2 <!DOCTYPE refentry PUBLIC
"-//OASIS//DTD DocBook XML V4.2//EN"
3 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
6 SPDX-License-Identifier: LGPL-2.1+
8 Copyright © 2014 Vinay Kulkarni
11 <refentry id=
"networkd.conf" conditional='ENABLE_NETWORKD'
12 xmlns:
xi=
"http://www.w3.org/2001/XInclude">
14 <title>networkd.conf
</title>
15 <productname>systemd
</productname>
19 <refentrytitle>networkd.conf
</refentrytitle>
20 <manvolnum>5</manvolnum>
24 <refname>networkd.conf
</refname>
25 <refname>networkd.conf.d
</refname>
26 <refpurpose>Global Network configuration files
</refpurpose>
30 <para><filename>/etc/systemd/networkd.conf
</filename></para>
31 <para><filename>/etc/systemd/networkd.conf.d/*.conf
</filename></para>
32 <para><filename>/usr/lib/systemd/networkd.conf.d/*.conf
</filename></para>
36 <title>Description
</title>
38 <para>These configuration files control global network parameters.
39 Currently the DHCP Unique Identifier (DUID).
</para>
43 <xi:include href=
"standard-conf.xml" xpointer=
"main-conf" />
46 <title>[DHCP] Section Options
</title>
48 <para>This section configures the DHCP Unique Identifier (DUID) value used by DHCP
49 protocol. DHCPv6 client protocol sends the DHCP Unique Identifier and the interface
50 Identity Association Identifier (IAID) to a DHCP server when acquiring a dynamic IPv6
51 address. DHCPv4 client protocol sends IAID and DUID to the DHCP server when acquiring
52 a dynamic IPv4 address if
<option>ClientIdentifier=duid
</option>. IAID and DUID allows
53 a DHCP server to uniquely identify the machine and the interface requesting a DHCP IP.
54 To configure IAID and ClientIdentifier, see
55 <citerefentry><refentrytitle>systemd.network
</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
58 <para>The following options are understood:
</para>
60 <variablelist class='network-directives'
>
62 <term><varname>DUIDType=
</varname></term>
63 <listitem><para>Specifies how the DUID should be generated. See
64 <ulink url=
"https://tools.ietf.org/html/rfc3315#section-9">RFC
3315</ulink>
65 for a description of all the options.
</para>
67 <para>The following values are understood:
70 <term><option>vendor
</option></term>
71 <listitem><para>If
<literal>DUIDType=vendor
</literal>, then the DUID value will be generated using
72 <literal>43793</literal> as the vendor identifier (systemd) and hashed contents of
73 <citerefentry><refentrytitle>machine-id
</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
74 This is the default if
<varname>DUIDType=
</varname> is not specified.
79 <term><option>uuid
</option></term>
80 <listitem><para>If
<literal>DUIDType=uuid
</literal>, and
<varname>DUIDRawData=
</varname> is not set,
81 then the product UUID is used as a DUID value. If a system does not have valid product UUID, then
82 an application-specific
83 <citerefentry><refentrytitle>machine-id
</refentrytitle><manvolnum>5</manvolnum></citerefentry>
84 is used as a DUID value. About the application-specific machine ID, see
85 <citerefentry><refentrytitle>sd_id128_get_machine_app_specific
</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
90 <term><option>link-layer-time[:
<replaceable>TIME
</replaceable>]
</option></term>
91 <term><option>link-layer
</option></term>
92 <listitem><para>If
<literal>link-layer-time
</literal> or
<literal>link-layer
</literal> is specified,
93 then the MAC address of the interface is used as a DUID value. The value
<literal>link-layer-time
</literal>
94 can take additional time value after a colon, e.g.
<literal>link-layer-time:
2018-
01-
23 12:
34:
56 UTC
</literal>.
95 The default time value is
<literal>2000-
01-
01 00:
00:
00 UTC
</literal>.
101 <para>In all cases,
<varname>DUIDRawData=
</varname> can be used to override the
102 actual DUID value that is used.
</para></listitem>
106 <term><varname>DUIDRawData=
</varname></term>
107 <listitem><para>Specifies the DHCP DUID value as a single newline-terminated, hexadecimal string, with each
108 byte separated by
<literal>:
</literal>. The DUID that is sent is composed of the DUID type specified by
109 <varname>DUIDType=
</varname> and the value configured here.
</para>
111 <para>The DUID value specified here overrides the DUID that
112 <citerefentry><refentrytitle>systemd-networkd.service
</refentrytitle><manvolnum>8</manvolnum></citerefentry>
113 generates from the machine ID. To configure DUID per-network, see
114 <citerefentry><refentrytitle>systemd.network
</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
115 The configured DHCP DUID should conform to the specification in
116 <ulink url=
"http://tools.ietf.org/html/rfc3315#section-9">RFC
3315</ulink>,
117 <ulink url=
"http://tools.ietf.org/html/rfc6355">RFC
6355</ulink>. To configure IAID, see
118 <citerefentry><refentrytitle>systemd.network
</refentrytitle><manvolnum>5</manvolnum>
119 </citerefentry>.
</para>
122 <title>A
<option>DUIDType=vendor
</option> with a custom value
</title>
124 <programlisting>DUIDType=vendor
125 DUIDRawData=
00:
00:ab:
11:f9:
2a:c2:
77:
29:f9:
5c:
00</programlisting>
127 <para>This specifies a
14 byte DUID, with the type DUID-EN (
<literal>00:
02</literal>), enterprise number
128 43793 (
<literal>00:
00:ab:
11</literal>), and identifier value
<literal>f9:
2a:c2:
77:
29:f9:
5c:
00</literal>.
137 <title>See Also
</title>
139 <citerefentry><refentrytitle>systemd
</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
140 <citerefentry><refentrytitle>systemd.network
</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
141 <citerefentry><refentrytitle>systemd-networkd.service
</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
142 <citerefentry><refentrytitle>machine-id
</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
143 <citerefentry><refentrytitle>sd_id128_get_machine_app_specific
</refentrytitle><manvolnum>3</manvolnum></citerefentry>