man/systemd.network.xml

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  23
  24 <refentry id="systemd.network" conditional='ENABLE_NETWORKD'>
  25
  26         <refentryinfo>
  27                 <title>systemd.network</title>
  28                 <productname>systemd</productname>
  29
  30                 <authorgroup>
  31                         <author>
  32                                 <contrib>Developer</contrib>
  33                                 <firstname>Tom</firstname>
  34                                 <surname>Gundersen</surname>
  35                                 <email>teg@jklm.no</email>
  36                         </author>
  37                 </authorgroup>
  38         </refentryinfo>
  39
  40         <refmeta>
  41                 <refentrytitle>systemd.network</refentrytitle>
  42                 <manvolnum>5</manvolnum>
  43         </refmeta>
  44
  45         <refnamediv>
  46                 <refname>systemd.network</refname>
  47                 <refpurpose>Network configuration</refpurpose>
  48         </refnamediv>
  49
  50         <refsynopsisdiv>
  51                 <para><filename><replaceable>network</replaceable>.network</filename></para>
  52         </refsynopsisdiv>
  53
  54         <refsect1>
  55                 <title>Description</title>
  56
  57                 <para>Network setup is performed by
  58                 <citerefentry><refentrytitle>systemd-networkd</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
  59                 </para>
  60
  61                 <para>Network files must have the extension <filename>.network</filename>;
  62                 other extensions are ignored. Networks are applied to links whenever the links
  63                 appear.</para>
  64
  65                 <para>The <filename>.network</filename> files are read from the files located in the
  66                 system network directory <filename>/usr/lib/systemd/network</filename>,
  67                 the volatile runtime network directory
  68                 <filename>/run/systemd/network</filename> and the local administration
  69                 network directory <filename>/etc/systemd/network</filename>.
  70                 All configuration files are collectively sorted and processed in lexical order,
  71                 regardless of the directories in which they live. However, files with
  72                 identical filenames replace each other. Files in
  73                 <filename>/etc</filename> have the highest priority, files in
  74                 <filename>/run</filename> take precedence over files with the same
  75                 name in <filename>/usr/lib</filename>. This can be used to override a
  76                 system-supplied configuration file with a local file if needed; a symlink in
  77                 <filename>/etc</filename> with the same name as a configuration file in
  78                 <filename>/usr/lib</filename>, pointing to <filename>/dev/null</filename>,
  79                 disables the configuration file entirely.</para>
  80
  81         </refsect1>
  82
  83         <refsect1>
  84                 <title>[Match] Section Options</title>
  85
  86                         <para>The network file contains a <literal>[Match]</literal> section,
  87                         which determines if a given network file may be applied to a given device;
  88                         and a <literal>[Network]</literal> section specifying how the device should
  89                         be configured. The first (in lexical order) of the network files that
  90                         matches a given device is applied.</para>
  91
  92                         <para>A network file is said to match a device if each of the entries in the
  93                         <literal>[Match]</literal> section matches, or if the section is empty.
  94                         The following keys are accepted:</para>
  95
  96                         <variablelist class='network-directives'>
  97                                 <varlistentry>
  98                                         <term><varname>MACAddress=</varname></term>
  99                                         <listitem>
 100                                                 <para>The hardware address.</para>
 101                                         </listitem>
 102                                 </varlistentry>
 103                                 <varlistentry>
 104                                         <term><varname>Path=</varname></term>
 105                                         <listitem>
 106                                                 <para>The persistent path, as exposed by the udev
 107                                                 property <literal>ID_PATH</literal>. May contain shell
 108                                                 style globs.</para>
 109                                         </listitem>
 110                                 </varlistentry>
 111                                 <varlistentry>
 112                                         <term><varname>Driver=</varname></term>
 113                                         <listitem>
 114                                                 <para>The driver currently bound to the device, as
 115                                                 exposed by the udev property <literal>DRIVER</literal>
 116                                                 of its parent device, or if that is not set the driver
 117                                                 as exposed by <literal>ethtool -i</literal> of the
 118                                                 device itself.</para>
 119                                         </listitem>
 120                                 </varlistentry>
 121                                 <varlistentry>
 122                                         <term><varname>Type=</varname></term>
 123                                         <listitem>
 124                                                 <para>The device type, as exposed by the udev property
 125                                                 <literal>DEVTYPE</literal>.</para>
 126                                         </listitem>
 127                                 </varlistentry>
 128                                 <varlistentry>
 129                                         <term><varname>Name=</varname></term>
 130                                         <listitem>
 131                                                 <para>The device name, as exposed by the udev property
 132                                                 <literal>INTERFACE</literal>. May contain shell style
 133                                                 globs.</para>
 134                                         </listitem>
 135                                 </varlistentry>
 136                                 <varlistentry>
 137                                         <term><varname>Host=</varname></term>
 138                                         <listitem>
 139                                                 <para>Matches against the hostname or machine ID of the
 140                                                 host. See <literal>ConditionHost=</literal> in
 141                                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 142                                                 for details.
 143                                                 </para>
 144                                         </listitem>
 145                                 </varlistentry>
 146                                 <varlistentry>
 147                                         <term><varname>Virtualization=</varname></term>
 148                                         <listitem>
 149                                                 <para>Checks whether the system is executed in a virtualized
 150                                                 environment and optionally test whether it is a specific
 151                                                 implementation. See <literal>ConditionVirtualization=</literal> in
 152                                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 153                                                 for details.
 154                                                 </para>
 155                                         </listitem>
 156                                 </varlistentry>
 157                                 <varlistentry>
 158                                         <term><varname>KernelCommandLine=</varname></term>
 159                                         <listitem>
 160                                                 <para>Checks whether a specific kernel command line option is
 161                                                 set (or if prefixed with the exclamation mark unset). See
 162                                                 <literal>ConditionKernelCommandLine=</literal> in
 163                                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 164                                                 for details.
 165                                                 </para>
 166                                         </listitem>
 167                                 </varlistentry>
 168                                 <varlistentry>
 169                                         <term><varname>Architecture=</varname></term>
 170                                         <listitem>
 171                                                 <para>Checks whether the system is running on a specific
 172                                                 architecture. See <literal>ConditionArchitecture=</literal> in
 173                                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 174                                                 for details.
 175                                                 </para>
 176                                         </listitem>
 177                                 </varlistentry>
 178                         </variablelist>
 179
 180         </refsect1>
 181
 182         <refsect1>
 183                 <title>[Link] Section Options</title>
 184
 185                 <para> The <literal>[Link]</literal> section accepts the following keys:</para>
 186
 187                 <variablelist class='network-directives'>
 188                         <varlistentry>
 189                                 <term><varname>MACAddress=</varname></term>
 190                                 <listitem>
 191                                         <para>The hardware address.</para>
 192                                 </listitem>
 193                         </varlistentry>
 194                         <varlistentry>
 195                                 <term><varname>MTUBytes=</varname></term>
 196                                 <listitem>
 197                                         <para>The maximum transmission unit in bytes to
 198                                         set for the device. The usual suffixes K, M, G,
 199                                         are supported and are understood to the base of
 200                                         1024.</para>
 201                                 </listitem>
 202                         </varlistentry>
 203                 </variablelist>
 204         </refsect1>
 205
 206         <refsect1>
 207                 <title>[Network] Section Options</title>
 208
 209                         <para>The <literal>[Network]</literal> section accepts the following keys:</para>
 210
 211                         <variablelist class='network-directives'>
 212                                 <varlistentry>
 213                                         <term><varname>Description=</varname></term>
 214                                         <listitem>
 215                                                 <para>A description of the device. This is only used for
 216                                                 presentation purposes.</para>
 217                                         </listitem>
 218                                 </varlistentry>
 219                                 <varlistentry>
 220                                         <term><varname>DHCP=</varname></term>
 221                                         <listitem>
 222                                                 <para>Enables DHCPv4 and/or DHCPv6 support. Accepts
 223                                                 <literal>both</literal>, <literal>none</literal>,
 224                                                 <literal>v4</literal> or <literal>v6</literal>.</para>
 225                                         </listitem>
 226                                 </varlistentry>
 227                                 <varlistentry>
 228                                         <term><varname>DHCPServer=</varname></term>
 229                                         <listitem>
 230                                                 <para>A boolean. Enables a basic DHCPv4 server on the
 231                                                 device. Mostly useful for handing out leases to container
 232                                                 instances.</para>
 233                                         </listitem>
 234                                 </varlistentry>
 235                                 <varlistentry>
 236                                         <term><varname>IPv4LL=</varname></term>
 237                                         <listitem>
 238                                                 <para>A boolean. When true, enables IPv4 link-local support.
 239                                                 </para>
 240                                         </listitem>
 241                                 </varlistentry>
 242                                 <varlistentry>
 243                                         <term><varname>IPv4LLRoute=</varname></term>
 244                                         <listitem>
 245                                                 <para>A boolean. When true, sets up the route needed for
 246                                                 non-IPv4LL hosts to communicate with IPv4LL-only hosts. Defaults
 247                                                 to false.
 248                                                 </para>
 249                                         </listitem>
 250                                 </varlistentry>
 251                                 <varlistentry>
 252                                         <term><varname>LLMNR=</varname></term>
 253                                         <listitem>
 254                                                 <para>A boolean or <literal>resolve</literal>. When true, enables
 255                                                 Link-Local Multicast Name Resolution on the link, when set to
 256                                                 <literal>resolve</literal> only resolution is enabled, but not
 257                                                 announcement. Defaults to true.</para>
 258                                         </listitem>
 259                                 </varlistentry>
 260                                 <varlistentry>
 261                                         <term><varname>Address=</varname></term>
 262                                         <listitem>
 263                                                 <para>A static IPv4 or IPv6 address and its prefix length,
 264                                                 separated by a <literal>/</literal> character. Specify this
 265                                                 key more than once to configure several addresses.
 266                                                 The format of the address must be as described in
 267                                                 <citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
 268                                                 This is a short-hand for an [Address] section only containing
 269                                                 an Address key (see below). This option may be specified
 270                                                 more than once.
 271                                                 </para>
 272
 273                                                 <para>If the specified
 274                                                 address is 0.0.0.0
 275                                                 (for IPv4) or [::]
 276                                                 (for IPv6), a new
 277                                                 address range of the
 278                                                 requested size is
 279                                                 automatically
 280                                                 allocated from a
 281                                                 system-wide pool of
 282                                                 unused ranges. The
 283                                                 allocated range is
 284                                                 checked against all
 285                                                 current network
 286                                                 interfaces and all
 287                                                 known network
 288                                                 configuration files to
 289                                                 avoid address range
 290                                                 conflicts. The default
 291                                                 system-wide pool
 292                                                 consists of
 293                                                 192.168.0.0/16,
 294                                                 172.16.0.0/12 and
 295                                                 10.0.0.0/8 for IPv4,
 296                                                 and fc00::/7 for
 297                                                 IPv6. This
 298                                                 functionality is
 299                                                 useful to manage a
 300                                                 large number of
 301                                                 dynamically created
 302                                                 network interfaces
 303                                                 with the same network
 304                                                 configuration and
 305                                                 automatic address
 306                                                 range
 307                                                 assignment.</para>
 308
 309                                         </listitem>
 310                                 </varlistentry>
 311                                 <varlistentry>
 312                                         <term><varname>Gateway=</varname></term>
 313                                         <listitem>
 314                                                 <para>The gateway address, which must be in the format described in
 315                                                 <citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
 316                                                 This is a short-hand for a [Route] section only containing a Gateway
 317                                                 key. This option may be specified more than once.</para>
 318                                         </listitem>
 319                                 </varlistentry>
 320                                 <varlistentry>
 321                                         <term><varname>DNS=</varname></term>
 322                                         <listitem>
 323                                                 <para>A DNS server address, which must be in the format described in
 324                                                 <citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
 325                                                 This option may be specified more than once.</para>
 326                                         </listitem>
 327                                 </varlistentry>
 328                                 <varlistentry>
 329                                         <term><varname>Domains=</varname></term>
 330                                         <listitem>
 331                                                 <para>The domains used for DNS resolution over this link.</para>
 332                                         </listitem>
 333                                 </varlistentry>
 334                                 <varlistentry>
 335                                         <term><varname>NTP=</varname></term>
 336                                         <listitem>
 337                                                 <para>An NTP server address. This option may be specified more than once.</para>
 338                                         </listitem>
 339                                 </varlistentry>
 340                                 <varlistentry>
 341                                         <term><varname>Bridge=</varname></term>
 342                                         <listitem>
 343                                                 <para>The name of the bridge to add the link to.</para>
 344                                         </listitem>
 345                                 </varlistentry>
 346                                 <varlistentry>
 347                                         <term><varname>Bond=</varname></term>
 348                                         <listitem>
 349                                                 <para>The name of the bond to add the link to.</para>
 350                                         </listitem>
 351                                 </varlistentry>
 352                                 <varlistentry>
 353                                         <term><varname>VLAN=</varname></term>
 354                                         <listitem>
 355                                                 <para>The name of a VLAN to create on the link. This option
 356                                                 may be specified more than once.</para>
 357                                         </listitem>
 358                                 </varlistentry>
 359                                 <varlistentry>
 360                                         <term><varname>MACVLAN=</varname></term>
 361                                         <listitem>
 362                                                 <para>The name of a MACVLAN to create on the link. This option
 363                                                 may be specified more than once.</para>
 364                                         </listitem>
 365                                 </varlistentry>
 366                                 <varlistentry>
 367                                         <term><varname>VXLAN=</varname></term>
 368                                         <listitem>
 369                                                 <para>The name of a VXLAN to create on the link. This option
 370                                                 may be specified more than once.</para>
 371                                         </listitem>
 372                                 </varlistentry>
 373                                 <varlistentry>
 374                                         <term><varname>Tunnel=</varname></term>
 375                                         <listitem>
 376                                                 <para>The name of a Tunnel to create on the link. This option
 377                                                 may be specified more than once.</para>
 378                                         </listitem>
 379                                 </varlistentry>
 380                         </variablelist>
 381
 382         </refsect1>
 383
 384         <refsect1>
 385                 <title>[Address] Section Options</title>
 386
 387                         <para>An <literal>[Address]</literal> section accepts the following keys.
 388                         Specify several <literal>[Address]</literal> sections to configure several
 389                         addresses.</para>
 390
 391                         <variablelist class='network-directives'>
 392                                 <varlistentry>
 393                                         <term><varname>Address=</varname></term>
 394                                         <listitem>
 395                                                 <para>As in the <literal>[Network]</literal> section. This key is mandatory.</para>
 396                                         </listitem>
 397                                 </varlistentry>
 398                                 <varlistentry>
 399                                         <term><varname>Peer=</varname></term>
 400                                         <listitem>
 401                                                 <para>The peer address in a point-to-point connection. Accepts the same format as
 402                                                 the <literal>Address</literal> key.</para>
 403                                         </listitem>
 404                                 </varlistentry>
 405                                 <varlistentry>
 406                                         <term><varname>Broadcast=</varname></term>
 407                                         <listitem>
 408                                                 <para>The broadcast address, which must be in the format described in
 409                                                 <citerefentry><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
 410                                                 This key only applies to IPv4 addresses. If it is not given, it is
 411                                                 derived from the <literal>Address</literal> key.</para>
 412                                         </listitem>
 413                                 </varlistentry>
 414                                 <varlistentry>
 415                                         <term><varname>Label=</varname></term>
 416                                         <listitem>
 417                                                 <para>An address label.</para>
 418                                         </listitem>
 419                                 </varlistentry>
 420                         </variablelist>
 421         </refsect1>
 422
 423         <refsect1>
 424                 <title>[Route] Section Options</title>
 425                         <para>The <literal>[Route]</literal> section accepts the following keys. Specify
 426                         several <literal>[Route]</literal> sections to configure several routes.</para>
 427
 428                         <variablelist class='network-directives'>
 429                                 <varlistentry>
 430                                         <term><varname>Gateway=</varname></term>
 431                                         <listitem>
 432                                                 <para>As in the <literal>[Network]</literal> section.</para>
 433                                         </listitem>
 434                                 </varlistentry>
 435                                 <varlistentry>
 436                                         <term><varname>Destination=</varname></term>
 437                                         <listitem>
 438                                                 <para>The destination prefix of the route. Possibly followed by a slash and the
 439                                                 prefixlength. If omitted, a full-length host route is assumed.</para>
 440                                         </listitem>
 441                                 </varlistentry>
 442                                 <varlistentry>
 443                                         <term><varname>Source=</varname></term>
 444                                         <listitem>
 445                                                 <para>The source prefix of the route. Possibly followed by a slash and the
 446                                                 prefixlength. If omitted, a full-length host route is assumed.</para>
 447                                         </listitem>
 448                                 </varlistentry>
 449                                 <varlistentry>
 450                                         <term><varname>Metric=</varname></term>
 451                                         <listitem>
 452                                                 <para>The metric of the route. An unsigned integer</para>
 453                                         </listitem>
 454                                 </varlistentry>
 455                         </variablelist>
 456         </refsect1>
 457
 458         <refsect1>
 459                 <title>[DHCP] Section Options</title>
 460                         <para>The <literal>[DHCP]</literal> section accepts the following keys:</para>
 461
 462                         <variablelist class='network-directives'>
 463                                 <varlistentry>
 464                                         <term><varname>UseDNS=</varname></term>
 465                                         <listitem>
 466                                                 <para>When true (the default), the DNS servers received from the DHCP server will
 467                                                 be used and take precedence over any statically configured ones.</para>
 468                                         </listitem>
 469                                 </varlistentry>
 470                                 <varlistentry>
 471                                         <term><varname>UseMTU=</varname></term>
 472                                         <listitem>
 473                                                 <para>When true, the interface maximum transmission unit from the DHCP server will
 474                                                 be used on the current link. Defaults to false.</para>
 475                                         </listitem>
 476                                 </varlistentry>
 477                                 <varlistentry>
 478                                         <term><varname>SendHostname=</varname></term>
 479                                         <listitem>
 480                                                 <para>When true (the default), the machine's hostname will be sent to the DHCP
 481                                                 server</para>
 482                                         </listitem>
 483                                 </varlistentry>
 484                                 <varlistentry>
 485                                         <term><varname>UseHostname=</varname></term>
 486                                         <listitem>
 487                                                 <para>When true (the default), the hostname received from the DHCP server
 488                                                 will be used as the transient hostname.</para>
 489                                         </listitem>
 490                                 </varlistentry>
 491                                 <varlistentry>
 492                                         <term><varname>UseDomains=</varname></term>
 493                                         <listitem>
 494                                                 <para>When true (not the default), the domain name received from the DHCP server
 495                                                 will be used for DNS resolution over this link.</para>
 496                                         </listitem>
 497                                 </varlistentry>
 498                                 <varlistentry>
 499                                         <term><varname>UseRoutes=</varname></term>
 500                                         <listitem>
 501                                                 <para>When true (the default), the static routes will be requested from the DHCP server
 502                                                 and added to the routing table with metric of 1024.</para>
 503                                         </listitem>
 504                                 </varlistentry>
 505                                 <varlistentry>
 506                                         <term><varname>CriticalConnection=</varname></term>
 507                                         <listitem>
 508                                                 <para>When true, the connection will never be torn down even if the DHCP lease
 509                                                 expires. This is contrary to the DHCP specification, but may be the best choice
 510                                                 if, say, the root filesystem relies on this connection. Defaults to false.</para>
 511                                         </listitem>
 512                                 </varlistentry>
 513                                 <varlistentry>
 514                                         <term><varname>VendorClassIdentifier=</varname></term>
 515                                         <listitem>
 516                                                 <para>The vendor class identifier used to identify vendor type and configuration.</para>
 517                                         </listitem>
 518                                 </varlistentry>
 519                                 <varlistentry>
 520                                         <term><varname>RequestBroadcast=</varname></term>
 521                                         <listitem>
 522                                                 <para>Request the server to use broadcast messages before the IP address has been
 523                                                 configured. This is necessary for devices that cannot receive RAW packets, or that
 524                                                 cannot receive packets at all before an IP address has been configured. On the other
 525                                                 hand, this must not be enabled on networks where broadcasts are filtered out.</para>
 526                                         </listitem>
 527                                 </varlistentry>
 528                                 <varlistentry>
 529                                         <term><varname>RouteMetric=</varname></term>
 530                                         <listitem>
 531                                                 <para>Set the routing metric for routes specified by the DHCP server.</para>
 532                                         </listitem>
 533                                 </varlistentry>
 534                        </variablelist>
 535
 536         </refsect1>
 537
 538         <refsect1>
 539                 <title>[BridgePort] Section Options</title>
 540                         <para>The <literal>[BridgePort]</literal> section accepts the following keys.</para>
 541                         <variablelist class='network-directives'>
 542                                 <varlistentry>
 543                                         <term><varname>Cost=</varname></term>
 544                                         <listitem>
 545                                           <para>Each port in a bridge may have different speed. Cost is used to decide which link to use. Faster interfaces should have lower costs</para>
 546                                         </listitem>
 547                                 </varlistentry>
 548                         </variablelist>
 549         </refsect1>
 550
 551         <refsect1>
 552                 <title>Example</title>
 553                 <example>
 554                         <title>/etc/systemd/network/50-static.network</title>
 555
 556                         <programlisting>[Match]
 557 Name=enp2s0
 558
 559 [Network]
 560 Address=192.168.0.15/24
 561 Gateway=192.168.0.1</programlisting>
 562                 </example>
 563
 564                 <example>
 565                         <title>/etc/systemd/network/80-dhcp.network</title>
 566
 567                         <programlisting>[Match]
 568 Name=en*
 569
 570 [Network]
 571 DHCP=both</programlisting>
 572                 </example>
 573
 574                 <example>
 575                         <title>/etc/systemd/network/bridge-static.network</title>
 576
 577                         <programlisting>[Match]
 578 Name=bridge0
 579
 580 [Network]
 581 Address=192.168.0.15/24
 582 Gateway=192.168.0.1
 583 DNS=192.168.0.1</programlisting>
 584                 </example>
 585
 586                 <example>
 587                         <title>/etc/systemd/network/bridge-slave-interface.network</title>
 588
 589                         <programlisting>[Match]
 590 Name=enp2s0
 591
 592 [Network]
 593 Bridge=bridge0</programlisting>
 594                 </example>
 595                 <example>
 596                         <title>/etc/systemd/network/ipip.network</title>
 597
 598                         <programlisting>[Match]
 599 Name=em1
 600
 601 [Network]
 602 Tunnel=ipip-tun</programlisting>
 603                 </example>
 604
 605                 <example>
 606                         <title>/etc/systemd/network/sit.network</title>
 607
 608                         <programlisting>[Match]
 609 Name=em1
 610
 611 [Network]
 612 Tunnel=sit-tun</programlisting>
 613                 </example>
 614
 615                 <example>
 616                         <title>/etc/systemd/network/gre.network</title>
 617
 618                         <programlisting>[Match]
 619 Name=em1
 620
 621 [Network]
 622 Tunnel=gre-tun</programlisting>
 623                 </example>
 624
 625                 <example>
 626                         <title>/etc/systemd/network/vti.network</title>
 627
 628                         <programlisting>[Match]
 629 Name=em1
 630
 631 [Network]
 632 Tunnel=vti-tun</programlisting>
 633                 </example>
 634         </refsect1>
 635
 636         <refsect1>
 637                 <title>See Also</title>
 638                 <para>
 639                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 640                         <citerefentry><refentrytitle>systemd-networkd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 641                         <citerefentry><refentrytitle>systemd.netdev</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 642                 </para>
 643         </refsect1>
 644
 645 </refentry>