schemes". The default naming scheme is chosen at compilation time. Usually this will be the latest
implemented version, but it is also possible to set one of the older versions to preserve
compatibility. This may be useful for example for distributions, which may introduce new versions of
- systemd in stable releases without changing the naming scheme. The naming scheme may also be overriden
+ systemd in stable releases without changing the naming scheme. The naming scheme may also be overridden
using the <varname>net.naming-scheme=</varname> kernel command line switch, see
<citerefentry><refentrytitle>systemd-udevd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
Available naming schemes are described below.</para>
- <para>After the udev proprties have been generated, appropriate udev rules may be used to actually rename
+ <para>After the udev properties have been generated, appropriate udev rules may be used to actually rename
devices based on those properties. See the description of <varname>NamePolicy=</varname> and
<varname>MACAddressPolicy=</varname> in
<citerefentry><refentrytitle>systemd.link</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
+
+ <para>Note that while the concept of network interface naming schemes is primarily relevant in the
+ context of <filename>systemd-udevd.service</filename>, the
+ <citerefentry><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+ container manager also takes it into account when naming network interfaces, see below.</para>
</refsect1>
<refsect1>
</row>
<row>
<entry><constant>sl</constant></entry>
- <entry>serial line IP (slip)</entry>
+ <entry>Serial line IP (slip)</entry>
</row>
<row>
<entry><constant>wl</constant></entry>
<varlistentry>
<term><varname>ID_NET_NAME_ONBOARD=<replaceable>prefix</replaceable><constant>o</constant><replaceable>number</replaceable></varname></term>
- <listitem><para>This name is set based on the ordering information given by the firmware for
- on-board devices. The name consists of the prefix, letter <constant>o</constant>, and a number
+ <listitem><para>This name is set based on the numeric ordering information given by the firmware
+ for on-board devices. The name consists of the prefix, letter <constant>o</constant>, and a number
specified by the firmware. This is only available for PCI devices.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>ID_NET_LABEL_ONBOARD=<replaceable>prefix</replaceable> <replaceable>label</replaceable></varname></term>
- <listitem><para>This property is set based on label given by the firmware for on-board devices. The
- name consists of the prefix concatenated with the label. This is only available for PCI devices.
+ <listitem><para>This property is set based on textual label given by the firmware for on-board
+ devices. The name consists of the prefix concatenated with the label. This is only available for
+ PCI devices.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>ID_NET_NAME_SLOT=<replaceable>prefix</replaceable>[<constant>P</constant><replaceable>domain</replaceable>]<constant>s</constant><replaceable>slot</replaceable>[<constant>f</constant><replaceable>function</replaceable>][<constant>n</constant><replaceable>port_name</replaceable>|<constant>d</constant><replaceable>dev_port</replaceable>]</varname></term>
+ <term><varname>ID_NET_NAME_SLOT=<replaceable>prefix</replaceable><constant>v</constant><replaceable>slot</replaceable></varname></term>
<term><varname>ID_NET_NAME_SLOT=<replaceable>prefix</replaceable>[<constant>P</constant><replaceable>domain</replaceable>]<constant>s</constant><replaceable>slot</replaceable>[<constant>f</constant><replaceable>function</replaceable>][<constant>n</constant><replaceable>port_name</replaceable>|<constant>d</constant><replaceable>dev_port</replaceable>]<constant>b</constant><replaceable>number</replaceable></varname></term>
<term><varname>ID_NET_NAME_SLOT=<replaceable>prefix</replaceable>[<constant>P</constant><replaceable>domain</replaceable>]<constant>s</constant><replaceable>slot</replaceable>[<constant>f</constant><replaceable>function</replaceable>][<constant>n</constant><replaceable>port_name</replaceable>|<constant>d</constant><replaceable>dev_port</replaceable>]<constant>u</constant><replaceable>port</replaceable>…[<constant>c</constant><replaceable>config</replaceable>][<constant>i</constant><replaceable>interface</replaceable>]</varname></term>
<term><varname>ID_NET_NAME_SLOT=<replaceable>prefix</replaceable>[<constant>P</constant><replaceable>domain</replaceable>]<constant>s</constant><replaceable>slot</replaceable>[<constant>f</constant><replaceable>function</replaceable>][<constant>n</constant><replaceable>port_name</replaceable>|<constant>d</constant><replaceable>dev_port</replaceable>]<constant>v</constant><replaceable>slot</replaceable></varname></term>
<listitem><para>This property describes the slot position. Different schemes are used depending on
- the bus type, as described in the table below. In all cases, PCI slot information must be known. In
- case of USB, BCMA, and SR-VIO devices, the full name consists of the prefix, PCI slot identifier,
- and USB or BCMA or SR-VIO slot identifier. The first two parts are denoted as "…" in the table
- below.</para>
+ the bus type, as described in the table below. In case of USB, BCMA, and SR-VIO devices, the full
+ name consists of the prefix, PCI slot identifier, and USB or BCMA or SR-VIO slot identifier. The
+ first two parts are denoted as "…" in the table below.</para>
<table>
<title>Slot naming schemes</title>
<entry>PCI slot number</entry>
</row>
+ <row>
+ <entry><replaceable>prefix</replaceable> <constant>v</constant><replaceable>slot</replaceable></entry>
+ <entry>VIO slot number (IBM PowerVM)</entry>
+ </row>
+
<row>
<entry>… <constant>b</constant><replaceable>number</replaceable></entry>
<entry>Broadcom bus (BCMA) core number</entry>
<para>For USB devices the full chain of port numbers of hubs is composed. If the name gets longer
than the maximum number of 15 characters, the name is not exported. The usual USB configuration
number 1 and interface number 0 values are suppressed.</para>
- </listitem>
<para>SR-IOV virtual devices are named based on the name of the parent interface, with a suffix of
<constant>v</constant> and the virtual device number, with any leading zeros removed. The bus
- number is ignored. This device type is found in IBM PowerVMs.</para>
+ number is ignored.</para>
+ </listitem>
</varlistentry>
<varlistentry>
<varlistentry>
<term><constant>v238</constant></term>
- <listitem><para>This is the naming naming that was implemented in systemd 238.</para></listitem>
+ <listitem><para>This is the naming scheme that was implemented in systemd 238.</para></listitem>
</varlistentry>
<varlistentry>
again. Previously, this naming policy applied implicitly, and now it must be explicitly
requested. Effectively, this means that network devices will be renamed according to the
configuration, even if they have been renamed already, if <constant>keep</constant> is not
- specified as the naming policy in the <filename noindex='true'>.link</filename> file. See
+ specified as the naming policy in the <filename index="false">.link</filename> file. See
<citerefentry><refentrytitle>systemd.link</refentrytitle><manvolnum>5</manvolnum></citerefentry>
for a description of <varname>NamePolicy=</varname>.</para></listitem>
</varlistentry>
<listitem><para><option>MACAddressPolicy=persistent</option> was extended to set MAC addresses
based on the device name. Previously addresses were only based on the
- <varname noindex='true'>ID_NET_NAME_*</varname> attributes, which meant that interface names would
+ <varname index="false">ID_NET_NAME_*</varname> attributes, which meant that interface names would
never be generated for virtual devices. Now a persistent address will be generated for most
devices, including in particular bridges.</para>
<para>Previously two-letter interface type prefix was prepended to
<varname>ID_NET_LABEL_ONBOARD=</varname>. This is not done anymore.</para></listitem>
</varlistentry>
- </variablelist>
+
+ <varlistentry>
+ <term><constant>v245</constant></term>
+
+ <listitem><para>When
+ <citerefentry><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+ derives the name for the host side of the network interface created with
+ <option>--network-veth</option> from the container name it previously simply truncated the result
+ at 15 characters if longer (since that's the maximum length for network interface names). From now
+ on, for any interface name that would be longer than 15 characters the last 4 characters are set to
+ a 24bit hash value of the full interface name. This way network interface name collisions between
+ multiple similarly named containers (who only differ in container name suffix) should be less
+ likely (but still possible, since the 24bit hash value is very small).</para></listitem>
+ </varlistentry>
+ </variablelist>
<para>Note that <constant>latest</constant> may be used to denote the latest scheme known (to this
- particular version of systemd.</para>
+ particular version of systemd).</para>
</refsect1>
<refsect1>
<para>
<citerefentry><refentrytitle>udev</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
<citerefentry><refentrytitle>udevadm</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
- <ulink url="https://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames">the
- original page describing stable interface names</ulink>
+ <ulink url="https://systemd.io/PREDICTABLE_INTERFACE_NAMES">Predictable Network Interface Names</ulink>,
+ <citerefentry><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry>
</para>
</refsect1>
projects / thirdparty / systemd.git / blobdiff