man/systemd-networkd.service.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-networkd.service" conditional='ENABLE_NETWORKD'>
  25
  26         <refentryinfo>
  27                 <title>systemd-networkd.service</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-networkd.service</refentrytitle>
  42                 <manvolnum>8</manvolnum>
  43         </refmeta>
  44
  45         <refnamediv>
  46                 <refname>systemd-networkd.service</refname>
  47                 <refname>systemd-networkd</refname>
  48                 <refpurpose>Network manager</refpurpose>
  49         </refnamediv>
  50
  51         <refsynopsisdiv>
  52                 <para><filename>systemd-networkd.service</filename></para>
  53                 <para><filename>/usr/lib/systemd/systemd-networkd</filename></para>
  54         </refsynopsisdiv>
  55
  56         <refsect1>
  57                 <title>Description</title>
  58
  59                 <para><command>systemd-networkd</command> is a system
  60                 service that manages networks. It detects and configures
  61                 network devices as they appear, as well as creating virtual
  62                 network devices.</para>
  63
  64                 <para>To configure low-level link settings independently of
  65                 networks, see
  66                 <citerefentry><refentrytitle>udev</refentrytitle><manvolnum>7</manvolnum></citerefentry>
  67                 .</para>
  68
  69                 <para>Network configurations applied before networkd is started
  70                 are not removed, and static configuration applied by networkd
  71                 are not removed when networkd exits. This ensures restarting
  72                 networkd does not cut the network connection, and, in particular,
  73                 that it is safe to transition between the initrd and the real root,
  74                 and back.</para>
  75         </refsect1>
  76
  77         <refsect1><title>Configuration Files</title>
  78                 <para>The configuration files are read from the files located in the
  79                 system network directory <filename>/usr/lib/systemd/network</filename>,
  80                 the volatile runtime network directory
  81                 <filename>/run/systemd/network</filename> and the local administration
  82                 network directory <filename>/etc/systemd/network</filename>.
  83                 All configuration files are collectively sorted and processed in lexical order,
  84                 regardless of the directories in which they live. However, files with
  85                 identical filenames replace each other. Files in
  86                 <filename>/etc</filename> have the highest priority, files in
  87                 <filename>/run</filename> take precedence over files with the same
  88                 name in <filename>/usr/lib</filename>. This can be used to override a
  89                 system-supplied configuration file with a local file if needed; a symlink in
  90                 <filename>/etc</filename> with the same name as a configuration file in
  91                 <filename>/usr/lib</filename>, pointing to <filename>/dev/null</filename>,
  92                 disables the configuration file entirely.</para>
  93
  94                 <refsect2><title>Virtual Network Devices</title>
  95                         <para>Virtual Network Device files must have the extension
  96                         <filename>.netdev</filename>; other extensions are ignored. Virtual
  97                         network devices are created as soon as networkd is started.</para>
  98
  99                         <para>A virtual network device is only created if the
 100                         <literal>[Match]</literal> section matches the current
 101                         environment, or if the section is empty. The following keys are accepted:</para>
 102
 103                         <variablelist class='network-directives'>
 104                                 <varlistentry>
 105                                         <term><varname>Host</varname></term>
 106                                         <listitem>
 107                                                 <para>Matches against the hostname or machine ID of the
 108                                                 host. See <literal>ConditionHost=</literal> in
 109                                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 110                                                 for details.
 111                                                 </para>
 112                                         </listitem>
 113                                 </varlistentry>
 114                                 <varlistentry>
 115                                         <term><varname>Virtualization</varname></term>
 116                                         <listitem>
 117                                                 <para>Checks whether the system is executed in a virtualized
 118                                                 environment and optionally test whether it is a specific
 119                                                 implementation. See <literal>ConditionVirtualization=</literal> in
 120                                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 121                                                 for details.
 122                                                 </para>
 123                                         </listitem>
 124                                 </varlistentry>
 125                                 <varlistentry>
 126                                         <term><varname>KernelCommandLine</varname></term>
 127                                         <listitem>
 128                                                 <para>Checks whether a specific kernel command line option is
 129                                                 set (or if prefixed with the exclamation mark unset). See
 130                                                 <literal>ConditionKernelCommandLine=</literal> in
 131                                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 132                                                 for details.
 133                                                 </para>
 134                                         </listitem>
 135                                 </varlistentry>
 136                         </variablelist>
 137
 138                         <para>The <literal>[NetDev]</literal> section accepts the following
 139                         keys:</para>
 140
 141                         <variablelist class='network-directives'>
 142                                 <varlistentry>
 143                                         <term><varname>Name</varname></term>
 144                                         <listitem>
 145                                                 <para>The interface name used when creating the
 146                                                 bridge. This option is compulsory.</para>
 147                                         </listitem>
 148                                 </varlistentry>
 149                                 <varlistentry>
 150                                         <term><varname>Kind</varname></term>
 151                                         <listitem>
 152                                                 <para>The netdev kind. Currently, <literal>bridge</literal>,
 153                                                 <literal>bond</literal> and <literal>vlan</literal>
 154                                                 are supported. This option is compulsory.</para>
 155                                         </listitem>
 156                                 </varlistentry>
 157                         </variablelist>
 158
 159                         <para>The <literal>[VLAN]</literal> section only applies for netdevs of kind <literal>vlan</literal>,
 160                         and accepts the following key:</para>
 161
 162                         <variablelist class='network-directives'>
 163                                 <varlistentry>
 164                                         <term><varname>Id</varname></term>
 165                                         <listitem>
 166                                                 <para>The VLAN ID to use. An integer in the range 0–4094.
 167                                                 This option is compulsory.</para>
 168                                         </listitem>
 169                                 </varlistentry>
 170                         </variablelist>
 171
 172                 </refsect2>
 173
 174                 <refsect2><title>Networks</title>
 175                         <para>Network files must have the extension <filename>.network</filename>;
 176                         other extensions are ignored. Networks are applied to links whenever the links
 177                         appear.</para>
 178
 179                         <para>The network file contains a <literal>[Match]</literal> section,
 180                         which determines if a given network file may be applied to a given device;
 181                         and a <literal>[Network]</literal> section specifying how the device should
 182                         be configured. The first (in lexical order) of the network files that
 183                         matches a given device is applied.</para>
 184
 185                         <para>A network file is said to match a device if each of the entries in the
 186                         <literal>[Match]</literal> section matches, or if the section is empty.
 187                         The following keys are accepted:</para>
 188
 189                         <variablelist class='network-directives'>
 190                                 <varlistentry>
 191                                         <term><varname>MACAddress</varname></term>
 192                                         <listitem>
 193                                                 <para>The hardware address.</para>
 194                                         </listitem>
 195                                 </varlistentry>
 196                                 <varlistentry>
 197                                         <term><varname>Path</varname></term>
 198                                         <listitem>
 199                                                 <para>The persistent path, as exposed by the udev
 200                                                 property <literal>ID_PATH</literal>. May contain shell
 201                                                 style globs.</para>
 202                                         </listitem>
 203                                 </varlistentry>
 204                                 <varlistentry>
 205                                         <term><varname>Driver</varname></term>
 206                                         <listitem>
 207                                                 <para>The driver currently bound to the device, as
 208                                                 exposed by the udev property <literal>DRIVER</literal>
 209                                                 of its parent device.
 210                                                 </para>
 211                                         </listitem>
 212                                 </varlistentry>
 213                                 <varlistentry>
 214                                         <term><varname>Type</varname></term>
 215                                         <listitem>
 216                                                 <para>The device type, as exposed by the udev property
 217                                                 <literal>DEVTYPE</literal>.</para>
 218                                         </listitem>
 219                                 </varlistentry>
 220                                 <varlistentry>
 221                                         <term><varname>Name</varname></term>
 222                                         <listitem>
 223                                                 <para>The device name, as exposed by the udev property
 224                                                 <literal>INTERFACE</literal>. May contain shell style
 225                                                 globs.</para>
 226                                         </listitem>
 227                                 </varlistentry>
 228                                 <varlistentry>
 229                                         <term><varname>Host</varname></term>
 230                                         <listitem>
 231                                                 <para>Matches against the hostname or machine ID of the
 232                                                 host. See <literal>ConditionHost=</literal> in
 233                                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 234                                                 for details.
 235                                                 </para>
 236                                         </listitem>
 237                                 </varlistentry>
 238                                 <varlistentry>
 239                                         <term><varname>Virtualization</varname></term>
 240                                         <listitem>
 241                                                 <para>Checks whether the system is executed in a virtualized
 242                                                 environment and optionally test whether it is a specific
 243                                                 implementation. See <literal>ConditionVirtualization=</literal> in
 244                                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 245                                                 for details.
 246                                                 </para>
 247                                         </listitem>
 248                                 </varlistentry>
 249                                 <varlistentry>
 250                                         <term><varname>KernelCommandLine</varname></term>
 251                                         <listitem>
 252                                                 <para>Checks whether a specific kernel command line option is
 253                                                 set (or if prefixed with the exclamation mark unset). See
 254                                                 <literal>ConditionKernelCommandLine=</literal> in
 255                                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 256                                                 for details.
 257                                                 </para>
 258                                         </listitem>
 259                                 </varlistentry>
 260                         </variablelist>
 261
 262                         <para>The <literal>[Network]</literal> section accepts the following keys:</para>
 263
 264                         <variablelist class='network-directives'>
 265                                 <varlistentry>
 266                                         <term><varname>Description</varname></term>
 267                                         <listitem>
 268                                                 <para>A description of the device. This is only used for
 269                                                 presentation purposes.</para>
 270                                         </listitem>
 271                                 </varlistentry>
 272                                 <varlistentry>
 273                                         <term><varname>DHCP</varname></term>
 274                                         <listitem>
 275                                                 <para>A boolean. When true, enables basic DHCPv4 support.</para>
 276                                         </listitem>
 277                                 </varlistentry>
 278                                 <varlistentry>
 279                                         <term><varname>Address</varname></term>
 280                                         <listitem>
 281                                                 <para>A static IPv4 or IPv6 address and its prefix length,
 282                                                 separated by a <literal>/</literal> character. The format of the address must
 283                                                 be as described in
 284                                                 <citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 285                                                 . This is a short-hand for an [Address] section only containing an Address key (see below).</para>
 286                                         </listitem>
 287                                 </varlistentry>
 288                                 <varlistentry>
 289                                         <term><varname>Gateway</varname></term>
 290                                         <listitem>
 291                                                 <para>The gateway address, which must be in the format described in
 292                                                 <citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 293                                                 . This is a short-hand for a [Route] section only containing a Gateway key.</para>
 294                                         </listitem>
 295                                 </varlistentry>
 296                                 <varlistentry>
 297                                         <term><varname>DNS</varname></term>
 298                                         <listitem>
 299                                                 <para>A DNS server address, which must be in the format described in
 300                                                 <citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 301                                                 .</para>
 302                                         </listitem>
 303                                 </varlistentry>
 304                                 <varlistentry>
 305                                         <term><varname>Bridge</varname></term>
 306                                         <listitem>
 307                                                 <para>The name of the bridge to add the link to.</para>
 308                                         </listitem>
 309                                 </varlistentry>
 310                                 <varlistentry>
 311                                         <term><varname>Bond</varname></term>
 312                                         <listitem>
 313                                                 <para>The name of the bond to add the link to.</para>
 314                                         </listitem>
 315                                 </varlistentry>
 316                                 <varlistentry>
 317                                         <term><varname>VLAN</varname></term>
 318                                         <listitem>
 319                                                 <para>The name of a VLAN to create on the link. This option
 320                                                 may be specified more than once.</para>
 321                                         </listitem>
 322                                 </varlistentry>
 323                         </variablelist>
 324
 325                         <para>The <literal>[Address]</literal> section accepts the following keys:</para>
 326
 327                         <variablelist class='network-directives'>
 328                                 <varlistentry>
 329                                         <term><varname>Address</varname></term>
 330                                         <listitem>
 331                                                 <para>As in the <literal>[Network]</literal> section. This key is mandatory.</para>
 332                                         </listitem>
 333                                 </varlistentry>
 334                                 <varlistentry>
 335                                         <term><varname>Broadcast</varname></term>
 336                                         <listitem>
 337                                                 <para>The broadcast address, which must be in the format described in
 338                                                 <citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 339                                                 . This key only applies to IPv4 addresses. If it is not given, it is
 340                                                 derived from the <literal>Address</literal> key.</para>
 341                                         </listitem>
 342                                 </varlistentry>
 343                                 <varlistentry>
 344                                         <term><varname>Label</varname></term>
 345                                         <listitem>
 346                                                 <para>An address label.</para>
 347                                         </listitem>
 348                                 </varlistentry>
 349                         </variablelist>
 350
 351                         <para>The <literal>[Route]</literal> section accepts the following keys:</para>
 352
 353                         <variablelist class='network-directives'>
 354                                 <varlistentry>
 355                                         <term><varname>Gateway</varname></term>
 356                                         <listitem>
 357                                                 <para>As in the <literal>[Network]</literal> section. This key is mandatory.</para>
 358                                         </listitem>
 359                                 </varlistentry>
 360                                 <varlistentry>
 361                                         <term><varname>Destination</varname></term>
 362                                         <listitem>
 363                                                 <para>The destination prefix of the route. Possibly followed by a slash and the
 364                                                 prefixlength, if ommitted a full-length host route is assumed.</para>
 365                                         </listitem>
 366                                 </varlistentry>
 367                         </variablelist>
 368
 369                         <para>The <literal>[DHCPv4]</literal> section accepts the following keys:</para>
 370
 371                         <variablelist class='network-directives'>
 372                                 <varlistentry>
 373                                         <term><varname>UseDNS</varname></term>
 374                                         <listitem>
 375                                                 <para>When true (the default), the DNS servers received from the DHCP server will
 376                                                 be used and take precedence over any statically configured ones.</para>
 377                                         </listitem>
 378                                 </varlistentry>
 379                                 <varlistentry>
 380                                         <term><varname>UseMTU</varname></term>
 381                                         <listitem>
 382                                                 <para>When true, the interface maximum transmission unit from the DHCP server will
 383                                                 be used on the current link. Defaults to false.</para>
 384                                         </listitem>
 385                                 </varlistentry>
 386                                 <varlistentry>
 387                                         <term><varname>UseHostname</varname></term>
 388                                         <listitem>
 389                                                 <para>When true (the default), the hostname received from the DHCP server
 390                                                 will be used as the transient hostname.</para>
 391                                         </listitem>
 392                                 </varlistentry>
 393                                 <varlistentry>
 394                                         <term><varname>CriticalConnection</varname></term>
 395                                         <listitem>
 396                                                 <para>When true, the connection will never be torn down even if the DHCP lease
 397                                                 expires. This is contrary to the DHCP specification, but may be the best choice
 398                                                 if, say, the root filesystem relies on this connection. Defaults to false.</para>
 399                                         </listitem>
 400                                 </varlistentry>
 401                        </variablelist>
 402
 403                 </refsect2>
 404         </refsect1>
 405
 406         <refsect1>
 407                 <title>See Also</title>
 408                 <para>
 409                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 410                         <citerefentry><refentrytitle>udev</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
 411                 </para>
 412         </refsect1>
 413
 414 </refentry>