man/systemd.netdev.xml

   1 <?xml version='1.0'?> <!--*-nxml-*-->
   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
   3   "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd" [
   4 <!ENTITY % entities SYSTEM "custom-entities.ent" >
   5 %entities;
   6 ]>
   7
   8 <!--
   9   This file is part of systemd.
  10
  11   Copyright 2013 Tom Gundersen
  12
  13   systemd is free software; you can redistribute it and/or modify it
  14   under the terms of the GNU Lesser General Public License as published by
  15   the Free Software Foundation; either version 2.1 of the License, or
  16   (at your option) any later version.
  17
  18   systemd is distributed in the hope that it will be useful, but
  19   WITHOUT ANY WARRANTY; without even the implied warranty of
  20   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  21   Lesser General Public License for more details.
  22
  23   You should have received a copy of the GNU Lesser General Public License
  24   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  25 -->
  26
  27 <refentry id="systemd.netdev" 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.netdev</refentrytitle>
  45     <manvolnum>5</manvolnum>
  46   </refmeta>
  47
  48   <refnamediv>
  49     <refname>systemd.netdev</refname>
  50     <refpurpose>Virtual Network Device configuration</refpurpose>
  51   </refnamediv>
  52
  53   <refsynopsisdiv>
  54     <para><filename><replaceable>netdev</replaceable>.netdev</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>Virtual Network Device files must have the extension
  65     <filename>.netdev</filename>; other extensions are ignored.
  66     Virtual network devices are created as soon as networkd is
  67     started. If a netdev with the specified name already exists,
  68     networkd will use that as-is rather than create its own. Note that
  69     the settings of the pre-existing netdev will not be changed by
  70     networkd.</para>
  71
  72     <para>The <filename>.netdev</filename> files are read from the
  73     files located in the system network directory
  74     <filename>&rootlibexecdir;/network</filename>, the volatile
  75     runtime network directory
  76     <filename>/run/systemd/network</filename> and the local
  77     administration network directory
  78     <filename>&pkgsysconfdir;/network</filename>. All configuration files
  79     are collectively sorted and processed in lexical order, regardless
  80     of the directories in which they live. However, files with
  81     identical filenames replace each other. Files in
  82     <filename>/etc</filename> have the highest priority, files in
  83     <filename>/run</filename> take precedence over files with the same
  84     name in <filename>&rootprefix;/lib</filename>. This can be used to
  85     override a system-supplied configuration file with a local file if
  86     needed; a symlink in <filename>/etc</filename> with the same name
  87     as a configuration file in <filename>&rootprefix;/lib</filename>, pointing
  88     to <filename>/dev/null</filename>, disables the configuration file
  89     entirely.</para>
  90
  91   </refsect1>
  92
  93   <refsect1>
  94     <title>Supported netdev kinds</title>
  95
  96     <para>The following kinds of virtual network devices may be
  97     configured in <filename>.netdev</filename> files:</para>
  98
  99     <table>
 100       <title>Supported kinds of virtual network devices</title>
 101
 102       <tgroup cols='2'>
 103         <colspec colname='kind' />
 104         <colspec colname='explanation' />
 105         <thead><row>
 106           <entry>Kind</entry>
 107           <entry>Description</entry>
 108         </row></thead>
 109         <tbody>
 110           <row><entry><varname>bond</varname></entry>
 111           <entry>A bond device is an aggregation of all its slave devices. See <ulink url="https://www.kernel.org/doc/Documentation/networking/bonding.txt">Linux Ethernet Bonding Driver HOWTO</ulink> for details.Local configuration</entry></row>
 112
 113           <row><entry><varname>bridge</varname></entry>
 114           <entry>A bridge device is a software switch, each of its slave devices and the bridge itself are ports of the switch.</entry></row>
 115
 116           <row><entry><varname>dummy</varname></entry>
 117           <entry>A dummy device drops all packets sent to it.</entry></row>
 118
 119           <row><entry><varname>gre</varname></entry>
 120           <entry>A Level 3 GRE tunnel over IPv4. See <ulink url="https://tools.ietf.org/html/rfc2784">RFC 2784</ulink> for details.</entry></row>
 121
 122           <row><entry><varname>gretap</varname></entry>
 123           <entry>A Level 2 GRE tunnel over IPv4.</entry></row>
 124
 125           <row><entry><varname>ip6gre</varname></entry>
 126           <entry>A Level 3 GRE tunnel over IPv6.</entry></row>
 127
 128           <row><entry><varname>ip6tnl</varname></entry>
 129           <entry>An IPv4 or IPv6 tunnel over IPv6</entry></row>
 130
 131           <row><entry><varname>ip6gretap</varname></entry>
 132           <entry>An Level 2 GRE tunnel over IPv6.</entry></row>
 133
 134           <row><entry><varname>ipip</varname></entry>
 135           <entry>An IPv4 over IPv4 tunnel.</entry></row>
 136
 137           <row><entry><varname>ipvlan</varname></entry>
 138           <entry>An ipvlan device is a stacked device which receives packets from its underlying device based on IP address filtering.</entry></row>
 139
 140           <row><entry><varname>macvlan</varname></entry>
 141           <entry>A macvlan device is a stacked device which receives packets from its underlying device based on MAC address filtering.</entry></row>
 142
 143           <row><entry><varname>sit</varname></entry>
 144           <entry>An IPv6 over IPv4 tunnel.</entry></row>
 145
 146           <row><entry><varname>tap</varname></entry>
 147           <entry>A persistent Level 2 tunnel between a network device and a device node.</entry></row>
 148
 149           <row><entry><varname>tun</varname></entry>
 150           <entry>A persistent Level 3 tunnel between a network device and a device node.</entry></row>
 151
 152           <row><entry><varname>veth</varname></entry>
 153           <entry>An ethernet tunnel between a pair of network devices.</entry></row>
 154
 155           <row><entry><varname>vlan</varname></entry>
 156           <entry>A VLAN is a stacked device which receives packets from its underlying device based on VLAN tagging. See <ulink url="http://www.ieee802.org/1/pages/802.1Q.html">IEEE 802.1Q</ulink> for details.</entry></row>
 157
 158           <row><entry><varname>vti</varname></entry>
 159           <entry>An IPv4 over IPSec tunnel.</entry></row>
 160
 161           <row><entry><varname>vti6</varname></entry>
 162           <entry>An IPv6 over IPSec tunnel.</entry></row>
 163
 164           <row><entry><varname>vxlan</varname></entry>
 165           <entry>A virtual extensible LAN (vxlan), for connecting Cloud computing deployments.</entry></row>
 166         </tbody>
 167       </tgroup>
 168     </table>
 169
 170   </refsect1>
 171
 172   <refsect1>
 173     <title>[Match] Section Options</title>
 174
 175     <para>A virtual network device is only created if the
 176     <literal>[Match]</literal> section matches the current
 177     environment, or if the section is empty. The following keys are
 178     accepted:</para>
 179
 180     <variablelist class='network-directives'>
 181       <varlistentry>
 182         <term><varname>Host=</varname></term>
 183         <listitem>
 184           <para>Matches against the hostname or machine ID of the
 185           host. See <literal>ConditionHost=</literal> in
 186           <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 187           for details.
 188           </para>
 189         </listitem>
 190       </varlistentry>
 191       <varlistentry>
 192         <term><varname>Virtualization=</varname></term>
 193         <listitem>
 194           <para>Checks whether the system is executed in a virtualized
 195           environment and optionally test whether it is a specific
 196           implementation. See
 197           <literal>ConditionVirtualization=</literal> in
 198           <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 199           for details.
 200           </para>
 201         </listitem>
 202       </varlistentry>
 203       <varlistentry>
 204         <term><varname>KernelCommandLine=</varname></term>
 205         <listitem>
 206           <para>Checks whether a specific kernel command line option
 207           is set (or if prefixed with the exclamation mark unset). See
 208           <literal>ConditionKernelCommandLine=</literal> in
 209           <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 210           for details.
 211           </para>
 212         </listitem>
 213       </varlistentry>
 214       <varlistentry>
 215         <term><varname>Architecture=</varname></term>
 216         <listitem>
 217           <para>Checks whether the system is running on a specific
 218           architecture. See <literal>ConditionArchitecture=</literal> in
 219           <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 220           for details.
 221           </para>
 222         </listitem>
 223       </varlistentry>
 224     </variablelist>
 225
 226   </refsect1>
 227
 228   <refsect1>
 229     <title>[NetDev] Section Options</title>
 230
 231       <para>The <literal>[NetDev]</literal> section accepts the
 232       following keys:</para>
 233
 234       <variablelist class='network-directives'>
 235         <varlistentry>
 236           <term><varname>Description=</varname></term>
 237           <listitem>
 238             <para>A free-form description of the netdev.</para>
 239           </listitem>
 240         </varlistentry>
 241         <varlistentry>
 242           <term><varname>Name=</varname></term>
 243           <listitem>
 244             <para>The interface name used when creating the netdev.
 245             This option is compulsory.</para>
 246           </listitem>
 247         </varlistentry>
 248         <varlistentry>
 249           <term><varname>Kind=</varname></term>
 250           <listitem>
 251             <para>The netdev kind. This option is compulsory. See the
 252             <literal>Supported netdev kinds</literal> section for the
 253             valid keys.</para>
 254           </listitem>
 255         </varlistentry>
 256         <varlistentry>
 257           <term><varname>MTUBytes=</varname></term>
 258           <listitem>
 259             <para>The maximum transmission unit in bytes to set for
 260             the device. The usual suffixes K, M, G, are supported and
 261             are understood to the base of 1024. This key is not
 262             currently supported for <literal>tun</literal> or
 263             <literal>tap</literal> devices.
 264             </para>
 265           </listitem>
 266         </varlistentry>
 267         <varlistentry>
 268           <term><varname>MACAddress=</varname></term>
 269           <listitem>
 270             <para>The MAC address to use for the device. If none is
 271             given, one is generated based on the interface name and
 272             the
 273             <citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
 274             This key is not currently supported for
 275             <literal>tun</literal> or <literal>tap</literal> devices.
 276             </para>
 277           </listitem>
 278         </varlistentry>
 279       </variablelist>
 280   </refsect1>
 281
 282   <refsect1>
 283     <title>[VLAN] Section Options</title>
 284
 285       <para>The <literal>[VLAN]</literal> section only applies for
 286       netdevs of kind <literal>vlan</literal>, and accepts the
 287       following key:</para>
 288
 289       <variablelist class='network-directives'>
 290         <varlistentry>
 291           <term><varname>Id=</varname></term>
 292           <listitem>
 293             <para>The VLAN ID to use. An integer in the range 0–4094.
 294             This option is compulsory.</para>
 295           </listitem>
 296         </varlistentry>
 297       </variablelist>
 298
 299   </refsect1>
 300
 301   <refsect1>
 302     <title>[MACVLAN] Section Options</title>
 303
 304     <para>The <literal>[MACVLAN]</literal> section only applies for
 305     netdevs of kind <literal>macvlan</literal>, and accepts the
 306     following key:</para>
 307
 308     <variablelist class='network-directives'>
 309       <varlistentry>
 310         <term><varname>Mode=</varname></term>
 311         <listitem>
 312           <para>The MACVLAN mode to use. The supported options are
 313           <literal>private</literal>,
 314           <literal>vepa</literal>,
 315           <literal>bridge</literal>, and
 316           <literal>passthru</literal>.
 317           </para>
 318         </listitem>
 319       </varlistentry>
 320     </variablelist>
 321
 322   </refsect1>
 323
 324   <refsect1>
 325     <title>[IPVLAN] Section Options</title>
 326
 327     <para>The <literal>[IPVLAN]</literal> section only applies for
 328     netdevs of kind <literal>ipvlan</literal>, and accepts the
 329     following key:</para>
 330
 331     <variablelist class='network-directives'>
 332       <varlistentry>
 333         <term><varname>Mode=</varname></term>
 334           <listitem>
 335             <para>The IPVLAN mode to use. The supported options are
 336             <literal>L2</literal> and <literal>L3</literal>.
 337             </para>
 338           </listitem>
 339       </varlistentry>
 340     </variablelist>
 341
 342   </refsect1>
 343
 344   <refsect1>
 345     <title>[VXLAN] Section Options</title>
 346     <para>The <literal>[VXLAN]</literal> section only applies for
 347     netdevs of kind <literal>vxlan</literal>, and accepts the
 348     following keys:</para>
 349
 350     <variablelist class='network-directives'>
 351       <varlistentry>
 352         <term><varname>Id=</varname></term>
 353         <listitem>
 354           <para>The VXLAN ID to use.</para>
 355         </listitem>
 356       </varlistentry>
 357       <varlistentry>
 358         <term><varname>Group=</varname></term>
 359         <listitem>
 360           <para>An assigned multicast group IP address.</para>
 361         </listitem>
 362       </varlistentry>
 363       <varlistentry>
 364         <term><varname>TOS=</varname></term>
 365         <listitem>
 366           <para>The Type Of Service byte value for a vxlan interface.</para>
 367         </listitem>
 368       </varlistentry>
 369       <varlistentry>
 370         <term><varname>TTL=</varname></term>
 371         <listitem>
 372           <para>A fixed Time To Live N on Virtual eXtensible Local
 373           Area Network packets. N is a number in the range 1-255. 0
 374           is a special value meaning that packets inherit the TTL
 375           value.</para>
 376         </listitem>
 377       </varlistentry>
 378       <varlistentry>
 379         <term><varname>MacLearning=</varname></term>
 380         <listitem>
 381           <para>A boolean. When true, enables dynamic MAC learning
 382           to discover remote MAC addresses.</para>
 383         </listitem>
 384       </varlistentry>
 385       <varlistentry>
 386         <term><varname>FDBAgeingSec=</varname></term>
 387         <listitem>
 388           <para>The lifetime of Forwarding Database entry learnt by
 389           the kernel in seconds.</para>
 390         </listitem>
 391       </varlistentry>
 392       <varlistentry>
 393         <term><varname>ARPProxy=</varname></term>
 394         <listitem>
 395           <para>A boolean. When true, enables ARP proxy.</para>
 396         </listitem>
 397       </varlistentry>
 398       <varlistentry>
 399         <term><varname>L2MissNotification=</varname></term>
 400         <listitem>
 401           <para>A boolean. When true, enables netlink LLADDR miss
 402           notifications.</para>
 403         </listitem>
 404       </varlistentry>
 405       <varlistentry>
 406         <term><varname>L3MissNotification=</varname></term>
 407         <listitem>
 408           <para>A boolean. When true, enables netlink IP ADDR miss
 409           notifications.</para>
 410         </listitem>
 411       </varlistentry>
 412       <varlistentry>
 413         <term><varname>RouteShortCircuit=</varname></term>
 414         <listitem>
 415           <para>A boolean. When true route short circuit is turned
 416           on.</para>
 417         </listitem>
 418       </varlistentry>
 419       <varlistentry>
 420         <term><varname>UDPCheckSum=</varname></term>
 421         <listitem>
 422           <para>A boolean. When true transmitting UDP checksums when doing VXLAN/IPv4 is turned on.</para>
 423         </listitem>
 424       </varlistentry>
 425       <varlistentry>
 426         <term><varname>UDP6ZeroChecksumTx=</varname></term>
 427         <listitem>
 428           <para>A boolean. When true sending zero checksums in VXLAN/IPv6 is turned on.</para>
 429         </listitem>
 430       </varlistentry>
 431       <varlistentry>
 432         <term><varname>UDP6ZeroCheckSumRx=</varname></term>
 433         <listitem>
 434           <para>A boolean. When true receiving zero checksums in VXLAN/IPv6 is turned on.</para>
 435         </listitem>
 436       </varlistentry>
 437     </variablelist>
 438   </refsect1>
 439   <refsect1>
 440     <title>[Tunnel] Section Options</title>
 441
 442     <para>The <literal>[Tunnel]</literal> section only applies for
 443     netdevs of kind
 444     <literal>ipip</literal>,
 445     <literal>sit</literal>,
 446     <literal>gre</literal>,
 447     <literal>gretap</literal>,
 448     <literal>ip6gre</literal>,
 449     <literal>ip6gretap</literal>,
 450     <literal>vti</literal>,
 451     <literal>vti6</literal>, and
 452     <literal>ip6tnl</literal> and accepts
 453     the following keys:</para>
 454
 455     <variablelist class='network-directives'>
 456       <varlistentry>
 457         <term><varname>Local=</varname></term>
 458         <listitem>
 459           <para>A static local address for tunneled packets. It must
 460           be an address on another interface of this host.</para>
 461         </listitem>
 462       </varlistentry>
 463       <varlistentry>
 464         <term><varname>Remote=</varname></term>
 465         <listitem>
 466           <para>The remote endpoint of the tunnel.</para>
 467         </listitem>
 468       </varlistentry>
 469       <varlistentry>
 470         <term><varname>TOS=</varname></term>
 471         <listitem>
 472           <para>The Type Of Service byte value for a tunnel interface.
 473           For details about the TOS see the
 474           <ulink url="http://tools.ietf.org/html/rfc1349"> Type of
 475           Service in the Internet Protocol Suite </ulink> document.
 476           </para>
 477         </listitem>
 478       </varlistentry>
 479       <varlistentry>
 480         <term><varname>TTL=</varname></term>
 481         <listitem>
 482           <para>A fixed Time To Live N on tunneled packets. N is a
 483           number in the range 1-255. 0 is a special value meaning that
 484           packets inherit the TTL value. The default value for IPv4
 485           tunnels is: inherit. The default value for IPv6 tunnels is:
 486           64.</para>
 487         </listitem>
 488       </varlistentry>
 489       <varlistentry>
 490         <term><varname>DiscoverPathMTU=</varname></term>
 491         <listitem>
 492           <para>A boolean. When true, enables Path MTU Discovery on
 493           the tunnel.</para>
 494         </listitem>
 495       </varlistentry>
 496       <varlistentry>
 497         <term><varname>Mode=</varname></term>
 498         <listitem>
 499           <para>An <literal>ip6tnl</literal> tunnels can have three
 500           modes
 501           <literal>ip6ip6</literal> for IPv6 over IPv6,
 502           <literal>ipip6</literal> for IPv4 over IPv6 or
 503           <literal>any</literal> for either.
 504           </para>
 505         </listitem>
 506       </varlistentry>
 507     </variablelist>
 508   </refsect1>
 509   <refsect1>
 510     <title>[Peer] Section Options</title>
 511
 512       <para>The <literal>[Peer]</literal> section only applies for
 513       netdevs of kind <literal>veth</literal> and accepts the
 514       following key:</para>
 515
 516       <variablelist class='network-directives'>
 517         <varlistentry>
 518           <term><varname>Name=</varname></term>
 519           <listitem>
 520             <para>The interface name used when creating the netdev.
 521             This option is compulsory.</para>
 522           </listitem>
 523         </varlistentry>
 524         <varlistentry>
 525           <term><varname>MACAddress=</varname></term>
 526           <listitem>
 527             <para>The peer MACAddress, if not set it is generated in
 528             the same way as the MAC address of the main
 529             interface.</para>
 530           </listitem>
 531         </varlistentry>
 532       </variablelist>
 533   </refsect1>
 534   <refsect1>
 535     <title>[Tun] Section Options</title>
 536
 537     <para>The <literal>[Tun]</literal> section only applies for
 538     netdevs of kind <literal>tun</literal>, and accepts the following
 539     keys:</para>
 540
 541     <variablelist class='network-directives'>
 542       <varlistentry>
 543         <term><varname>OneQueue=</varname></term>
 544         <listitem><para>Takes a boolean argument. Configures whether
 545         all packets are queued at the device (enabled), or a fixed
 546         number of packets are queued at the device and the rest at the
 547         <literal>qdisc</literal>. Defaults to
 548         <literal>no</literal>.</para>
 549         </listitem>
 550       </varlistentry>
 551       <varlistentry>
 552         <term><varname>MultiQueue=</varname></term>
 553         <listitem><para>Takes a boolean argument. Configures whether
 554         to use multiple file descriptors (queues) to parallelize
 555         packets sending and receiving. Defaults to
 556         <literal>no</literal>.</para>
 557         </listitem>
 558       </varlistentry>
 559       <varlistentry>
 560         <term><varname>PacketInfo=</varname></term>
 561         <listitem><para>Takes a boolean argument. Configures whether
 562         packets should be prepended with four extra bytes (two flag
 563         bytes and two protocol bytes). If disabled it indicates that
 564         the packets will be pure IP packets. Defaults to
 565         <literal>no</literal>.</para>
 566         </listitem>
 567       </varlistentry>
 568       <varlistentry>
 569         <term><varname>User=</varname></term>
 570         <listitem><para>User to grant access to the
 571         <filename>/dev/net/tun</filename> device.</para>
 572         </listitem>
 573       </varlistentry>
 574       <varlistentry>
 575         <term><varname>Group=</varname></term>
 576         <listitem><para>Group to grant access to the
 577         <filename>/dev/net/tun</filename> device.</para>
 578         </listitem>
 579       </varlistentry>
 580
 581     </variablelist>
 582
 583   </refsect1>
 584
 585   <refsect1>
 586     <title>[Tap] Section Options</title>
 587
 588     <para>The <literal>[Tap]</literal> section only applies for
 589     netdevs of kind <literal>tap</literal>, and accepts the same keys
 590     as the <literal>[Tun]</literal> section.</para>
 591   </refsect1>
 592
 593   <refsect1>
 594     <title>[Bond] Section Options</title>
 595
 596     <para>The <literal>[Bond]</literal> section accepts the following
 597     key:</para>
 598
 599     <variablelist class='network-directives'>
 600       <varlistentry>
 601         <term><varname>Mode=</varname></term>
 602         <listitem>
 603           <para>Specifies one of the bonding policies. The default is
 604           <literal>balance-rr</literal> (round robin). Possible values are
 605           <literal>balance-rr</literal>,
 606           <literal>active-backup</literal>,
 607           <literal>balance-xor</literal>,
 608           <literal>broadcast</literal>,
 609           <literal>802.3ad</literal>,
 610           <literal>balance-tlb</literal>, and
 611           <literal>balance-alb</literal>.
 612           </para>
 613         </listitem>
 614       </varlistentry>
 615
 616       <varlistentry>
 617         <term><varname>TransmitHashPolicy=</varname></term>
 618         <listitem>
 619           <para>Selects the transmit hash policy to use for slave
 620           selection in balance-xor, 802.3ad, and tlb modes. Possible
 621           values are
 622           <literal>layer2</literal>,
 623           <literal>layer3+4</literal>,
 624           <literal>layer2+3</literal>,
 625           <literal>encap2+3</literal>,
 626           <literal>802.3ad</literal>, and
 627           <literal>encap3+4</literal>.
 628           </para>
 629         </listitem>
 630       </varlistentry>
 631
 632       <varlistentry>
 633         <term><varname>LACPTransmitRate=</varname></term>
 634         <listitem>
 635           <para>Specifies the rate with which link partner transmits
 636           Link Aggregation Control Protocol Data Unit packets in
 637           802.3ad mode. Possible values are <literal>slow</literal>,
 638           which requests partner to transmit LACPDUs every 30 seconds,
 639           and <literal>fast</literal>, which requests partner to
 640           transmit LACPDUs every second. The default value is
 641           <literal>slow</literal>.</para>
 642         </listitem>
 643       </varlistentry>
 644
 645       <varlistentry>
 646         <term><varname>MIIMonitorSec=</varname></term>
 647         <listitem>
 648           <para>Specifies the frequency that Media Independent
 649           Interface link monitoring will occur. A value of zero
 650           disables MII link monitoring. This values is rounded down to
 651           the nearest millisecond. The default value is 0.</para>
 652         </listitem>
 653       </varlistentry>
 654
 655       <varlistentry>
 656         <term><varname>UpDelaySec=</varname></term>
 657         <listitem>
 658           <para>Specifies the delay before a link is enabled after a
 659           link up status has been detected. This value is rounded down
 660           to a multiple of MIIMonitorSec. The default value is
 661           0.</para>
 662         </listitem>
 663       </varlistentry>
 664
 665       <varlistentry>
 666         <term><varname>DownDelaySec=</varname></term>
 667         <listitem>
 668           <para>Specifies the delay before a link is disabled after a
 669           link down status has been detected. This value is rounded
 670           down to a multiple of MIIMonitorSec. The default value is
 671           0.</para>
 672         </listitem>
 673       </varlistentry>
 674
 675       <varlistentry>
 676         <term><varname>LearnPacketIntervalSec=</varname></term>
 677         <listitem>
 678           <para>Specifies the number of seconds between instances where the bonding
 679           driver sends learning packets to each slaves peer switch.
 680           The valid range is 1 - 0x7fffffff; the default value is 1. This Option
 681           has effect only in balance-tlb and balance-alb modes.</para>
 682         </listitem>
 683       </varlistentry>
 684
 685       <varlistentry>
 686         <term><varname>AdSelect=</varname></term>
 687         <listitem>
 688           <para>Specifies the 802.3ad aggregation selection logic to use. Possible values are
 689           <literal>stable</literal>,
 690           <literal>bandwidth</literal>,
 691           <literal>count</literal>
 692           </para>
 693         </listitem>
 694       </varlistentry>
 695
 696       <varlistentry>
 697         <term><varname>FailOverMACPolicy=</varname></term>
 698         <listitem>
 699           <para>Specifies whether active-backup mode should set all slaves to
 700           the same MAC address at enslavement or, when enabled, perform special handling of the
 701           bond's MAC address in accordance with the selected policy. The default policy is none.
 702           Possible values are
 703           <literal>none</literal>,
 704           <literal>active</literal>,
 705           <literal>follow</literal>
 706           </para>
 707         </listitem>
 708       </varlistentry>
 709
 710       <varlistentry>
 711         <term><varname>ARPValidate=</varname></term>
 712         <listitem>
 713           <para>Specifies whether or not ARP probes and replies should be
 714           validated in any mode that supports ARP monitoring, or whether
 715           non-ARP traffic should be filtered (disregarded) for link
 716           monitoring purposes. Possible values are
 717           <literal>none</literal>,
 718           <literal>active</literal>,
 719           <literal>backup</literal>,
 720           <literal>all</literal>
 721           </para>
 722         </listitem>
 723       </varlistentry>
 724
 725       <varlistentry>
 726         <term><varname>ARPIntervalSec=</varname></term>
 727         <listitem>
 728           <para>Specifies the ARP link monitoring frequency in milliseconds.
 729           A value of 0 disables ARP monitoring. The default value is 0.
 730           </para>
 731         </listitem>
 732       </varlistentry>
 733
 734       <varlistentry>
 735         <term><varname>ARPIPTargets=</varname></term>
 736         <listitem>
 737           <para>Specifies the IP addresses to use as ARP monitoring peers when
 738           ARPIntervalSec is greater than 0. These are the targets of the ARP request
 739           sent to determine the health of the link to the targets.
 740           Specify these values in ipv4 dotted decimal format. At least one IP
 741           address must be given for ARP monitoring to function. The
 742           maximum number of targets that can be specified is 16. The
 743           default value is no IP addresses.
 744           </para>
 745         </listitem>
 746       </varlistentry>
 747
 748       <varlistentry>
 749         <term><varname>ARPAllTargets=</varname></term>
 750         <listitem>
 751           <para>Specifies the quantity of ARPIPTargets that must be reachable
 752           in order for the ARP monitor to consider a slave as being up.
 753           This option affects only active-backup mode for slaves with
 754           ARPValidate enabled. Possible values are
 755           <literal>any</literal>,
 756           <literal>all</literal>
 757           </para>
 758         </listitem>
 759       </varlistentry>
 760
 761       <varlistentry>
 762         <term><varname>PrimaryReselectPolicy=</varname></term>
 763         <listitem>
 764           <para>Specifies the reselection policy for the primary slave.  This
 765           affects how the primary slave is chosen to become the active slave
 766           when failure of the active slave or recovery of the primary slave
 767           occurs. This option is designed to prevent flip-flopping between
 768           the primary slave and other slaves.  Possible values are
 769           <literal>always</literal>,
 770           <literal>better</literal>,
 771           <literal>failure</literal>
 772           </para>
 773         </listitem>
 774       </varlistentry>
 775
 776       <varlistentry>
 777         <term><varname>ResendIGMP=</varname></term>
 778         <listitem>
 779           <para>Specifies the number of IGMP membership reports to be issued after
 780           a failover event. One membership report is issued immediately after
 781           the failover, subsequent packets are sent in each 200ms interval.
 782           The valid range is (0 - 255). Defaults to 1. A value of 0
 783           prevents the IGMP membership report from being issued in response
 784           to the failover event.
 785           </para>
 786         </listitem>
 787       </varlistentry>
 788
 789       <varlistentry>
 790         <term><varname>PacketsPerSlave=</varname></term>
 791         <listitem>
 792           <para> Specify the number of packets to transmit through a slave before
 793             moving to the next one. When set to 0 then a slave is chosen at
 794             random.The valid range is (0 - 65535). Defaults to 1. This option
 795             has effect only in balance-rr mode.
 796           </para>
 797         </listitem>
 798       </varlistentry>
 799
 800       <varlistentry>
 801         <term><varname>GratuitousARP=</varname></term>
 802         <listitem>
 803           <para>Specify the number of peer notifications (gratuitous ARPs and
 804             unsolicited IPv6 Neighbor Advertisements) to be issued after a
 805             failover event.  As soon as the link is up on the new slave
 806             a peer notification is sent on the  bonding device and each
 807             VLAN sub-device.  This is repeated at each link monitor interval
 808             (ARPIntervalSec or MIIMonitorSec, whichever is active) if the number is
 809             greater than 1. The valid range is (0 - 255). Default value is 1.
 810             These options affect only the active-backup mode.
 811           </para>
 812         </listitem>
 813       </varlistentry>
 814
 815       <varlistentry>
 816         <term><varname>AllSlavesActive=</varname></term>
 817         <listitem>
 818           <para> A boolean. Specifies that duplicate frames (received on inactive ports)
 819           should be dropped false or delivered true. Normally, bonding will drop
 820           duplicate frames (received on inactive ports), which is desirable for
 821           most users. But there are some times it is nice to allow duplicate
 822           frames to be delivered. The default value is false (drop duplicate frames
 823           received on inactive ports).
 824           </para>
 825         </listitem>
 826       </varlistentry>
 827
 828       <varlistentry>
 829         <term><varname>MinLinks=</varname></term>
 830         <listitem>
 831           <para>Specifies the minimum number of links that must be active before
 832           asserting carrier. The default value is 0.
 833           </para>
 834         </listitem>
 835       </varlistentry>
 836
 837     </variablelist>
 838
 839     <para>For more detail information see
 840     <ulink url="https://www.kernel.org/doc/Documentation/networking/bonding.txt">
 841     Linux Ethernet Bonding Driver HOWTO</ulink></para>
 842
 843   </refsect1>
 844
 845   <refsect1>
 846     <title>Example</title>
 847     <example>
 848       <title>&pkgsysconfdir;/network/bridge.netdev</title>
 849
 850       <programlisting>[NetDev]
 851 Name=bridge0
 852 Kind=bridge</programlisting>
 853     </example>
 854
 855     <example>
 856       <title>&pkgsysconfdir;/network/vlan1.netdev</title>
 857
 858       <programlisting>[Match]
 859 Virtualization=no
 860
 861 [NetDev]
 862 Name=vlan1
 863 Kind=vlan
 864
 865 [VLAN]
 866 Id=1</programlisting>
 867     </example>
 868     <example>
 869       <title>&pkgsysconfdir;/network/ipip.netdev</title>
 870       <programlisting>[NetDev]
 871 Name=ipip-tun
 872 Kind=ipip
 873 MTUBytes=1480
 874
 875 [Tunnel]
 876 Local=192.168.223.238
 877 Remote=192.169.224.239
 878 TTL=64</programlisting>
 879     </example>
 880     <example>
 881       <title>&pkgsysconfdir;/network/tap.netdev</title>
 882       <programlisting>[NetDev]
 883 Name=tap-test
 884 Kind=tap
 885
 886 [Tap]
 887 MultiQueue=true
 888 PacketInfo=true</programlisting> </example>
 889
 890     <example>
 891       <title>&pkgsysconfdir;/network/sit.netdev</title>
 892       <programlisting>[NetDev]
 893 Name=sit-tun
 894 Kind=sit
 895 MTUBytes=1480
 896
 897 [Tunnel]
 898 Local=10.65.223.238
 899 Remote=10.65.223.239</programlisting>
 900     </example>
 901
 902     <example>
 903       <title>&pkgsysconfdir;/network/gre.netdev</title>
 904       <programlisting>[NetDev]
 905 Name=gre-tun
 906 Kind=gre
 907 MTUBytes=1480
 908
 909 [Tunnel]
 910 Local=10.65.223.238
 911 Remote=10.65.223.239</programlisting>
 912     </example>
 913
 914     <example>
 915       <title>&pkgsysconfdir;/network/vti.netdev</title>
 916
 917       <programlisting>[NetDev]
 918 Name=vti-tun
 919 Kind=vti
 920 MTUBytes=1480
 921
 922 [Tunnel]
 923 Local=10.65.223.238
 924 Remote=10.65.223.239</programlisting>
 925     </example>
 926
 927     <example>
 928       <title>&pkgsysconfdir;/network/veth.netdev</title>
 929       <programlisting>[NetDev]
 930 Name=veth-test
 931 Kind=veth
 932
 933 [Peer]
 934 Name=veth-peer</programlisting>
 935     </example>
 936
 937     <example>
 938       <title>&pkgsysconfdir;/network/dummy.netdev</title>
 939       <programlisting>[NetDev]
 940 Name=dummy-test
 941 Kind=dummy
 942 MACAddress=12:34:56:78:9a:bc</programlisting>
 943     </example>
 944
 945   </refsect1>
 946   <refsect1>
 947     <title>See Also</title>
 948     <para>
 949       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 950       <citerefentry><refentrytitle>systemd-networkd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 951       <citerefentry><refentrytitle>systemd.link</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 952       <citerefentry><refentrytitle>systemd.network</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 953     </para>
 954   </refsect1>
 955
 956 </refentry>