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">
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   8   Copyright 2013 Tom Gundersen
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  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>Network configurations applied before networkd is started
  65                 are not removed, and configuration applied by networkd are not
  66                 removed when networkd exits. This ensures restarting networkd
  67                 does not cut the network connection, and, in particular, that
  68                 it is safe to transition between the initrd and the real root,
  69                 and back.</para>
  70         </refsect1>
  71
  72         <refsect1><title>Configuration Files</title>
  73                 <para>The configuration files are read from the files located in the
  74                 system network directory <filename>/usr/lib/systemd/network</filename>,
  75                 the volatile runtime network directory
  76                 <filename>/run/systemd/network</filename> and the local administration
  77                 network directory <filename>/etc/systemd/network</filename>.
  78                 All configuration files are collectively sorted and processed in lexical order,
  79                 regardless of the directories in which they live. However, files with
  80                 identical filenames replace each other. Files in
  81                 <filename>/etc</filename> have the highest priority, files in
  82                 <filename>/run</filename> take precedence over files with the same
  83                 name in <filename>/usr/lib</filename>. This can be used to override a
  84                 system-supplied configuration file with a local file if needed; a symlink in
  85                 <filename>/etc</filename> with the same name as a configuration file in
  86                 <filename>/usr/lib</filename>, pointing to <filename>/dev/null</filename>,
  87                 disables the configuration file entirely.</para>
  88
  89                 <refsect2><title>Virtual Network Devices</title>
  90                         <para>Netdev files must have the extension <filename>.netdev</filename>;
  91                         other extensions are ignored. Virtual network devices are created as soon
  92                         as networkd is started.</para>
  93
  94                         <para>The <literal>[Netdev]</literal> section accepts the following
  95                         keys:</para>
  96
  97                         <variablelist class='network-directives'>
  98                                 <varlistentry>
  99                                         <term><varname>Name</varname></term>
 100                                         <listitem>
 101                                                 <para>The interface name used when creating the
 102                                                 bridge. This option is compulsory.</para>
 103                                         </listitem>
 104                                 </varlistentry>
 105                                 <varlistentry>
 106                                         <term><varname>Kind</varname></term>
 107                                         <listitem>
 108                                                 <para>The netdev kind. Currently, 'bridge', 'bond' and 'vlan'
 109                                                 are supported. This option is compulsory.</para>
 110                                         </listitem>
 111                                 </varlistentry>
 112                         </variablelist>
 113
 114                         <para>The <literal>[VLAN]</literal> section only applies for netdevs of kind 'vlan',
 115                         and accepts the following keys:</para>
 116
 117                         <variablelist class='network-directives'>
 118                                 <varlistentry>
 119                                         <term><varname>Id</varname></term>
 120                                         <listitem>
 121                                                 <para>The VLAN ID to use. This option is compulsory.</para>
 122                                         </listitem>
 123                                 </varlistentry>
 124                         </variablelist>
 125
 126                 </refsect2>
 127
 128                 <refsect2><title>Networks</title>
 129                         <para>Network files must have the extension <filename>.network</filename>;
 130                         other extensions are ignored. Networks are applied to links whenever the links
 131                         appear.</para>
 132
 133                         <para>The network file contains a <literal>[Match]</literal> section,
 134                         which determines if a given network file may be applied to a given device;
 135                         and a <literal>[Network]</literal> section specifying how the device should
 136                         be configured. The first (in lexical order) of the network files that
 137                         matches a given device is applied.</para>
 138
 139                         <para>A network file is said to match a device if each of the entries in the
 140                         <literal>[Match]</literal> section matches, or if the section is empty.
 141                         The following keys are accepted:</para>
 142
 143                         <variablelist class='network-directives'>
 144                                 <varlistentry>
 145                                         <term><varname>MACAddress</varname></term>
 146                                         <listitem>
 147                                                 <para>The hardware address.</para>
 148                                         </listitem>
 149                                 </varlistentry>
 150                                 <varlistentry>
 151                                         <term><varname>Path</varname></term>
 152                                         <listitem>
 153                                                 <para>The persistent path, as exposed by the udev
 154                                                 property <literal>ID_PATH</literal>.</para>
 155                                         </listitem>
 156                                 </varlistentry>
 157                                 <varlistentry>
 158                                         <term><varname>Driver</varname></term>
 159                                         <listitem>
 160                                                 <para>The driver currently bound to the device, as
 161                                                 exposed by the udev property <literal>DRIVER</literal>.
 162                                                 </para>
 163                                         </listitem>
 164                                 </varlistentry>
 165                                 <varlistentry>
 166                                         <term><varname>Type</varname></term>
 167                                         <listitem>
 168                                                 <para>The device type, as exposed by the udev property
 169                                                 <literal>DEVTYPE</literal>.</para>
 170                                         </listitem>
 171                                 </varlistentry>
 172                                 <varlistentry>
 173                                         <term><varname>Name</varname></term>
 174                                         <listitem>
 175                                                 <para>The device name, as exposed by the udev property
 176                                                 <literal>INTERFACE</literal>.</para>
 177                                         </listitem>
 178                                 </varlistentry>
 179                         </variablelist>
 180
 181                         <para>The <literal>[Network]</literal> section accepts the following keys:</para>
 182
 183                         <variablelist class='network-directives'>
 184                                 <varlistentry>
 185                                         <term><varname>Description</varname></term>
 186                                         <listitem>
 187                                                 <para>A description of the device. This is only used for
 188                                                 presentation purposes.</para>
 189                                         </listitem>
 190                                 </varlistentry>
 191                                 <varlistentry>
 192                                         <term><varname>DHCP</varname></term>
 193                                         <listitem>
 194                                                 <para>A boolean. When true enables basic DHCPv4 support.</para>
 195                                         </listitem>
 196                                 </varlistentry>
 197                                 <varlistentry>
 198                                         <term><varname>Address</varname></term>
 199                                         <listitem>
 200                                                 <para>A static IPv4 or IPv6 address and its prefix length,
 201                                                 separated by a '/' character. The format of the address must
 202                                                 be as described in
 203                                                 <citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 204                                                 . This is a short-hand for an [Address] section only containing an Address key (see below).</para>
 205                                         </listitem>
 206                                 </varlistentry>
 207                                 <varlistentry>
 208                                         <term><varname>Gateway</varname></term>
 209                                         <listitem>
 210                                                 <para>The gateway address, which must be in the format described in
 211                                                 <citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 212                                                 . This is a short-hand for a [Route] section only containing a Gateway key.</para>
 213                                         </listitem>
 214                                 </varlistentry>
 215                                 <varlistentry>
 216                                         <term><varname>DNS</varname></term>
 217                                         <listitem>
 218                                                 <para>A DNS server address, which must be in the format described in
 219                                                 <citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 220                                                 .</para>
 221                                         </listitem>
 222                                 </varlistentry>
 223                                 <varlistentry>
 224                                         <term><varname>Bridge</varname></term>
 225                                         <listitem>
 226                                                 <para>The name of the bridge to add the configured link to.</para>
 227                                         </listitem>
 228                                 </varlistentry>
 229                                 <varlistentry>
 230                                         <term><varname>Bond</varname></term>
 231                                         <listitem>
 232                                                 <para>The name of the bond to add the configured link to.</para>
 233                                         </listitem>
 234                                 </varlistentry>
 235                         </variablelist>
 236
 237                         <para>The <literal>[Address]</literal> section accepts the following keys:</para>
 238
 239                         <variablelist class='network-directives'>
 240                                 <varlistentry>
 241                                         <term><varname>Address</varname></term>
 242                                         <listitem>
 243                                                 <para>As in the <literal>[Network]</literal> section. This key is mandatory.</para>
 244                                         </listitem>
 245                                 </varlistentry>
 246                                 <varlistentry>
 247                                         <term><varname>Label</varname></term>
 248                                         <listitem>
 249                                                 <para>An address label.</para>
 250                                         </listitem>
 251                                 </varlistentry>
 252                         </variablelist>
 253
 254                         <para>The <literal>[Route]</literal> section accepts the following keys:</para>
 255
 256                         <variablelist class='network-directives'>
 257                                 <varlistentry>
 258                                         <term><varname>Gateway</varname></term>
 259                                         <listitem>
 260                                                 <para>As in the <literal>[Network]</literal> section. This key is mandatory.</para>
 261                                         </listitem>
 262                                 </varlistentry>
 263                                 <varlistentry>
 264                                         <term><varname>Destination</varname></term>
 265                                         <listitem>
 266                                                 <para>The destination prefix of the route. Possibly followed by a slash and the
 267                                                 prefixlength, if ommitted a full-length host route is assumed.</para>
 268                                         </listitem>
 269                                 </varlistentry>
 270                         </variablelist>
 271
 272                         <para>The <literal>[DHCPv4]</literal> section accepts the following keys:</para>
 273
 274                         <variablelist class='network-directives'>
 275                                 <varlistentry>
 276                                         <term><varname>UseDNS</varname></term>
 277                                         <listitem>
 278                                                 <para>When true (the default) the DNS servers received from the DHCP server will
 279                                                 be used, and take precedence over any statically configured ones.</para>
 280                                         </listitem>
 281                                 </varlistentry>
 282                                 <varlistentry>
 283                                         <term><varname>UseMTU</varname></term>
 284                                         <listitem>
 285                                                 <para>When true the interface maximum transmission unit from the DHCP server will
 286                                                 be used on the current link. Defaults to false.</para>
 287                                         </listitem>
 288                                 </varlistentry>
 289                                 <varlistentry>
 290                                         <term><varname>UseHostname</varname></term>
 291                                         <listitem>
 292                                                 <para>When true (the default) the hostname received from the DHCP server
 293                                                 will be used as the transient hostname.</para>
 294                                         </listitem>
 295                                 </varlistentry>
 296                                 <varlistentry>
 297                                         <term><varname>CriticalConnection</varname></term>
 298                                         <listitem>
 299                                                 <para>When true the connection will never be torn down even if the DHCP lease
 300                                                 expires. This is contrary to the DHCP specification, but may be the best choice
 301                                                 if, say, the root filesystem relies on this connection. Defaults to false.</para>
 302                                         </listitem>
 303                                 </varlistentry>
 304                        </variablelist>
 305
 306                 </refsect2>
 307         </refsect1>
 308
 309         <refsect1>
 310                 <title>See Also</title>
 311                 <para>
 312                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 313                         <citerefentry><refentrytitle>udev</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
 314                 </para>
 315         </refsect1>
 316
 317 </refentry>