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<?xml version='1.0'?> <!--*-nxml-*-->
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
<!--
This file is part of systemd.
Copyright 2013 Tom Gundersen
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
-->
<refentry id="systemd.netdev" conditional='ENABLE_NETWORKD'>
<refentryinfo>
<title>systemd.network</title>
<productname>systemd</productname>
<authorgroup>
<author>
<contrib>Developer</contrib>
<firstname>Tom</firstname>
<surname>Gundersen</surname>
<email>teg@jklm.no</email>
</author>
</authorgroup>
</refentryinfo>
<refmeta>
<refentrytitle>systemd.netdev</refentrytitle>
<manvolnum>5</manvolnum>
</refmeta>
<refnamediv>
<refname>systemd.netdev</refname>
<refpurpose>Virtual Network Device configuration</refpurpose>
</refnamediv>
<refsynopsisdiv>
<para><filename><replaceable>netdev</replaceable>.netdev</filename></para>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para>Network setup is performed by
<citerefentry><refentrytitle>systemd-networkd</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
</para>
<para>Virtual Network Device files must have the extension
<filename>.netdev</filename>; other extensions are ignored. Virtual
network devices are created as soon as networkd is started.</para>
<para>The <filename>.netdev</filename> files are read from the files located in the
system network directory <filename>/usr/lib/systemd/network</filename>,
the volatile runtime network directory
<filename>/run/systemd/network</filename> and the local administration
network directory <filename>/etc/systemd/network</filename>.
All configuration files are collectively sorted and processed in lexical order,
regardless of the directories in which they live. However, files with
identical filenames replace each other. Files in
<filename>/etc</filename> have the highest priority, files in
<filename>/run</filename> take precedence over files with the same
name in <filename>/usr/lib</filename>. This can be used to override a
system-supplied configuration file with a local file if needed; a symlink in
<filename>/etc</filename> with the same name as a configuration file in
<filename>/usr/lib</filename>, pointing to <filename>/dev/null</filename>,
disables the configuration file entirely.</para>
</refsect1>
<refsect1>
<title>[Match] Section Options</title>
<para>A virtual network device is only created if the
<literal>[Match]</literal> section matches the current
environment, or if the section is empty. The following keys are accepted:</para>
<variablelist class='network-directives'>
<varlistentry>
<term><varname>Host=</varname></term>
<listitem>
<para>Matches against the hostname or machine ID of the
host. See <literal>ConditionHost=</literal> in
<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
for details.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>Virtualization=</varname></term>
<listitem>
<para>Checks whether the system is executed in a virtualized
environment and optionally test whether it is a specific
implementation. See <literal>ConditionVirtualization=</literal> in
<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
for details.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>KernelCommandLine=</varname></term>
<listitem>
<para>Checks whether a specific kernel command line option is
set (or if prefixed with the exclamation mark unset). See
<literal>ConditionKernelCommandLine=</literal> in
<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
for details.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>Architecture=</varname></term>
<listitem>
<para>Checks whether the system is running on a specific
architecture. See <literal>ConditionArchitecture=</literal> in
<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
for details.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>[NetDev] Section Options</title>
<para>The <literal>[NetDev]</literal> section accepts the following
keys:</para>
<variablelist class='network-directives'>
<varlistentry>
<term><varname>Description=</varname></term>
<listitem>
<para>A free-form description of the netdev.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>Name=</varname></term>
<listitem>
<para>The interface name used when creating the
netdev. This option is compulsory.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>Kind=</varname></term>
<listitem>
<para>The netdev kind. Currently, <literal>bridge</literal>,
<literal>bond</literal>, <literal>vlan</literal>,
<literal>macvlan</literal>, <literal>vxlan</literal>,
<literal>ipip</literal>, <literal>gre</literal>,
<literal>sit</literal>, <literal>vti</literal>,
<literal>veth</literal>, <literal>tun</literal>,
<literal>tap</literal> and <literal>dummy</literal>
are supported. This option is compulsory.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>MTUBytes=</varname></term>
<listitem>
<para>The maximum transmission unit in bytes to
set for the device. The usual suffixes K, M, G,
are supported and are understood to the base of
1024.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>MACAddress=</varname></term>
<listitem>
<para>The MAC address to use for the device.
If none is given, one is generated based on
the interface name and the
<citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>[VLAN] Section Options</title>
<para>The <literal>[VLAN]</literal> section only applies for netdevs of kind <literal>vlan</literal>,
and accepts the following key:</para>
<variablelist class='network-directives'>
<varlistentry>
<term><varname>Id=</varname></term>
<listitem>
<para>The VLAN ID to use. An integer in the range 0–4094.
This option is compulsory.</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>[MACVLAN] Section Options</title>
<para>The <literal>[MACVLAN]</literal> section only applies for netdevs of kind
<literal>macvlan</literal>, and accepts the following key:</para>
<variablelist class='network-directives'>
<varlistentry>
<term><varname>Mode=</varname></term>
<listitem>
<para>The MACVLAN mode to use. The supported options are
<literal>private</literal>, <literal>vepa</literal>,
<literal>bridge</literal> and <literal>passthru</literal>.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>[VXLAN] Section Options</title>
<para>The <literal>[VXLAN]</literal> section only applies for netdevs of kind
<literal>vxlan</literal>, and accepts the following key:</para>
<variablelist class='network-directives'>
<varlistentry>
<term><varname>Id=</varname></term>
<listitem>
<para>The VXLAN ID to use.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>Group=</varname></term>
<listitem>
<para>An assigned multicast group IP address.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>TOS=</varname></term>
<listitem>
<para>The Type Of Service byte value for a vxlan interface.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>TTL=</varname></term>
<listitem>
<para>A fixed Time To Live N on Virtual eXtensible Local Area Network packets.
N is a number in the range 1-255. 0 is a special value meaning that packets
inherit the TTL value.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>MacLearning=</varname></term>
<listitem>
<para>A boolean. When true, enables dynamic MAC learning
to discover remote MAC addresses.</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>[Tunnel] Section Options</title>
<para>The <literal>[Tunnel]</literal> section only applies for netdevs of kind
<literal>ipip</literal>, <literal>sit</literal>, <literal>gre</literal> and
<literal>vti</literal> and accepts the following keys:</para>
<variablelist class='network-directives'>
<varlistentry>
<term><varname>Local=</varname></term>
<listitem>
<para>A static local address for tunneled packets.
It must be an address on another interface of this host.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>Remote=</varname></term>
<listitem>
<para>The remote endpoint of the tunnel.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>TOS=</varname></term>
<listitem>
<para>The Type Of Service byte value for a tunnel interface.
For details about the TOS see the
<ulink url="http://tools.ietf.org/html/rfc1349">
Type of Service in the Internet Protocol Suite
</ulink> document.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>TTL=</varname></term>
<listitem>
<para>A fixed Time To Live N on tunneled packets.
N is a number in the range 1-255. 0 is a special value meaning that packets
inherit the TTL value. The default value for IPv4 tunnels is: inherit.
The default value for IPv6 tunnels is: 64.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>DiscoverPathMTU=</varname></term>
<listitem>
<para>A boolean. When true, enables Path MTU Discovery on the tunnel.</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>[Peer] Section Options</title>
<para>The <literal>[Peer]</literal> section only applies for netdevs of kind <literal>veth</literal>
and accepts the following key:</para>
<variablelist class='network-directives'>
<varlistentry>
<term><varname>Name=</varname></term>
<listitem>
<para>The interface name used when creating the netdev.
This option is compulsory.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>MACAddress=</varname></term>
<listitem>
<para>The peer MACAddress, if not set it is generated in the same
way as the MAC address of the main interface.</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>[Tun] Section Options</title>
<para>The <literal>[Tun]</literal> section only applies for netdevs of kind
<literal>tun</literal>, and accepts the following keys:</para>
<variablelist class='network-directives'>
<varlistentry>
<term><varname>OneQueue=</varname></term>
<listitem><para>Takes a boolean argument. Configures whether
all packets are queued at the device (enabled), or a fixed number
of packets are queued at the device and the rest at the
<literal>qdisc</literal>. Defaults to <literal>no</literal>.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>MultiQueue=</varname></term>
<listitem><para>Takes a boolean argument. Configures whether to
use multiple file descriptors (queues) to parallelize packets
sending and receiving. Defaults to <literal>no</literal>.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>PacketInfo=</varname></term>
<listitem><para>Takes a boolean argument. Configures whether packets
should be prepened with four extra bytes (two flag bytes and two
protocol bytes). If disabled it indicates that the packets will be
pure IP packets. Defaults to <literal>no</literal>.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>User=</varname></term>
<listitem><para>User to grant access to the <filename>/dev/net/tun</filename>
device.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>Group=</varname></term>
<listitem><para>Group to grant access to the <filename>/dev/net/tun</filename>
device.</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>[Tap] Section Options</title>
<para>The <literal>[Tap]</literal> section only applies for netdevs of kind
<literal>tap</literal>, and accepts the same keys as the
<literal>[Tun]</literal> section.</para>
</refsect1>
<refsect1>
<title>Example</title>
<example>
<title>/etc/systemd/network/bridge.netdev</title>
<programlisting>[NetDev]
Name=bridge0
Kind=bridge</programlisting>
</example>
<example>
<title>/etc/systemd/network/vlan1.netdev</title>
<programlisting>[Match]
Virtualization=no
[NetDev]
Name=vlan1
Kind=vlan
[VLAN]
Id=1</programlisting>
</example>
<example>
<title>/etc/systemd/network/ipip.netdev</title>
<programlisting>[NetDev]
Name=ipip-tun
Kind=ipip
MTUBytes=1480
[Tunnel]
Local=192.168.223.238
Remote=192.169.224.239
TTL=64</programlisting>
</example>
<example>
<title>/etc/systemd/network/tap.netdev</title>
<programlisting>[NetDev]
Name=tap-test
Kind=tap
[Tap]
MultiQueue=true
PacketInfo=true</programlisting> </example>
<example>
<title>/etc/systemd/network/sit.netdev</title>
<programlisting>[NetDev]
Name=sit-tun
Kind=sit
MTUBytes=1480
[Tunnel]
Local=10.65.223.238
Remote=10.65.223.239</programlisting>
</example>
<example>
<title>/etc/systemd/network/gre.netdev</title>
<programlisting>[NetDev]
Name=gre-tun
Kind=gre
MTUBytes=1480
[Tunnel]
Local=10.65.223.238
Remote=10.65.223.239</programlisting>
</example>
<example>
<title>/etc/systemd/network/vti.netdev</title>
<programlisting>[NetDev]
Name=vti-tun
Kind=vti
MTUBytes=1480
[Tunnel]
Local=10.65.223.238
Remote=10.65.223.239</programlisting>
</example>
<example>
<title>/etc/systemd/network/veth.netdev</title>
<programlisting>[NetDev]
Name=veth-test
Kind=veth
[Peer]
Name=veth-peer</programlisting>
</example>
<example>
<title>/etc/systemd/network/dummy.netdev</title>
<programlisting>[NetDev]
Name=dummy-test
Kind=dummy
MACAddress=12:34:56:78:9a:bc</programlisting>
</example>
</refsect1>
<refsect1>
<title>See Also</title>
<para>
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd-networkd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd.network</refentrytitle><manvolnum>5</manvolnum></citerefentry>
</para>
</refsect1>
</refentry>
|