diff options
Diffstat (limited to 'man/systemd.link.xml')
| -rw-r--r-- | man/systemd.link.xml | 687 |
1 files changed, 687 insertions, 0 deletions
diff --git a/man/systemd.link.xml b/man/systemd.link.xml new file mode 100644 index 0000000..178f9b8 --- /dev/null +++ b/man/systemd.link.xml @@ -0,0 +1,687 @@ +<?xml version='1.0'?> +<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" + "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> + +<!-- + SPDX-License-Identifier: LGPL-2.1+ +--> + +<refentry id="systemd.link"> + <refentryinfo> + <title>systemd.link</title> + <productname>systemd</productname> + </refentryinfo> + + <refmeta> + <refentrytitle>systemd.link</refentrytitle> + <manvolnum>5</manvolnum> + </refmeta> + + <refnamediv> + <refname>systemd.link</refname> + <refpurpose>Network device configuration</refpurpose> + </refnamediv> + + <refsynopsisdiv> + <para><filename><replaceable>link</replaceable>.link</filename></para> + </refsynopsisdiv> + + <refsect1> + <title>Description</title> + + <para>Network link configuration is performed by the + <command>net_setup_link</command> udev builtin.</para> + + <para>The link 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>. Link files must have + the extension <filename>.link</filename>; other extensions are + ignored. All link 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 link file with a local file if needed. + As a special case, an empty file (file size 0) or symlink with the + same name pointing to <filename>/dev/null</filename> disables the + configuration file entirely (it is "masked").</para> + + <para>The link file contains a [Match] section, which determines if a given link file may be applied to a + given device, as well as a [Link] section specifying how the device should be configured. The first (in + lexical order) of the link files that matches a given device is applied. Note that a default file + <filename>99-default.link</filename> is shipped by the system. Any user-supplied + <filename>.link</filename> should hence have a lexically earlier name to be considered at all.</para> + + <para>See <citerefentry><refentrytitle>udevadm</refentrytitle><manvolnum>8</manvolnum></citerefentry> for + diagnosing problems with <filename>.link</filename> files.</para> + </refsect1> + + <refsect1> + <title>[Match] Section Options</title> + + <para>A link file is said to match a device if each of the entries in the [Match] section matches, or if + the section is empty. The following keys are accepted:</para> + + <variablelist class='network-directives'> + <varlistentry> + <term><varname>MACAddress=</varname></term> + <listitem> + <para>A whitespace-separated list of hardware addresses. Use full colon-, hyphen- or dot-delimited hexadecimal. See the example below. + This option may appear more than once, in which case the lists are merged. If the empty string is assigned to this option, the list + of hardware addresses defined prior to this is reset.</para> + + <para>Example: + <programlisting>MACAddress=01:23:45:67:89:ab 00-11-22-33-44-55 AABB.CCDD.EEFF</programlisting></para> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>OriginalName=</varname></term> + <listitem> + <para>A whitespace-separated list of shell-style globs matching + the device name, as exposed by the udev property + "INTERFACE". This cannot be used to match on names that have + already been changed from userspace. Caution is advised when matching on + kernel-assigned names, as they are known to be unstable + between reboots.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>Path=</varname></term> + <listitem> + <para>A whitespace-separated list of shell-style globs matching + the persistent path, as exposed by the udev property + <varname>ID_PATH</varname>.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>Driver=</varname></term> + <listitem> + <para>A whitespace-separated list of shell-style globs matching the driver currently bound to the + device, as exposed by the udev property <varname>DRIVER</varname> of its parent device, or if that + is not set, the driver as exposed by <command>ethtool -i</command> of the device itself.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>Type=</varname></term> + <listitem> + <para>A whitespace-separated list of shell-style globs matching + the device type, as exposed by the udev + property <varname>DEVTYPE</varname>.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>Host=</varname></term> + <listitem> + <para>Matches against the hostname or machine + ID of the host. See <varname>ConditionHost=</varname> 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 + <varname>ConditionVirtualization=</varname> 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 + <varname>ConditionKernelCommandLine=</varname> in + <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry> + for details.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>KernelVersion=</varname></term> + <listitem> + <para>Checks whether the kernel version (as reported by <command>uname -r</command>) matches a certain + expression (or if prefixed with the exclamation mark does not match it). See + <varname>ConditionKernelVersion=</varname> 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 <varname>ConditionArchitecture=</varname> + in + <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry> + for details.</para> + </listitem> + </varlistentry> + </variablelist> + + </refsect1> + + <refsect1> + <title>[Link] Section Options</title> + + <para>The [Link] section accepts the following + keys:</para> + + <variablelist class='network-directives'> + <varlistentry> + <term><varname>Description=</varname></term> + <listitem> + <para>A description of the device.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>Alias=</varname></term> + <listitem> + <para>The <varname>ifalias</varname> interface property is set to this value.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>MACAddressPolicy=</varname></term> + <listitem> + <para>The policy by which the MAC address should be set. The + available policies are: + </para> + + <variablelist> + <varlistentry> + <term><option>persistent</option></term> + <listitem> + <para>If the hardware has a persistent MAC address, as + most hardware should, and if it is used by the kernel, + nothing is done. Otherwise, a new MAC address is + generated which is guaranteed to be the same on every + boot for the given machine and the given device, but + which is otherwise random. This feature depends on ID_NET_NAME_* + properties to exist for the link. On hardware where these + properties are not set, the generation of a persistent MAC address + will fail.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><option>random</option></term> + <listitem> + <para>If the kernel is using a random MAC address, + nothing is done. Otherwise, a new address is randomly + generated each time the device appears, typically at + boot. Either way, the random address will have the + <literal>unicast</literal> and + <literal>locally administered</literal> bits set.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><option>none</option></term> + <listitem> + <para>Keeps the MAC address assigned by the kernel.</para> + </listitem> + </varlistentry> + </variablelist> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>MACAddress=</varname></term> + <listitem> + <para>The MAC address to use, if no + <varname>MACAddressPolicy=</varname> + is specified.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>NamePolicy=</varname></term> + <listitem> + <para>An ordered, space-separated list of policies by which the interface name should be set. + <varname>NamePolicy=</varname> may be disabled by specifying <option>net.ifnames=0</option> on the + kernel command line. Each of the policies may fail, and the first successful one is used. The name + is not set directly, but is exported to udev as the property <option>ID_NET_NAME</option>, which + is, by default, used by a udev rule to set <varname>NAME</varname>. The available policies are: + </para> + + <variablelist> + <varlistentry> + <term><option>kernel</option></term> + <listitem> + <para>If the kernel claims that the name it has set + for a device is predictable, then no renaming is + performed.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><option>database</option></term> + <listitem> + <para>The name is set based on entries in the udev's + Hardware Database with the key + <varname>ID_NET_NAME_FROM_DATABASE</varname>. + </para> + </listitem> + </varlistentry> + <varlistentry> + <term><option>onboard</option></term> + <listitem> + <para>The name is set based on information given by + the firmware for on-board devices, as exported by the + udev property <varname>ID_NET_NAME_ONBOARD</varname>. + </para> + </listitem> + </varlistentry> + <varlistentry> + <term><option>slot</option></term> + <listitem> + <para>The name is set based on information given by + the firmware for hot-plug devices, as exported by the + udev property <varname>ID_NET_NAME_SLOT</varname>. + </para> + </listitem> + </varlistentry> + <varlistentry> + <term><option>path</option></term> + <listitem> + <para>The name is set based on the device's physical + location, as exported by the udev property + <varname>ID_NET_NAME_PATH</varname>.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><option>mac</option></term> + <listitem> + <para>The name is set based on the device's persistent + MAC address, as exported by the udev property + <varname>ID_NET_NAME_MAC</varname>.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><option>keep</option></term> + <listitem> + <para>If the device already had a name given by userspace (as part of creation of the device + or a rename), keep it.</para> + </listitem> + </varlistentry> + </variablelist> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>Name=</varname></term> + <listitem> + <para>The interface name to use in case all the + policies specified in + <varname>NamePolicy=</varname> fail, or in case + <varname>NamePolicy=</varname> is missing or + disabled.</para> + + <para>Note that specifying a name that the kernel might use for another + interface (for example <literal>eth0</literal>) is dangerous because the + name assignment done by udev will race with the assignment done by the + kernel, and only one interface may use the name. Depending on the order of + operations, either udev or the kernel will win, making the naming + unpredictable. It is best to use some different prefix, for example + <literal>internal0</literal>/<literal>external0</literal> or + <literal>lan0</literal>/<literal>lan1</literal>/<literal>lan3</literal>. + </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>BitsPerSecond=</varname></term> + <listitem> + <para>The speed to set for the device, the value is rounded + down to the nearest Mbps. The usual suffixes K, M, G, are + supported and are understood to the base of 1000.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>Duplex=</varname></term> + <listitem> + <para>The duplex mode to set for the device. The accepted values are <option>half</option> and + <option>full</option>.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>AutoNegotiation=</varname></term> + <listitem> + <para>Takes a boolean. If set to yes, automatic negotiation of transmission parameters is enabled. + Autonegotiation is a procedure by which two connected ethernet devices choose + common transmission parameters, such as speed, duplex mode, and flow control. + When unset, the kernel's default will be used.</para> + + <para>Note that if autonegotiation is enabled, speed and duplex settings are + read-only. If autonegotation is disabled, speed and duplex settings are writable + if the driver supports multiple link modes.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>WakeOnLan=</varname></term> + <listitem> + <para>The Wake-on-LAN policy to set for the device. The + supported values are:</para> + + <variablelist> + <varlistentry> + <term><option>phy</option></term> + <listitem> + <para>Wake on PHY activity.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><option>unicast</option></term> + <listitem> + <para>Wake on unicast messages.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><option>multicast</option></term> + <listitem> + <para>Wake on multicast messages.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><option>broadcast</option></term> + <listitem> + <para>Wake on broadcast messages.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><option>arp</option></term> + <listitem> + <para>Wake on ARP.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><option>magic</option></term> + <listitem> + <para>Wake on receipt of a magic packet. + </para> + </listitem> + </varlistentry> + <varlistentry> + <term><option>secureon</option></term> + <listitem> + <para>Enable secureon(tm) password for MagicPacket(tm). + </para> + </listitem> + </varlistentry> + <varlistentry> + <term><option>off</option></term> + <listitem> + <para>Never wake.</para> + </listitem> + </varlistentry> + </variablelist> + + <para>Defaults to <option>off</option>.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>Port=</varname></term> + <listitem> + <para>The port option is used to select the device port. The + supported values are:</para> + + <variablelist> + <varlistentry> + <term><option>tp</option></term> + <listitem> + <para>An Ethernet interface using Twisted-Pair cable as the medium.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><option>aui</option></term> + <listitem> + <para>Attachment Unit Interface (AUI). Normally used with hubs. + </para> + </listitem> + </varlistentry> + <varlistentry> + <term><option>bnc</option></term> + <listitem> + <para>An Ethernet interface using BNC connectors and co-axial cable.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><option>mii</option></term> + <listitem> + <para>An Ethernet interface using a Media Independent Interface (MII).</para> + </listitem> + </varlistentry> + <varlistentry> + <term><option>fibre</option></term> + <listitem> + <para>An Ethernet interface using Optical Fibre as the medium.</para> + </listitem> + </varlistentry> + </variablelist> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>Advertise=</varname></term> + <listitem> + <para>This sets what speeds and duplex modes of operation are advertised for auto-negotiation. + This implies <literal>AutoNegotiation=yes</literal>. The supported values are: + + <table> + <title>Supported advertise values</title> + <tgroup cols='3'> + <colspec colname='Advertise' /> + <colspec colname='Speed' /> + <colspec colname='Duplex Mode' /> + + <thead><row> + <entry>Advertise</entry> + <entry>Speed (Mbps)</entry> + <entry>Duplex Mode</entry> + </row></thead> + <tbody> + <row><entry><option>10baset-half</option></entry> + <entry>10</entry><entry>half</entry></row> + + <row><entry><option>10baset-full</option></entry> + <entry>10</entry><entry>full</entry></row> + + <row><entry><option>100baset-half</option></entry> + <entry>100</entry><entry>half</entry></row> + + <row><entry><option>100baset-full</option></entry> + <entry>100</entry><entry>full</entry></row> + + <row><entry><option>1000baset-half</option></entry> + <entry>1000</entry><entry>half</entry></row> + + <row><entry><option>1000baset-full</option></entry> + <entry>1000</entry><entry>full</entry></row> + + <row><entry><option>10000baset-full</option></entry> + <entry>10000</entry><entry>full</entry></row> + + <row><entry><option>2500basex-full</option></entry> + <entry>2500</entry><entry>full</entry></row> + + <row><entry><option>1000basekx-full</option></entry> + <entry>1000</entry><entry>full</entry></row> + + <row><entry><option>10000basekx4-full</option></entry> + <entry>10000</entry><entry>full</entry></row> + + <row><entry><option>10000basekr-full</option></entry> + <entry>10000</entry><entry>full</entry></row> + + <row><entry><option>10000baser-fec</option></entry> + <entry>10000</entry><entry>full</entry></row> + + <row><entry><option>20000basemld2-full</option></entry> + <entry>20000</entry><entry>full</entry></row> + + <row><entry><option>20000basekr2-full</option></entry> + <entry>20000</entry><entry>full</entry></row> + </tbody> + </tgroup> + </table> + + By default this is unset, i.e. all possible modes will be advertised. + This option may be specified more than once, in which case all specified speeds and modes are advertised. + If the empty string is assigned to this option, the list is reset, and all prior assignments have no effect. + </para> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>TCPSegmentationOffload=</varname></term> + <listitem> + <para>Takes a boolean. If set to true, the TCP Segmentation Offload (TSO) is enabled. + When unset, the kernel's default will be used.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>TCP6SegmentationOffload=</varname></term> + <listitem> + <para>Takes a boolean. If set to true, the TCP6 Segmentation Offload (tx-tcp6-segmentation) is enabled. + When unset, the kernel's default will be used.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>GenericSegmentationOffload=</varname></term> + <listitem> + <para>Takes a boolean. If set to true, the Generic Segmentation Offload (GSO) is enabled. + When unset, the kernel's default will be used.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>GenericReceiveOffload=</varname></term> + <listitem> + <para>Takes a boolean. If set to true, the Generic Receive Offload (GRO) is enabled. + When unset, the kernel's default will be used.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>LargeReceiveOffload=</varname></term> + <listitem> + <para>Takes a boolean. If set to true, the Large Receive Offload (LRO) is enabled. + When unset, the kernel's default will be used.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>RxChannels=</varname></term> + <listitem> + <para>Sets the number of receive channels (a number between 1 and 4294967295) .</para> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>TxChannels=</varname></term> + <listitem> + <para>Sets the number of transmit channels (a number between 1 and 4294967295).</para> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>OtherChannels=</varname></term> + <listitem> + <para>Sets the number of other channels (a number between 1 and 4294967295).</para> + </listitem> + </varlistentry> + <varlistentry> + <term><varname>CombinedChannels=</varname></term> + <listitem> + <para>Sets the number of combined set channels (a number between 1 and 4294967295).</para> + </listitem> + </varlistentry> + </variablelist> + </refsect1> + + <refsect1> + <title>Examples</title> + + <example> + <title>/usr/lib/systemd/network/99-default.link</title> + + <para>The link file <filename>99-default.link</filename> that is + shipped with systemd defines the default naming policy for + links.</para> + + <programlisting>[Link] +NamePolicy=kernel database onboard slot path +MACAddressPolicy=persistent</programlisting> + </example> + + <example> + <title>/etc/systemd/network/10-dmz.link</title> + + <para>This example assigns the fixed name + <literal>dmz0</literal> to the interface with the MAC address + 00:a0:de:63:7a:e6:</para> + + <programlisting>[Match] +MACAddress=00:a0:de:63:7a:e6 + +[Link] +Name=dmz0</programlisting> + </example> + + <example> + <title>/etc/systemd/network/10-internet.link</title> + + <para>This example assigns the fixed name + <literal>internet0</literal> to the interface with the device + path <literal>pci-0000:00:1a.0-*</literal>:</para> + + <programlisting>[Match] +Path=pci-0000:00:1a.0-* + +[Link] +Name=internet0</programlisting> + </example> + + <example> + <title>/etc/systemd/network/25-wireless.link</title> + + <para>Here's an overly complex example that shows the use of a large number of [Match] and [Link] settings.</para> + + <programlisting>[Match] +MACAddress=12:34:56:78:9a:bc +Driver=brcmsmac +Path=pci-0000:02:00.0-* +Type=wlan +Virtualization=no +Host=my-laptop +Architecture=x86-64 + +[Link] +Name=wireless0 +MTUBytes=1450 +BitsPerSecond=10M +WakeOnLan=magic +MACAddress=cb:a9:87:65:43:21</programlisting> + </example> + </refsect1> + + <refsect1> + <title>See Also</title> + <para> + <citerefentry> + <refentrytitle>systemd-udevd.service</refentrytitle><manvolnum>8</manvolnum> + </citerefentry>, + <citerefentry> + <refentrytitle>udevadm</refentrytitle><manvolnum>8</manvolnum> + </citerefentry>, + <citerefentry> + <refentrytitle>systemd.netdev</refentrytitle><manvolnum>5</manvolnum> + </citerefentry>, + <citerefentry> + <refentrytitle>systemd.network</refentrytitle><manvolnum>5</manvolnum> + </citerefentry> + </para> + </refsect1> + +</refentry> |