man/systemd.network.xml

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  26
  27 <refentry id="systemd.network" conditional='ENABLE_NETWORKD'>
  28
  29   <refentryinfo>
  30     <title>systemd.network</title>
  31     <productname>systemd</productname>
  32
  33     <authorgroup>
  34       <author>
  35         <contrib>Developer</contrib>
  36         <firstname>Tom</firstname>
  37         <surname>Gundersen</surname>
  38         <email>teg@jklm.no</email>
  39       </author>
  40     </authorgroup>
  41   </refentryinfo>
  42
  43   <refmeta>
  44     <refentrytitle>systemd.network</refentrytitle>
  45     <manvolnum>5</manvolnum>
  46   </refmeta>
  47
  48   <refnamediv>
  49     <refname>systemd.network</refname>
  50     <refpurpose>Network configuration</refpurpose>
  51   </refnamediv>
  52
  53   <refsynopsisdiv>
  54     <para><filename><replaceable>network</replaceable>.network</filename></para>
  55   </refsynopsisdiv>
  56
  57   <refsect1>
  58     <title>Description</title>
  59
  60     <para>Network setup is performed by
  61     <citerefentry><refentrytitle>systemd-networkd</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
  62     </para>
  63
  64     <para>Network files must have the extension
  65     <filename>.network</filename>; other extensions are ignored.
  66     Networks are applied to links whenever the links appear.</para>
  67
  68     <para>The <filename>.network</filename> files are read from the
  69     files located in the system network directory
  70     <filename>&rootlibexecdir;/network</filename>, the volatile
  71     runtime network directory
  72     <filename>/run/systemd/network</filename> and the local
  73     administration network directory
  74     <filename>&pkgsysconfdir;/network</filename>. All configuration files
  75     are collectively sorted and processed in lexical order, regardless
  76     of the directories in which they live. However, files with
  77     identical filenames replace each other. Files in
  78     <filename>/etc</filename> have the highest priority, files in
  79     <filename>/run</filename> take precedence over files with the same
  80     name in <filename>/usr/lib</filename>. This can be used to
  81     override a system-supplied configuration file with a local file if
  82     needed; a symlink in <filename>/etc</filename> with the same name
  83     as a configuration file in <filename>/usr/lib</filename>, pointing
  84     to <filename>/dev/null</filename>, disables the configuration file
  85     entirely.</para>
  86
  87   </refsect1>
  88
  89   <refsect1>
  90     <title>[Match] Section Options</title>
  91
  92       <para>The network file contains a <literal>[Match]</literal>
  93       section, which determines if a given network file may be applied
  94       to a given device; and a <literal>[Network]</literal> section
  95       specifying how the device should be configured. The first (in
  96       lexical order) of the network files that matches a given device
  97       is applied, all later files are ignored, even if they match as
  98       well.</para>
  99
 100       <para>A network file is said to match a device if each of the
 101       entries in the <literal>[Match]</literal> section matches, or if
 102       the section is empty. The following keys are accepted:</para>
 103
 104       <variablelist class='network-directives'>
 105         <varlistentry>
 106           <term><varname>MACAddress=</varname></term>
 107           <listitem>
 108             <para>The hardware address.</para>
 109           </listitem>
 110         </varlistentry>
 111         <varlistentry>
 112           <term><varname>Path=</varname></term>
 113           <listitem>
 114             <para>A whitespace-separated list of shell-style globs
 115             matching the persistent path, as exposed by the udev
 116             property <literal>ID_PATH</literal>.</para>
 117           </listitem>
 118         </varlistentry>
 119         <varlistentry>
 120           <term><varname>Driver=</varname></term>
 121           <listitem>
 122             <para>A whitespace-separated list of shell-style globs
 123             matching the driver currently bound to the device, as
 124             exposed by the udev property <literal>DRIVER</literal>
 125             of its parent device, or if that is not set the driver
 126             as exposed by <literal>ethtool -i</literal> of the
 127             device itself.</para>
 128           </listitem>
 129         </varlistentry>
 130         <varlistentry>
 131           <term><varname>Type=</varname></term>
 132           <listitem>
 133             <para>A whitespace-separated list of shell-style globs
 134             matching the device type, as exposed by the udev property
 135             <literal>DEVTYPE</literal>.</para>
 136           </listitem>
 137         </varlistentry>
 138         <varlistentry>
 139           <term><varname>Name=</varname></term>
 140           <listitem>
 141             <para>A whitespace-separated list of shell-style globs
 142             matching the device name, as exposed by the udev property
 143             <literal>INTERFACE</literal>.</para>
 144           </listitem>
 145         </varlistentry>
 146         <varlistentry>
 147           <term><varname>Host=</varname></term>
 148           <listitem>
 149             <para>Matches against the hostname or machine ID of the
 150             host. See <literal>ConditionHost=</literal> in
 151             <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 152             for details.
 153             </para>
 154           </listitem>
 155         </varlistentry>
 156         <varlistentry>
 157           <term><varname>Virtualization=</varname></term>
 158           <listitem>
 159             <para>Checks whether the system is executed in a virtualized
 160             environment and optionally test whether it is a specific
 161             implementation. See <literal>ConditionVirtualization=</literal> in
 162             <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 163             for details.
 164             </para>
 165           </listitem>
 166         </varlistentry>
 167         <varlistentry>
 168           <term><varname>KernelCommandLine=</varname></term>
 169           <listitem>
 170             <para>Checks whether a specific kernel command line option is
 171             set (or if prefixed with the exclamation mark unset). See
 172             <literal>ConditionKernelCommandLine=</literal> in
 173             <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 174             for details.
 175             </para>
 176           </listitem>
 177         </varlistentry>
 178         <varlistentry>
 179           <term><varname>Architecture=</varname></term>
 180           <listitem>
 181             <para>Checks whether the system is running on a specific
 182             architecture. See <literal>ConditionArchitecture=</literal> in
 183             <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 184             for details.
 185             </para>
 186           </listitem>
 187         </varlistentry>
 188       </variablelist>
 189
 190   </refsect1>
 191
 192   <refsect1>
 193     <title>[Link] Section Options</title>
 194
 195     <para> The <literal>[Link]</literal> section accepts the following keys:</para>
 196
 197     <variablelist class='network-directives'>
 198       <varlistentry>
 199         <term><varname>MACAddress=</varname></term>
 200         <listitem>
 201           <para>The hardware address.</para>
 202         </listitem>
 203       </varlistentry>
 204       <varlistentry>
 205         <term><varname>MTUBytes=</varname></term>
 206         <listitem>
 207           <para>The maximum transmission unit in bytes to set for the
 208           device. The usual suffixes K, M, G, are supported and are
 209           understood to the base of 1024.</para>
 210         </listitem>
 211       </varlistentry>
 212     </variablelist>
 213   </refsect1>
 214
 215   <refsect1>
 216     <title>[Network] Section Options</title>
 217
 218       <para>The <literal>[Network]</literal> section accepts the following keys:</para>
 219
 220       <variablelist class='network-directives'>
 221         <varlistentry>
 222           <term><varname>Description=</varname></term>
 223           <listitem>
 224             <para>A description of the device. This is only used for
 225             presentation purposes.</para>
 226           </listitem>
 227         </varlistentry>
 228         <varlistentry>
 229           <term><varname>DHCP=</varname></term>
 230           <listitem>
 231             <para>Enables DHCPv4 and/or DHCPv6 support. Accepts
 232             <literal>yes</literal>, <literal>no</literal>,
 233             <literal>ipv4</literal>, or <literal>ipv6</literal>.</para>
 234
 235             <para>Please note that by default the domain name
 236             specified through DHCP is not used for name resolution.
 237             See option <option>UseDomains=</option> below.</para>
 238           </listitem>
 239         </varlistentry>
 240         <varlistentry>
 241           <term><varname>DHCPServer=</varname></term>
 242           <listitem>
 243             <para>A boolean. Enables a basic DHCPv4 server on the
 244             device. Mostly useful for handing out leases to container
 245             instances.</para>
 246           </listitem>
 247         </varlistentry>
 248         <varlistentry>
 249           <term><varname>LinkLocalAddressing=</varname></term>
 250           <listitem>
 251             <para>Enables link-local address autoconfiguration. Accepts
 252             <literal>yes</literal>, <literal>no</literal>,
 253             <literal>ipv4</literal>, or <literal>ipv6</literal>. Defaults to
 254             <literal>ipv6</literal>.</para>
 255           </listitem>
 256         </varlistentry>
 257         <varlistentry>
 258           <term><varname>IPv4LLRoute=</varname></term>
 259           <listitem>
 260             <para>A boolean. When true, sets up the route needed for
 261             non-IPv4LL hosts to communicate with IPv4LL-only hosts. Defaults
 262             to false.
 263             </para>
 264           </listitem>
 265         </varlistentry>
 266         <varlistentry>
 267           <term><varname>IPv6Token=</varname></term>
 268           <listitem>
 269             <para>An IPv6 address with the top 64 bits unset. When set, indicates the
 270             64 bits interface part of SLAAC IPv6 addresses for this link. By default
 271             it is autogenerated.</para>
 272           </listitem>
 273         </varlistentry>
 274         <varlistentry>
 275           <term><varname>LLMNR=</varname></term>
 276           <listitem>
 277             <para>A boolean or <literal>resolve</literal>. When true, enables
 278             Link-Local Multicast Name Resolution on the link, when set to
 279             <literal>resolve</literal> only resolution is enabled, but not
 280             announcement. Defaults to true.</para>
 281           </listitem>
 282         </varlistentry>
 283         <varlistentry>
 284           <term><varname>LLDP=</varname></term>
 285           <listitem>
 286             <para>A boolean. When true, enables LLDP link receive support.
 287             </para>
 288           </listitem>
 289         </varlistentry>
 290         <varlistentry>
 291           <term><varname>BindCarrier=</varname></term>
 292           <listitem>
 293             <para>A port or a list of ports. When set, controls the
 294             behaviour of the current interface. When all ports in the list
 295             are in an operational down state, the current interface is brought
 296             down. When at least one port has carrier, the current interface
 297             is brought up.
 298             </para>
 299           </listitem>
 300         </varlistentry>
 301         <varlistentry>
 302           <term><varname>Address=</varname></term>
 303           <listitem>
 304             <para>A static IPv4 or IPv6 address and its prefix length,
 305             separated by a <literal>/</literal> character. Specify
 306             this key more than once to configure several addresses.
 307             The format of the address must be as described in
 308             <citerefentry project='man-pages'><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
 309             This is a short-hand for an [Address] section only
 310             containing an Address key (see below). This option may be
 311             specified more than once.
 312             </para>
 313
 314             <para>If the specified address is 0.0.0.0 (for IPv4) or
 315             [::] (for IPv6), a new address range of the requested size
 316             is automatically allocated from a system-wide pool of
 317             unused ranges. The allocated range is checked against all
 318             current network interfaces and all known network
 319             configuration files to avoid address range conflicts. The
 320             default system-wide pool consists of 192.168.0.0/16,
 321             172.16.0.0/12 and 10.0.0.0/8 for IPv4, and fc00::/7 for
 322             IPv6. This functionality is useful to manage a large
 323             number of dynamically created network interfaces with the
 324             same network configuration and automatic address range
 325             assignment.</para>
 326
 327           </listitem>
 328         </varlistentry>
 329         <varlistentry>
 330           <term><varname>Gateway=</varname></term>
 331           <listitem>
 332             <para>The gateway address, which must be in the format
 333             described in
 334             <citerefentry project='man-pages'><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
 335             This is a short-hand for a [Route] section only containing
 336             a Gateway key. This option may be specified more than
 337             once.</para>
 338           </listitem>
 339         </varlistentry>
 340         <varlistentry>
 341           <term><varname>DNS=</varname></term>
 342           <listitem>
 343             <para>A DNS server address, which must be in the format
 344             described in
 345             <citerefentry project='man-pages'><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
 346             This option may be specified more than once.</para>
 347           </listitem>
 348         </varlistentry>
 349         <varlistentry>
 350           <term><varname>Domains=</varname></term>
 351           <listitem>
 352             <para>The domains used for DNS resolution over this link.</para>
 353           </listitem>
 354         </varlistentry>
 355         <varlistentry>
 356           <term><varname>NTP=</varname></term>
 357           <listitem>
 358             <para>An NTP server address. This option may be specified more than once.</para>
 359           </listitem>
 360         </varlistentry>
 361         <varlistentry>
 362           <term><varname>IPForward=</varname></term>
 363           <listitem><para>Configures IP forwarding for the network
 364           interface. If enabled incoming packets on the network
 365           interface will be forwarded to other interfaces according to
 366           the routing table. Takes either a boolean argument, or the
 367           values <literal>ipv4</literal> or <literal>ipv6</literal>,
 368           which only enables IP forwarding for the specified address
 369           family. This controls the
 370           <filename>net.ipv4.conf.&lt;interface&gt;.forwarding</filename>
 371           and
 372           <filename>net.ipv6.conf.&lt;interface&gt;.forwarding</filename>
 373           sysctl options of the network interface (see <ulink
 374           url="https://www.kernel.org/doc/Documentation/networking/ip-sysctl.txt">ip-sysctl.txt</ulink>
 375           for details about sysctl options). Defaults to
 376           <literal>no</literal>.</para>
 377
 378           <para>Note: unless this option is turned on, no IP
 379           forwarding is done on this interface, even if this is
 380           globally turned on in the kernel, with the
 381           <filename>net.ipv4.ip_forward</filename> and
 382           <filename>net.ipv4.ip_forward</filename> sysctl
 383           options.</para>
 384           </listitem>
 385         </varlistentry>
 386         <varlistentry>
 387           <term><varname>IPMasquerade=</varname></term>
 388           <listitem><para>Configures IP masquerading for the network
 389           interface. If enabled packets forwarded from the network
 390           interface will be appear as coming from the local host.
 391           Takes a boolean argument. Implies
 392           <varname>IPForward=ipv4</varname>. Defaults to
 393           <literal>no</literal>.</para></listitem>
 394         </varlistentry>
 395         <varlistentry>
 396           <term><varname>Bridge=</varname></term>
 397           <listitem>
 398             <para>The name of the bridge to add the link to.</para>
 399           </listitem>
 400         </varlistentry>
 401         <varlistentry>
 402           <term><varname>Bond=</varname></term>
 403           <listitem>
 404             <para>The name of the bond to add the link to.</para>
 405           </listitem>
 406         </varlistentry>
 407         <varlistentry>
 408           <term><varname>VLAN=</varname></term>
 409           <listitem>
 410             <para>The name of a VLAN to create on the link. This
 411             option may be specified more than once.</para>
 412           </listitem>
 413         </varlistentry>
 414         <varlistentry>
 415           <term><varname>MACVLAN=</varname></term>
 416           <listitem>
 417             <para>The name of a MACVLAN to create on the link. This
 418             option may be specified more than once.</para>
 419           </listitem>
 420         </varlistentry>
 421         <varlistentry>
 422           <term><varname>VXLAN=</varname></term>
 423           <listitem>
 424             <para>The name of a VXLAN to create on the link. This
 425             option may be specified more than once.</para>
 426           </listitem>
 427         </varlistentry>
 428         <varlistentry>
 429           <term><varname>Tunnel=</varname></term>
 430           <listitem>
 431             <para>The name of a Tunnel to create on the link. This
 432             option may be specified more than once.</para>
 433           </listitem>
 434         </varlistentry>
 435       </variablelist>
 436
 437   </refsect1>
 438
 439   <refsect1>
 440     <title>[Address] Section Options</title>
 441
 442       <para>An <literal>[Address]</literal> section accepts the
 443       following keys. Specify several <literal>[Address]</literal>
 444       sections to configure several addresses.</para>
 445
 446       <variablelist class='network-directives'>
 447         <varlistentry>
 448           <term><varname>Address=</varname></term>
 449           <listitem>
 450             <para>As in the <literal>[Network]</literal> section. This
 451             key is mandatory.</para>
 452           </listitem>
 453         </varlistentry>
 454         <varlistentry>
 455           <term><varname>Peer=</varname></term>
 456           <listitem>
 457             <para>The peer address in a point-to-point connection.
 458             Accepts the same format as the <literal>Address</literal>
 459             key.</para>
 460           </listitem>
 461         </varlistentry>
 462         <varlistentry>
 463           <term><varname>Broadcast=</varname></term>
 464           <listitem>
 465             <para>The broadcast address, which must be in the format
 466             described in
 467             <citerefentry project='man-pages'><refentrytitle>inet_pton</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
 468             This key only applies to IPv4 addresses. If it is not
 469             given, it is derived from the <literal>Address</literal>
 470             key.</para>
 471           </listitem>
 472         </varlistentry>
 473         <varlistentry>
 474           <term><varname>Label=</varname></term>
 475           <listitem>
 476             <para>An address label.</para>
 477           </listitem>
 478         </varlistentry>
 479       </variablelist>
 480   </refsect1>
 481
 482   <refsect1>
 483     <title>[Route] Section Options</title>
 484       <para>The <literal>[Route]</literal> section accepts the
 485       following keys. Specify several <literal>[Route]</literal>
 486       sections to configure several routes.</para>
 487
 488       <variablelist class='network-directives'>
 489         <varlistentry>
 490           <term><varname>Gateway=</varname></term>
 491           <listitem>
 492             <para>As in the <literal>[Network]</literal> section.</para>
 493           </listitem>
 494         </varlistentry>
 495         <varlistentry>
 496           <term><varname>Destination=</varname></term>
 497           <listitem>
 498             <para>The destination prefix of the route. Possibly
 499             followed by a slash and the prefixlength. If omitted, a
 500             full-length host route is assumed.</para>
 501           </listitem>
 502         </varlistentry>
 503         <varlistentry>
 504           <term><varname>Source=</varname></term>
 505           <listitem>
 506             <para>The source prefix of the route. Possibly followed by
 507             a slash and the prefixlength. If omitted, a full-length
 508             host route is assumed.</para>
 509           </listitem>
 510         </varlistentry>
 511         <varlistentry>
 512           <term><varname>Metric=</varname></term>
 513           <listitem>
 514             <para>The metric of the route. An unsigned integer</para>
 515           </listitem>
 516         </varlistentry>
 517         <varlistentry>
 518           <term><varname>Scope=</varname></term>
 519           <listitem>
 520             <para>The scope of the route. One of the values <literal>global</literal>,
 521             <literal>link</literal> or <literal>host</literal>. Defaults to
 522             <literal>global</literal>.</para>
 523           </listitem>
 524         </varlistentry>
 525       </variablelist>
 526   </refsect1>
 527
 528   <refsect1>
 529     <title>[DHCP] Section Options</title>
 530       <para>The <literal>[DHCP]</literal> section accepts the following keys:</para>
 531
 532       <variablelist class='network-directives'>
 533         <varlistentry>
 534           <term><varname>UseDNS=</varname></term>
 535           <listitem>
 536             <para>When true (the default), the DNS servers received
 537             from the DHCP server will be used and take precedence over
 538             any statically configured ones.</para>
 539
 540             <para>This corresponds to the <option>nameserver</option>
 541             option in <citerefentry project='man-pages'><refentrytitle>resolv.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
 542           </listitem>
 543         </varlistentry>
 544         <varlistentry>
 545           <term><varname>UseNTP=</varname></term>
 546           <listitem>
 547             <para>When true (the default), the NTP servers received
 548             from the DHCP server will be used by systemd-timesyncd
 549             and take precedence over any statically configured ones.</para>
 550           </listitem>
 551         </varlistentry>
 552         <varlistentry>
 553           <term><varname>UseMTU=</varname></term>
 554           <listitem>
 555             <para>When true, the interface maximum transmission unit
 556             from the DHCP server will be used on the current link.
 557             Defaults to false.</para>
 558           </listitem>
 559         </varlistentry>
 560         <varlistentry>
 561           <term><varname>SendHostname=</varname></term>
 562           <listitem>
 563             <para>When true (the default), the machine's hostname will be sent to the DHCP
 564             server</para>
 565           </listitem>
 566         </varlistentry>
 567         <varlistentry>
 568           <term><varname>UseHostname=</varname></term>
 569           <listitem>
 570             <para>When true (the default), the hostname received from
 571             the DHCP server will be used as the transient
 572             hostname.</para>
 573           </listitem>
 574         </varlistentry>
 575         <varlistentry>
 576           <term><varname>UseDomains=</varname></term>
 577           <listitem>
 578             <para>When true (not the default), the domain name
 579             received from the DHCP server will be used for DNS
 580             resolution over this link. When a name cannot be resolved
 581             as specified, the domain name will be used a suffix and
 582             name resolution of that will be attempted.</para>
 583
 584             <para>This corresponds to the <option>domain</option>
 585             option in <citerefentry project='man-pages'><refentrytitle>resolv.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 586             and should not be enabled on untrusted networks.</para>
 587           </listitem>
 588         </varlistentry>
 589         <varlistentry>
 590           <term><varname>UseRoutes=</varname></term>
 591           <listitem>
 592             <para>When true (the default), the static routes will be
 593             requested from the DHCP server and added to the routing
 594             table with metric of 1024.</para>
 595           </listitem>
 596         </varlistentry>
 597         <varlistentry>
 598           <term><varname>CriticalConnection=</varname></term>
 599           <listitem>
 600             <para>When true, the connection will never be torn down
 601             even if the DHCP lease expires. This is contrary to the
 602             DHCP specification, but may be the best choice if, say,
 603             the root filesystem relies on this connection. Defaults to
 604             false.</para>
 605           </listitem>
 606         </varlistentry>
 607         <varlistentry>
 608           <term><varname>ClientIdentifier=</varname></term>
 609           <listitem>
 610             <para>DHCP client identifier to use. Either <literal>mac</literal>
 611             to use the MAC address of the link or <literal>duid</literal>
 612             (the default) to use a RFC4361-compliant Client ID.</para>
 613           </listitem>
 614         </varlistentry>
 615         <varlistentry>
 616           <term><varname>VendorClassIdentifier=</varname></term>
 617           <listitem>
 618             <para>The vendor class identifier used to identify vendor
 619             type and configuration.</para>
 620           </listitem>
 621         </varlistentry>
 622         <varlistentry>
 623           <term><varname>RequestBroadcast=</varname></term>
 624           <listitem>
 625             <para>Request the server to use broadcast messages before
 626             the IP address has been configured. This is necessary for
 627             devices that cannot receive RAW packets, or that cannot
 628             receive packets at all before an IP address has been
 629             configured. On the other hand, this must not be enabled on
 630             networks where broadcasts are filtered out.</para>
 631           </listitem>
 632         </varlistentry>
 633         <varlistentry>
 634           <term><varname>RouteMetric=</varname></term>
 635           <listitem>
 636             <para>Set the routing metric for routes specified by the
 637             DHCP server.</para>
 638           </listitem>
 639         </varlistentry>
 640            </variablelist>
 641
 642   </refsect1>
 643
 644   <refsect1>
 645     <title>[Bridge] Section Options</title>
 646       <para>The <literal>[Bridge]</literal> section accepts the
 647       following keys.</para>
 648       <variablelist class='network-directives'>
 649         <varlistentry>
 650           <term><varname>Cost=</varname></term>
 651           <listitem>
 652             <para>Each port in a bridge may have different speed. Cost
 653             is used to decide which link to use. Faster interfaces
 654             should have lower costs</para>
 655           </listitem>
 656         </varlistentry>
 657       </variablelist>
 658   </refsect1>
 659
 660   <refsect1>
 661     <title>[BridgeFDB] Section Options</title>
 662       <para>The <literal>[BridgeFDB]</literal> section manages the
 663       forwarding database table of a port and accepts the following
 664       keys. Specify several <literal>[BridgeFDB]</literal> sections to
 665       configure several static MAC table entries.</para>
 666
 667       <variablelist class='network-directives'>
 668         <varlistentry>
 669           <term><varname>MACAddress=</varname></term>
 670           <listitem>
 671             <para>As in the <literal>[Network]</literal> section. This
 672             key is mandatory.</para>
 673           </listitem>
 674         </varlistentry>
 675         <varlistentry>
 676           <term><varname>VLANId=</varname></term>
 677           <listitem>
 678             <para>The VLAN Id for the new static MAC table entry. If
 679             omitted, no VLAN Id info is appended to the new static MAC
 680             table entry.</para>
 681           </listitem>
 682         </varlistentry>
 683       </variablelist>
 684   </refsect1>
 685
 686   <refsect1>
 687     <title>Example</title>
 688     <example>
 689       <title>&pkgsysconfdir;/network/50-static.network</title>
 690
 691       <programlisting>[Match]
 692 Name=enp2s0
 693
 694 [Network]
 695 Address=192.168.0.15/24
 696 Gateway=192.168.0.1</programlisting>
 697     </example>
 698
 699     <example>
 700       <title>&pkgsysconfdir;/network/80-dhcp.network</title>
 701
 702       <programlisting>[Match]
 703 Name=en*
 704
 705 [Network]
 706 DHCP=yes</programlisting>
 707     </example>
 708
 709     <example>
 710       <title>&pkgsysconfdir;/network/bridge-static.network</title>
 711
 712       <programlisting>[Match]
 713 Name=bridge0
 714
 715 [Network]
 716 Address=192.168.0.15/24
 717 Gateway=192.168.0.1
 718 DNS=192.168.0.1</programlisting>
 719     </example>
 720
 721     <example>
 722       <title>&pkgsysconfdir;/network/bridge-slave-interface.network</title>
 723
 724       <programlisting>[Match]
 725 Name=enp2s0
 726
 727 [Network]
 728 Bridge=bridge0</programlisting>
 729     </example>
 730     <example>
 731       <title>&pkgsysconfdir;/network/ipip.network</title>
 732
 733       <programlisting>[Match]
 734 Name=em1
 735
 736 [Network]
 737 Tunnel=ipip-tun</programlisting>
 738     </example>
 739
 740     <example>
 741       <title>&pkgsysconfdir;/network/sit.network</title>
 742
 743       <programlisting>[Match]
 744 Name=em1
 745
 746 [Network]
 747 Tunnel=sit-tun</programlisting>
 748     </example>
 749
 750     <example>
 751       <title>&pkgsysconfdir;/network/gre.network</title>
 752
 753       <programlisting>[Match]
 754 Name=em1
 755
 756 [Network]
 757 Tunnel=gre-tun</programlisting>
 758     </example>
 759
 760     <example>
 761       <title>&pkgsysconfdir;/network/vti.network</title>
 762
 763       <programlisting>[Match]
 764 Name=em1
 765
 766 [Network]
 767 Tunnel=vti-tun</programlisting>
 768     </example>
 769   </refsect1>
 770
 771   <refsect1>
 772     <title>See Also</title>
 773     <para>
 774       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 775       <citerefentry><refentrytitle>systemd-networkd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 776       <citerefentry><refentrytitle>systemd.link</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 777       <citerefentry><refentrytitle>systemd.netdev</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 778     </para>
 779   </refsect1>
 780
 781 </refentry>