a
system-wide pool of
unused ranges. The
allocated range is
checked against all
current network
interfaces and all
known network
configuration files to
avoid address range
conflicts. The default
system-wide pool
consists of
192.168.0.0/16,
172.16.0.0/12 and
10.0.0.0/8 for IPv4,
and fc00::/7 for
IPv6. This
functionality is
useful to manage a
large number of
dynamically created
network interfaces
with the same network
configuration and
automatic address
range
assignment.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>Gateway=</varname></term>
<listitem>
<para>The gateway address, which must be in the format described in
<citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
This is a short-hand for a [Route] section only containing a Gateway
key. This option may be specified more than once.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>DNS=</varname></term>
<listitem>
<para>A DNS server address, which must be in the format described in
<citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
This option may be specified more than once.</para>
</listitem>
</varlistentry>
<!-- TODO: document NTP= option when it is actually used somewhere -->
<varlistentry>
<term><varname>Bridge=</varname></term>
<listitem>
<para>The name of the bridge to add the link to.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>Bond=</varname></term>
<listitem>
<para>The name of the bond to add the link to.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>VLAN=</varname></term>
<listitem>
<para>The name of a VLAN to create on the link. This option
may be specified more than once.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>MACVLAN=</varname></term>
<listitem>
<para>The name of a MACVLAN to create on the link. This option
may be specified more than once.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>VXLAN=</varname></term>
<listitem>
<para>The name of a VXLAN to create on the link. This option
may be specified more than once.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>Tunnel=</varname></term>
<listitem>
<para>The name of a Tunnel to create on the link. This option
may be specified more than once.</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>[Address] Section Options</title>
<para>An <literal>[Address]</literal> section accepts the following keys.
Specify several <literal>[Address]</literal> sections to configure several
addresses.</para>
<variablelist class='network-directives'>
<varlistentry>
<term><varname>Address=</varname></term>
<listitem>
<para>As in the <literal>[Network]</literal> section. This key is mandatory.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>Peer=</varname></term>
<listitem>
<para>The peer address in a point-to-point connection. Accepts the same format as
the <literal>Address</literal> key.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>Broadcast=</varname></term>
<listitem>
<para>The broadcast address, which must be in the format described in
<citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
This key only applies to IPv4 addresses. If it is not given, it is
derived from the <literal>Address</literal> key.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>Label=</varname></term>
<listitem>
<para>An address label.</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>[Route] Section Options</title>
<para>The <literal>[Route]</literal> section accepts the following keys. Specify
several <literal>[Route]</literal> sections to configure several routes.</para>
<variablelist class='network-directives'>
<varlistentry>
<term><varname>Gateway=</varname></term>
<listitem>
<para>As in the <literal>[Network]</literal> section. This key is mandatory.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>Destination=</varname></term>
<listitem>
<para>The destination prefix of the route. Possibly followed by a slash and the
prefixlength. If ommitted, a full-length host route is assumed.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>Metric=</varname></term>
<listitem>
<para>The metric of the route. An unsigned integer</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>[DHCP] Section Options</title>
<para>The <literal>[DHCP]</literal> section accepts the following keys:</para>
<variablelist class='network-directives'>
<varlistentry>
<term><varname>UseDNS=</varname></term>
<listitem>
<para>When true (the default), the DNS servers received from the DHCP server will
be used and take precedence over any statically configured ones.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>UseMTU=</varname></term>
<listitem>
<para>When true, the interface maximum transmission unit from the DHCP server will
be used on the current link. Defaults to false.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>SendHostname=</varname></term>
<listitem>
<para>When true (the default), the machine's hostname will be sent to the DHCP
server</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>UseHostname=</varname></term>
<listitem>
<para>When true (the default), the hostname received from the DHCP server
will be used as the transient hostname.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>UseRoutes=</varname></term>
<listitem>
<para>When true (the default), the static routes will be requested from the DHCP server
and added to the routing table with metric of 1024.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>CriticalConnection=</varname></term>
<listitem>
<para>When true, the connection will never be torn down even if the DHCP lease
expires. This is contrary to the DHCP specification, but may be the best choice
if, say, the root filesystem relies on this connection. Defaults to false.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>VendorClassIdentifier=</varname></term>
<listitem>
<para>The vendor class identifier used to identify vendor type and configuration.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>RequestBroadcast=</varname></term>
<listitem>
<para>Request the server to use broadcast messages before the IP address has been
configured. This is necessary for devices that cannot receive RAW packets, or that
cannot receive packets at all before an IP address has been configured. On the other
hand, this must not be enabled on networks where broadcasts are filtered out.</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Example</title>
<example>
<title>/etc/systemd/network/50-static.network</title>
<programlisting>[Match]
Name=enp2s0
[Network]
Address=192.168.0.15/24
Gateway=192.168.0.1</programlisting>
</example>
<example>
<title>/etc/systemd/network/80-dhcp.network</title>
<programlisting>[Match]
Name=en*
[Network]
DHCP=both</programlisting>
</example>
<example>
<title>/etc/systemd/network/bridge-static.network</title>
<programlisting>[Match]
Name=bridge0
[Network]
Address=192.168.0.15/24
Gateway=192.168.0.1
DNS=192.168.0.1</programlisting>
</example>
<example>
<title>/etc/systemd/network/bridge-slave-interface.network</title>
<programlisting>[Match]
Name=enp2s0
[Network]
Bridge=bridge0</programlisting>
</example>
<example>
<title>/etc/systemd/network/ipip.network</title>
<programlisting>[Match]
Name=em1
[Network]
Tunnel=ipip-tun</programlisting>
</example>
<example>
<title>/etc/systemd/network/sit.network</title>
<programlisting>[Match]
Name=em1
[Network]
Tunnel=sit-tun</programlisting>
</example>
<example>
<title>/etc/systemd/network/gre.network</title>
<programlisting>[Match]
Name=em1
[Network]
Tunnel=gre-tun</programlisting>
</example>
<example>
<title>/etc/systemd/network/vti.network</title>
<programlisting>[Match]
Name=em1
[Network]
Tunnel=vti-tun</programlisting>
</example>
</refsect1>
<refsect1>
<title>See Also</title>
<para>
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd-networkd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd.netdev</refentrytitle><manvolnum>5</manvolnum></citerefentry>
</para>
</refsect1>
</refentry>
|