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