man/systemd-networkd.service.xml

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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>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                 is 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                                 <varlistentry>
 137                                         <term><varname>Architecture=</varname></term>
 138                                         <listitem>
 139                                                 <para>Checks whether the system is running on a specific
 140                                                 architecture. See <literal>ConditionArchitecture=</literal> in
 141                                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 142                                                 for details.
 143                                                 </para>
 144                                         </listitem>
 145                                 </varlistentry>
 146                         </variablelist>
 147
 148                         <para>The <literal>[NetDev]</literal> section accepts the following
 149                         keys:</para>
 150
 151                         <variablelist class='network-directives'>
 152                                 <varlistentry>
 153                                         <term><varname>Name=</varname></term>
 154                                         <listitem>
 155                                                 <para>The interface name used when creating the
 156                                                 netdev. This option is compulsory.</para>
 157                                         </listitem>
 158                                 </varlistentry>
 159                                 <varlistentry>
 160                                         <term><varname>Kind=</varname></term>
 161                                         <listitem>
 162                                                 <para>The netdev kind. Currently, <literal>bridge</literal>,
 163                                                 <literal>bond</literal> and <literal>vlan</literal>
 164                                                 are supported. This option is compulsory.</para>
 165                                         </listitem>
 166                                 </varlistentry>
 167                         </variablelist>
 168
 169                         <para>The <literal>[VLAN]</literal> section only applies for netdevs of kind <literal>vlan</literal>,
 170                         and accepts the following key:</para>
 171
 172                         <variablelist class='network-directives'>
 173                                 <varlistentry>
 174                                         <term><varname>Id=</varname></term>
 175                                         <listitem>
 176                                                 <para>The VLAN ID to use. An integer in the range 0–4094.
 177                                                 This option is compulsory.</para>
 178                                         </listitem>
 179                                 </varlistentry>
 180                         </variablelist>
 181
 182                 </refsect2>
 183
 184                 <refsect2><title>Networks</title>
 185                         <para>Network files must have the extension <filename>.network</filename>;
 186                         other extensions are ignored. Networks are applied to links whenever the links
 187                         appear.</para>
 188
 189                         <para>The network file contains a <literal>[Match]</literal> section,
 190                         which determines if a given network file may be applied to a given device;
 191                         and a <literal>[Network]</literal> section specifying how the device should
 192                         be configured. The first (in lexical order) of the network files that
 193                         matches a given device is applied.</para>
 194
 195                         <para>A network file is said to match a device if each of the entries in the
 196                         <literal>[Match]</literal> section matches, or if the section is empty.
 197                         The following keys are accepted:</para>
 198
 199                         <variablelist class='network-directives'>
 200                                 <varlistentry>
 201                                         <term><varname>MACAddress=</varname></term>
 202                                         <listitem>
 203                                                 <para>The hardware address.</para>
 204                                         </listitem>
 205                                 </varlistentry>
 206                                 <varlistentry>
 207                                         <term><varname>Path=</varname></term>
 208                                         <listitem>
 209                                                 <para>The persistent path, as exposed by the udev
 210                                                 property <literal>ID_PATH</literal>. May contain shell
 211                                                 style globs.</para>
 212                                         </listitem>
 213                                 </varlistentry>
 214                                 <varlistentry>
 215                                         <term><varname>Driver=</varname></term>
 216                                         <listitem>
 217                                                 <para>The driver currently bound to the device, as
 218                                                 exposed by the udev property <literal>DRIVER</literal>
 219                                                 of its parent device, or if that is not set the driver
 220                                                 as exposed by <literal>ethtool -i</literal> of the
 221                                                 device itself.</para>
 222                                         </listitem>
 223                                 </varlistentry>
 224                                 <varlistentry>
 225                                         <term><varname>Type=</varname></term>
 226                                         <listitem>
 227                                                 <para>The device type, as exposed by the udev property
 228                                                 <literal>DEVTYPE</literal>.</para>
 229                                         </listitem>
 230                                 </varlistentry>
 231                                 <varlistentry>
 232                                         <term><varname>Name=</varname></term>
 233                                         <listitem>
 234                                                 <para>The device name, as exposed by the udev property
 235                                                 <literal>INTERFACE</literal>. May contain shell style
 236                                                 globs.</para>
 237                                         </listitem>
 238                                 </varlistentry>
 239                                 <varlistentry>
 240                                         <term><varname>Host=</varname></term>
 241                                         <listitem>
 242                                                 <para>Matches against the hostname or machine ID of the
 243                                                 host. See <literal>ConditionHost=</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>Virtualization=</varname></term>
 251                                         <listitem>
 252                                                 <para>Checks whether the system is executed in a virtualized
 253                                                 environment and optionally test whether it is a specific
 254                                                 implementation. See <literal>ConditionVirtualization=</literal> in
 255                                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 256                                                 for details.
 257                                                 </para>
 258                                         </listitem>
 259                                 </varlistentry>
 260                                 <varlistentry>
 261                                         <term><varname>KernelCommandLine=</varname></term>
 262                                         <listitem>
 263                                                 <para>Checks whether a specific kernel command line option is
 264                                                 set (or if prefixed with the exclamation mark unset). See
 265                                                 <literal>ConditionKernelCommandLine=</literal> in
 266                                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 267                                                 for details.
 268                                                 </para>
 269                                         </listitem>
 270                                 </varlistentry>
 271                                 <varlistentry>
 272                                         <term><varname>Architecture=</varname></term>
 273                                         <listitem>
 274                                                 <para>Checks whether the system is running on a specific
 275                                                 architecture. See <literal>ConditionArchitecture=</literal> in
 276                                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 277                                                 for details.
 278                                                 </para>
 279                                         </listitem>
 280                                 </varlistentry>
 281                         </variablelist>
 282
 283                         <para>The <literal>[Network]</literal> section accepts the following keys:</para>
 284
 285                         <variablelist class='network-directives'>
 286                                 <varlistentry>
 287                                         <term><varname>Description=</varname></term>
 288                                         <listitem>
 289                                                 <para>A description of the device. This is only used for
 290                                                 presentation purposes.</para>
 291                                         </listitem>
 292                                 </varlistentry>
 293                                 <varlistentry>
 294                                         <term><varname>DHCP=</varname></term>
 295                                         <listitem>
 296                                                 <para>A boolean. When true, enables basic DHCPv4 support.</para>
 297                                         </listitem>
 298                                 </varlistentry>
 299                                 <varlistentry>
 300                                         <term><varname>Address=</varname></term>
 301                                         <listitem>
 302                                                 <para>A static IPv4 or IPv6 address and its prefix length,
 303                                                 separated by a <literal>/</literal> character. The format of the address must
 304                                                 be as described in
 305                                                 <citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 306                                                 . This is a short-hand for an [Address] section only containing an Address key (see below).</para>
 307                                         </listitem>
 308                                 </varlistentry>
 309                                 <varlistentry>
 310                                         <term><varname>Gateway=</varname></term>
 311                                         <listitem>
 312                                                 <para>The gateway address, which must be in the format described in
 313                                                 <citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 314                                                 . This is a short-hand for a [Route] section only containing a Gateway key.</para>
 315                                         </listitem>
 316                                 </varlistentry>
 317                                 <varlistentry>
 318                                         <term><varname>DNS=</varname></term>
 319                                         <listitem>
 320                                                 <para>A DNS server address, which must be in the format described in
 321                                                 <citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 322                                                 .</para>
 323                                         </listitem>
 324                                 </varlistentry>
 325                                 <varlistentry>
 326                                         <term><varname>Bridge=</varname></term>
 327                                         <listitem>
 328                                                 <para>The name of the bridge to add the link to.</para>
 329                                         </listitem>
 330                                 </varlistentry>
 331                                 <varlistentry>
 332                                         <term><varname>Bond=</varname></term>
 333                                         <listitem>
 334                                                 <para>The name of the bond to add the link to.</para>
 335                                         </listitem>
 336                                 </varlistentry>
 337                                 <varlistentry>
 338                                         <term><varname>VLAN=</varname></term>
 339                                         <listitem>
 340                                                 <para>The name of a VLAN to create on the link. This option
 341                                                 may be specified more than once.</para>
 342                                         </listitem>
 343                                 </varlistentry>
 344                         </variablelist>
 345
 346                         <para>The <literal>[Address]</literal> section accepts the following keys:</para>
 347
 348                         <variablelist class='network-directives'>
 349                                 <varlistentry>
 350                                         <term><varname>Address=</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>Broadcast=</varname></term>
 357                                         <listitem>
 358                                                 <para>The broadcast address, which must be in the format described in
 359                                                 <citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 360                                                 . This key only applies to IPv4 addresses. If it is not given, it is
 361                                                 derived from the <literal>Address</literal> key.</para>
 362                                         </listitem>
 363                                 </varlistentry>
 364                                 <varlistentry>
 365                                         <term><varname>Label=</varname></term>
 366                                         <listitem>
 367                                                 <para>An address label.</para>
 368                                         </listitem>
 369                                 </varlistentry>
 370                         </variablelist>
 371
 372                         <para>The <literal>[Route]</literal> section accepts the following keys:</para>
 373
 374                         <variablelist class='network-directives'>
 375                                 <varlistentry>
 376                                         <term><varname>Gateway=</varname></term>
 377                                         <listitem>
 378                                                 <para>As in the <literal>[Network]</literal> section. This key is mandatory.</para>
 379                                         </listitem>
 380                                 </varlistentry>
 381                                 <varlistentry>
 382                                         <term><varname>Destination=</varname></term>
 383                                         <listitem>
 384                                                 <para>The destination prefix of the route. Possibly followed by a slash and the
 385                                                 prefixlength, if ommitted a full-length host route is assumed.</para>
 386                                         </listitem>
 387                                 </varlistentry>
 388                         </variablelist>
 389
 390                         <para>The <literal>[DHCPv4]</literal> section accepts the following keys:</para>
 391
 392                         <variablelist class='network-directives'>
 393                                 <varlistentry>
 394                                         <term><varname>UseDNS=</varname></term>
 395                                         <listitem>
 396                                                 <para>When true (the default), the DNS servers received from the DHCP server will
 397                                                 be used and take precedence over any statically configured ones.</para>
 398                                         </listitem>
 399                                 </varlistentry>
 400                                 <varlistentry>
 401                                         <term><varname>UseMTU=</varname></term>
 402                                         <listitem>
 403                                                 <para>When true, the interface maximum transmission unit from the DHCP server will
 404                                                 be used on the current link. Defaults to false.</para>
 405                                         </listitem>
 406                                 </varlistentry>
 407                                 <varlistentry>
 408                                         <term><varname>UseHostname=</varname></term>
 409                                         <listitem>
 410                                                 <para>When true (the default), the hostname received from the DHCP server
 411                                                 will be used as the transient hostname.</para>
 412                                         </listitem>
 413                                 </varlistentry>
 414                                 <varlistentry>
 415                                         <term><varname>CriticalConnection=</varname></term>
 416                                         <listitem>
 417                                                 <para>When true, the connection will never be torn down even if the DHCP lease
 418                                                 expires. This is contrary to the DHCP specification, but may be the best choice
 419                                                 if, say, the root filesystem relies on this connection. Defaults to false.</para>
 420                                         </listitem>
 421                                 </varlistentry>
 422                        </variablelist>
 423
 424                 </refsect2>
 425         </refsect1>
 426
 427         <refsect1>
 428                 <title>See Also</title>
 429                 <para>
 430                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 431                         <citerefentry><refentrytitle>udev</refentrytitle><manvolnum>7</manvolnum></citerefentry>
 432                 </para>
 433         </refsect1>
 434
 435 </refentry>