man/systemd.link.xml

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   8
   9 <refentry id="systemd.link">
  10   <refentryinfo>
  11     <title>systemd.link</title>
  12     <productname>systemd</productname>
  13   </refentryinfo>
  14
  15   <refmeta>
  16     <refentrytitle>systemd.link</refentrytitle>
  17     <manvolnum>5</manvolnum>
  18   </refmeta>
  19
  20   <refnamediv>
  21     <refname>systemd.link</refname>
  22     <refpurpose>Network device configuration</refpurpose>
  23   </refnamediv>
  24
  25   <refsynopsisdiv>
  26     <para><filename><replaceable>link</replaceable>.link</filename></para>
  27   </refsynopsisdiv>
  28
  29   <refsect1>
  30     <title>Description</title>
  31
  32     <para>Network link configuration is performed by the
  33     <command>net_setup_link</command> udev builtin.</para>
  34
  35     <para>The link files are read from the files located in the system
  36     network directory <filename>/usr/lib/systemd/network</filename>,
  37     the volatile runtime network directory
  38     <filename>/run/systemd/network</filename>, and the local
  39     administration network directory
  40     <filename>/etc/systemd/network</filename>. Link files must have
  41     the extension <filename>.link</filename>; other extensions are
  42     ignored. All link files are collectively sorted and processed in
  43     lexical order, regardless of the directories in which they live.
  44     However, files with identical filenames replace each other. Files
  45     in <filename>/etc</filename> have the highest priority, files in
  46     <filename>/run</filename> take precedence over files with the same
  47     name in <filename>/usr/lib</filename>. This can be used to
  48     override a system-supplied link file with a local file if needed.
  49     As a special case, an empty file (file size 0) or symlink with the
  50     same name pointing to <filename>/dev/null</filename> disables the
  51     configuration file entirely (it is "masked").</para>
  52
  53     <para>The link file contains a [Match] section, which determines if a given link file may be applied to a
  54     given device, as well as a [Link] section specifying how the device should be configured. The first (in
  55     lexical order) of the link files that matches a given device is applied. Note that a default file
  56     <filename>99-default.link</filename> is shipped by the system. Any user-supplied
  57     <filename>.link</filename> should hence have a lexically earlier name to be considered at all.</para>
  58
  59     <para>See <citerefentry><refentrytitle>udevadm</refentrytitle><manvolnum>8</manvolnum></citerefentry> for
  60     diagnosing problems with <filename>.link</filename> files.</para>
  61   </refsect1>
  62
  63   <refsect1>
  64     <title>[Match] Section Options</title>
  65
  66     <para>A link file is said to match a device if each of the entries in the [Match] section matches, or if
  67     the section is empty. The following keys are accepted:</para>
  68
  69     <variablelist class='network-directives'>
  70       <varlistentry>
  71         <term><varname>MACAddress=</varname></term>
  72         <listitem>
  73           <para>A whitespace-separated list of hardware addresses. Use full colon-, hyphen- or dot-delimited hexadecimal. See the example below.
  74           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
  75           of hardware addresses defined prior to this is reset.</para>
  76
  77           <para>Example:
  78           <programlisting>MACAddress=01:23:45:67:89:ab 00-11-22-33-44-55 AABB.CCDD.EEFF</programlisting></para>
  79         </listitem>
  80       </varlistentry>
  81       <varlistentry>
  82         <term><varname>OriginalName=</varname></term>
  83         <listitem>
  84           <para>A whitespace-separated list of shell-style globs matching
  85           the device name, as exposed by the udev property
  86           "INTERFACE". This cannot be used to match on names that have
  87           already been changed from userspace. Caution is advised when matching on
  88           kernel-assigned names, as they are known to be unstable
  89           between reboots.</para>
  90         </listitem>
  91       </varlistentry>
  92       <varlistentry>
  93         <term><varname>Path=</varname></term>
  94         <listitem>
  95           <para>A whitespace-separated list of shell-style globs matching
  96           the persistent path, as exposed by the udev property
  97           <varname>ID_PATH</varname>.</para>
  98         </listitem>
  99       </varlistentry>
 100       <varlistentry>
 101         <term><varname>Driver=</varname></term>
 102         <listitem>
 103           <para>A whitespace-separated list of shell-style globs matching the driver currently bound to the
 104           device, as exposed by the udev property <varname>DRIVER</varname> of its parent device, or if that
 105           is not set, the driver as exposed by <command>ethtool -i</command> of the device itself.</para>
 106         </listitem>
 107       </varlistentry>
 108       <varlistentry>
 109         <term><varname>Type=</varname></term>
 110         <listitem>
 111           <para>A whitespace-separated list of shell-style globs matching
 112           the device type, as exposed by the udev
 113           property <varname>DEVTYPE</varname>.</para>
 114         </listitem>
 115       </varlistentry>
 116       <varlistentry>
 117         <term><varname>Host=</varname></term>
 118         <listitem>
 119           <para>Matches against the hostname or machine
 120           ID of the host. See <varname>ConditionHost=</varname> in
 121           <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 122           for details.</para>
 123         </listitem>
 124       </varlistentry>
 125       <varlistentry>
 126         <term><varname>Virtualization=</varname></term>
 127         <listitem>
 128           <para>Checks whether the system is executed in
 129           a virtualized environment and optionally test
 130           whether it is a specific implementation. See
 131           <varname>ConditionVirtualization=</varname> in
 132           <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 133           for details.</para>
 134         </listitem>
 135       </varlistentry>
 136       <varlistentry>
 137         <term><varname>KernelCommandLine=</varname></term>
 138         <listitem>
 139           <para>Checks whether a specific kernel command line option
 140           is set (or if prefixed with the exclamation mark unset). See
 141           <varname>ConditionKernelCommandLine=</varname> in
 142           <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 143           for details.</para>
 144         </listitem>
 145       </varlistentry>
 146         <varlistentry>
 147           <term><varname>KernelVersion=</varname></term>
 148           <listitem>
 149             <para>Checks whether the kernel version (as reported by <command>uname -r</command>) matches a certain
 150             expression (or if prefixed with the exclamation mark does not match it). See
 151             <varname>ConditionKernelVersion=</varname> in
 152             <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry> for
 153             details.
 154             </para>
 155           </listitem>
 156         </varlistentry>
 157       <varlistentry>
 158         <term><varname>Architecture=</varname></term>
 159         <listitem>
 160           <para>Checks whether the system is running on a specific
 161           architecture. See <varname>ConditionArchitecture=</varname>
 162           in
 163           <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 164           for details.</para>
 165         </listitem>
 166       </varlistentry>
 167     </variablelist>
 168
 169   </refsect1>
 170
 171   <refsect1>
 172     <title>[Link] Section Options</title>
 173
 174     <para>The [Link] section accepts the following
 175     keys:</para>
 176
 177     <variablelist class='network-directives'>
 178       <varlistentry>
 179         <term><varname>Description=</varname></term>
 180         <listitem>
 181           <para>A description of the device.</para>
 182         </listitem>
 183       </varlistentry>
 184       <varlistentry>
 185         <term><varname>Alias=</varname></term>
 186         <listitem>
 187           <para>The <varname>ifalias</varname> interface property is set to this value.</para>
 188         </listitem>
 189       </varlistentry>
 190       <varlistentry>
 191         <term><varname>MACAddressPolicy=</varname></term>
 192         <listitem>
 193           <para>The policy by which the MAC address should be set. The
 194           available policies are:
 195           </para>
 196
 197           <variablelist>
 198             <varlistentry>
 199               <term><option>persistent</option></term>
 200               <listitem>
 201                 <para>If the hardware has a persistent MAC address, as
 202                 most hardware should, and if it is used by the kernel,
 203                 nothing is done. Otherwise, a new MAC address is
 204                 generated which is guaranteed to be the same on every
 205                 boot for the given machine and the given device, but
 206                 which is otherwise random. This feature depends on ID_NET_NAME_*
 207                 properties to exist for the link. On hardware where these
 208                 properties are not set, the generation of a persistent MAC address
 209                 will fail.</para>
 210               </listitem>
 211             </varlistentry>
 212             <varlistentry>
 213               <term><option>random</option></term>
 214               <listitem>
 215                 <para>If the kernel is using a random MAC address,
 216                 nothing is done. Otherwise, a new address is randomly
 217                 generated each time the device appears, typically at
 218                 boot. Either way, the random address will have the
 219                 <literal>unicast</literal> and
 220                 <literal>locally administered</literal> bits set.</para>
 221               </listitem>
 222             </varlistentry>
 223             <varlistentry>
 224               <term><option>none</option></term>
 225               <listitem>
 226                 <para>Keeps the MAC address assigned by the kernel.</para>
 227               </listitem>
 228             </varlistentry>
 229           </variablelist>
 230         </listitem>
 231       </varlistentry>
 232       <varlistentry>
 233         <term><varname>MACAddress=</varname></term>
 234         <listitem>
 235           <para>The MAC address to use, if no
 236           <varname>MACAddressPolicy=</varname>
 237           is specified.</para>
 238         </listitem>
 239       </varlistentry>
 240       <varlistentry>
 241         <term><varname>NamePolicy=</varname></term>
 242         <listitem>
 243           <para>An ordered, space-separated list of policies by which the interface name should be set.
 244           <varname>NamePolicy=</varname> may be disabled by specifying <option>net.ifnames=0</option> on the
 245           kernel command line.  Each of the policies may fail, and the first successful one is used. The name
 246           is not set directly, but is exported to udev as the property <option>ID_NET_NAME</option>, which
 247           is, by default, used by a udev rule to set <varname>NAME</varname>. The available policies are:
 248           </para>
 249
 250           <variablelist>
 251             <varlistentry>
 252               <term><option>kernel</option></term>
 253               <listitem>
 254                 <para>If the kernel claims that the name it has set
 255                 for a device is predictable, then no renaming is
 256                 performed.</para>
 257               </listitem>
 258             </varlistentry>
 259             <varlistentry>
 260               <term><option>database</option></term>
 261               <listitem>
 262                 <para>The name is set based on entries in the udev's
 263                 Hardware Database with the key
 264                 <varname>ID_NET_NAME_FROM_DATABASE</varname>.
 265                 </para>
 266               </listitem>
 267             </varlistentry>
 268             <varlistentry>
 269               <term><option>onboard</option></term>
 270               <listitem>
 271                 <para>The name is set based on information given by
 272                 the firmware for on-board devices, as exported by the
 273                 udev property <varname>ID_NET_NAME_ONBOARD</varname>.
 274                 </para>
 275               </listitem>
 276             </varlistentry>
 277             <varlistentry>
 278               <term><option>slot</option></term>
 279               <listitem>
 280                 <para>The name is set based on information given by
 281                 the firmware for hot-plug devices, as exported by the
 282                 udev property <varname>ID_NET_NAME_SLOT</varname>.
 283                 </para>
 284               </listitem>
 285             </varlistentry>
 286             <varlistentry>
 287               <term><option>path</option></term>
 288               <listitem>
 289                 <para>The name is set based on the device's physical
 290                 location, as exported by the udev property
 291                 <varname>ID_NET_NAME_PATH</varname>.</para>
 292               </listitem>
 293             </varlistentry>
 294             <varlistentry>
 295               <term><option>mac</option></term>
 296               <listitem>
 297                 <para>The name is set based on the device's persistent
 298                 MAC address, as exported by the udev property
 299                 <varname>ID_NET_NAME_MAC</varname>.</para>
 300               </listitem>
 301             </varlistentry>
 302             <varlistentry>
 303               <term><option>keep</option></term>
 304               <listitem>
 305                 <para>If the device already had a name given by userspace (as part of creation of the device
 306                 or a rename), keep it.</para>
 307               </listitem>
 308             </varlistentry>
 309           </variablelist>
 310         </listitem>
 311       </varlistentry>
 312       <varlistentry>
 313         <term><varname>Name=</varname></term>
 314         <listitem>
 315           <para>The interface name to use in case all the
 316           policies specified in
 317           <varname>NamePolicy=</varname> fail, or in case
 318           <varname>NamePolicy=</varname> is missing or
 319           disabled.</para>
 320
 321           <para>Note that specifying a name that the kernel might use for another
 322           interface (for example <literal>eth0</literal>) is dangerous because the
 323           name assignment done by udev will race with the assignment done by the
 324           kernel, and only one interface may use the name. Depending on the order of
 325           operations, either udev or the kernel will win, making the naming
 326           unpredictable. It is best to use some different prefix, for example
 327           <literal>internal0</literal>/<literal>external0</literal> or
 328           <literal>lan0</literal>/<literal>lan1</literal>/<literal>lan3</literal>.
 329           </para>
 330         </listitem>
 331       </varlistentry>
 332       <varlistentry>
 333         <term><varname>MTUBytes=</varname></term>
 334         <listitem>
 335           <para>The maximum transmission unit in bytes to set for the
 336           device. The usual suffixes K, M, G, are supported and are
 337           understood to the base of 1024.</para>
 338         </listitem>
 339       </varlistentry>
 340       <varlistentry>
 341         <term><varname>BitsPerSecond=</varname></term>
 342         <listitem>
 343           <para>The speed to set for the device, the value is rounded
 344           down to the nearest Mbps. The usual suffixes K, M, G, are
 345           supported and are understood to the base of 1000.</para>
 346         </listitem>
 347       </varlistentry>
 348       <varlistentry>
 349         <term><varname>Duplex=</varname></term>
 350         <listitem>
 351           <para>The duplex mode to set for the device. The accepted values are <option>half</option> and
 352           <option>full</option>.</para>
 353         </listitem>
 354       </varlistentry>
 355       <varlistentry>
 356         <term><varname>AutoNegotiation=</varname></term>
 357         <listitem>
 358           <para>Takes a boolean. If set to yes, automatic negotiation of transmission parameters is enabled.
 359           Autonegotiation is a procedure by which two connected ethernet devices choose
 360           common transmission parameters, such as speed, duplex mode, and flow control.
 361           When unset, the kernel's default will be used.</para>
 362
 363           <para>Note that if autonegotiation is enabled, speed and duplex settings are
 364           read-only. If autonegotation is disabled, speed and duplex settings are writable
 365           if the driver supports multiple link modes.</para>
 366         </listitem>
 367       </varlistentry>
 368       <varlistentry>
 369         <term><varname>WakeOnLan=</varname></term>
 370         <listitem>
 371           <para>The Wake-on-LAN policy to set for the device. The
 372           supported values are:</para>
 373
 374           <variablelist>
 375             <varlistentry>
 376               <term><option>phy</option></term>
 377               <listitem>
 378                 <para>Wake on PHY activity.</para>
 379               </listitem>
 380             </varlistentry>
 381             <varlistentry>
 382               <term><option>unicast</option></term>
 383               <listitem>
 384                 <para>Wake on unicast messages.</para>
 385               </listitem>
 386             </varlistentry>
 387             <varlistentry>
 388               <term><option>multicast</option></term>
 389               <listitem>
 390                 <para>Wake on multicast messages.</para>
 391               </listitem>
 392             </varlistentry>
 393             <varlistentry>
 394               <term><option>broadcast</option></term>
 395               <listitem>
 396                 <para>Wake on broadcast messages.</para>
 397               </listitem>
 398             </varlistentry>
 399             <varlistentry>
 400               <term><option>arp</option></term>
 401               <listitem>
 402                 <para>Wake on ARP.</para>
 403               </listitem>
 404             </varlistentry>
 405             <varlistentry>
 406               <term><option>magic</option></term>
 407               <listitem>
 408                 <para>Wake on receipt of a magic packet.
 409                 </para>
 410               </listitem>
 411             </varlistentry>
 412             <varlistentry>
 413               <term><option>secureon</option></term>
 414               <listitem>
 415                 <para>Enable secureon(tm) password for MagicPacket(tm).
 416                 </para>
 417               </listitem>
 418             </varlistentry>
 419             <varlistentry>
 420               <term><option>off</option></term>
 421               <listitem>
 422                 <para>Never wake.</para>
 423               </listitem>
 424             </varlistentry>
 425           </variablelist>
 426
 427           <para>Defaults to <option>off</option>.</para>
 428         </listitem>
 429       </varlistentry>
 430       <varlistentry>
 431         <term><varname>Port=</varname></term>
 432         <listitem>
 433           <para>The port option is used to select the device port. The
 434           supported values are:</para>
 435
 436           <variablelist>
 437             <varlistentry>
 438               <term><option>tp</option></term>
 439               <listitem>
 440                 <para>An Ethernet interface using Twisted-Pair cable as the medium.</para>
 441               </listitem>
 442             </varlistentry>
 443             <varlistentry>
 444               <term><option>aui</option></term>
 445               <listitem>
 446                 <para>Attachment Unit Interface (AUI). Normally used with hubs.
 447                 </para>
 448               </listitem>
 449             </varlistentry>
 450             <varlistentry>
 451               <term><option>bnc</option></term>
 452               <listitem>
 453                 <para>An Ethernet interface using BNC connectors and co-axial cable.</para>
 454               </listitem>
 455             </varlistentry>
 456             <varlistentry>
 457               <term><option>mii</option></term>
 458               <listitem>
 459                 <para>An Ethernet interface using a Media Independent Interface (MII).</para>
 460               </listitem>
 461             </varlistentry>
 462             <varlistentry>
 463               <term><option>fibre</option></term>
 464               <listitem>
 465                 <para>An Ethernet interface using Optical Fibre as the medium.</para>
 466               </listitem>
 467             </varlistentry>
 468           </variablelist>
 469         </listitem>
 470       </varlistentry>
 471       <varlistentry>
 472         <term><varname>Advertise=</varname></term>
 473         <listitem>
 474           <para>This sets what speeds and duplex modes of operation are advertised for auto-negotiation.
 475           This implies <literal>AutoNegotiation=yes</literal>. The supported values are:
 476
 477           <table>
 478             <title>Supported advertise values</title>
 479             <tgroup cols='3'>
 480               <colspec colname='Advertise' />
 481               <colspec colname='Speed' />
 482               <colspec colname='Duplex Mode' />
 483
 484               <thead><row>
 485                 <entry>Advertise</entry>
 486                 <entry>Speed (Mbps)</entry>
 487                 <entry>Duplex Mode</entry>
 488               </row></thead>
 489               <tbody>
 490                 <row><entry><option>10baset-half</option></entry>
 491                 <entry>10</entry><entry>half</entry></row>
 492
 493                 <row><entry><option>10baset-full</option></entry>
 494                 <entry>10</entry><entry>full</entry></row>
 495
 496                 <row><entry><option>100baset-half</option></entry>
 497                 <entry>100</entry><entry>half</entry></row>
 498
 499                 <row><entry><option>100baset-full</option></entry>
 500                 <entry>100</entry><entry>full</entry></row>
 501
 502                 <row><entry><option>1000baset-half</option></entry>
 503                 <entry>1000</entry><entry>half</entry></row>
 504
 505                 <row><entry><option>1000baset-full</option></entry>
 506                 <entry>1000</entry><entry>full</entry></row>
 507
 508                 <row><entry><option>10000baset-full</option></entry>
 509                 <entry>10000</entry><entry>full</entry></row>
 510
 511                 <row><entry><option>2500basex-full</option></entry>
 512                 <entry>2500</entry><entry>full</entry></row>
 513
 514                 <row><entry><option>1000basekx-full</option></entry>
 515                 <entry>1000</entry><entry>full</entry></row>
 516
 517                 <row><entry><option>10000basekx4-full</option></entry>
 518                 <entry>10000</entry><entry>full</entry></row>
 519
 520                 <row><entry><option>10000basekr-full</option></entry>
 521                 <entry>10000</entry><entry>full</entry></row>
 522
 523                 <row><entry><option>10000baser-fec</option></entry>
 524                 <entry>10000</entry><entry>full</entry></row>
 525
 526                 <row><entry><option>20000basemld2-full</option></entry>
 527                 <entry>20000</entry><entry>full</entry></row>
 528
 529                 <row><entry><option>20000basekr2-full</option></entry>
 530                 <entry>20000</entry><entry>full</entry></row>
 531               </tbody>
 532             </tgroup>
 533           </table>
 534
 535           By default this is unset, i.e. all possible modes will be advertised.
 536           This option may be specified more than once, in which case all specified speeds and modes are advertised.
 537           If the empty string is assigned to this option, the list is reset, and all prior assignments have no effect.
 538           </para>
 539         </listitem>
 540       </varlistentry>
 541       <varlistentry>
 542         <term><varname>TCPSegmentationOffload=</varname></term>
 543         <listitem>
 544           <para>Takes a boolean. If set to true, the TCP Segmentation Offload (TSO) is enabled.
 545           When unset, the kernel's default will be used.</para>
 546         </listitem>
 547       </varlistentry>
 548        <varlistentry>
 549       <term><varname>TCP6SegmentationOffload=</varname></term>
 550         <listitem>
 551           <para>Takes a boolean. If set to true, the TCP6 Segmentation Offload (tx-tcp6-segmentation) is enabled.
 552           When unset, the kernel's default will be used.</para>
 553         </listitem>
 554       </varlistentry>
 555       <varlistentry>
 556         <term><varname>GenericSegmentationOffload=</varname></term>
 557         <listitem>
 558           <para>Takes a boolean. If set to true, the Generic Segmentation Offload (GSO) is enabled.
 559           When unset, the kernel's default will be used.</para>
 560         </listitem>
 561       </varlistentry>
 562     <varlistentry>
 563         <term><varname>GenericReceiveOffload=</varname></term>
 564         <listitem>
 565           <para>Takes a boolean. If set to true, the Generic Receive Offload (GRO) is enabled.
 566           When unset, the kernel's default will be used.</para>
 567         </listitem>
 568       </varlistentry>
 569       <varlistentry>
 570         <term><varname>LargeReceiveOffload=</varname></term>
 571         <listitem>
 572           <para>Takes a boolean. If set to true, the Large Receive Offload (LRO) is enabled.
 573           When unset, the kernel's default will be used.</para>
 574         </listitem>
 575       </varlistentry>
 576       <varlistentry>
 577         <term><varname>RxChannels=</varname></term>
 578         <listitem>
 579           <para>Sets the number of receive channels (a number between 1 and 4294967295) .</para>
 580         </listitem>
 581       </varlistentry>
 582       <varlistentry>
 583         <term><varname>TxChannels=</varname></term>
 584         <listitem>
 585           <para>Sets the number of transmit channels (a number between 1 and 4294967295).</para>
 586         </listitem>
 587       </varlistentry>
 588       <varlistentry>
 589         <term><varname>OtherChannels=</varname></term>
 590         <listitem>
 591           <para>Sets the number of other channels (a number between 1 and 4294967295).</para>
 592         </listitem>
 593       </varlistentry>
 594       <varlistentry>
 595         <term><varname>CombinedChannels=</varname></term>
 596         <listitem>
 597           <para>Sets the number of combined set channels (a number between 1 and 4294967295).</para>
 598         </listitem>
 599       </varlistentry>
 600     </variablelist>
 601   </refsect1>
 602
 603   <refsect1>
 604     <title>Examples</title>
 605
 606     <example>
 607       <title>/usr/lib/systemd/network/99-default.link</title>
 608
 609       <para>The link file <filename>99-default.link</filename> that is
 610       shipped with systemd defines the default naming policy for
 611       links.</para>
 612
 613       <programlisting>[Link]
 614 NamePolicy=kernel database onboard slot path
 615 MACAddressPolicy=persistent</programlisting>
 616     </example>
 617
 618     <example>
 619       <title>/etc/systemd/network/10-dmz.link</title>
 620
 621       <para>This example assigns the fixed name
 622       <literal>dmz0</literal> to the interface with the MAC address
 623       00:a0:de:63:7a:e6:</para>
 624
 625       <programlisting>[Match]
 626 MACAddress=00:a0:de:63:7a:e6
 627
 628 [Link]
 629 Name=dmz0</programlisting>
 630     </example>
 631
 632     <example>
 633       <title>/etc/systemd/network/10-internet.link</title>
 634
 635       <para>This example assigns the fixed name
 636       <literal>internet0</literal> to the interface with the device
 637       path <literal>pci-0000:00:1a.0-*</literal>:</para>
 638
 639       <programlisting>[Match]
 640 Path=pci-0000:00:1a.0-*
 641
 642 [Link]
 643 Name=internet0</programlisting>
 644     </example>
 645
 646     <example>
 647       <title>/etc/systemd/network/25-wireless.link</title>
 648
 649       <para>Here's an overly complex example that shows the use of a large number of [Match] and [Link] settings.</para>
 650
 651       <programlisting>[Match]
 652 MACAddress=12:34:56:78:9a:bc
 653 Driver=brcmsmac
 654 Path=pci-0000:02:00.0-*
 655 Type=wlan
 656 Virtualization=no
 657 Host=my-laptop
 658 Architecture=x86-64
 659
 660 [Link]
 661 Name=wireless0
 662 MTUBytes=1450
 663 BitsPerSecond=10M
 664 WakeOnLan=magic
 665 MACAddress=cb:a9:87:65:43:21</programlisting>
 666     </example>
 667   </refsect1>
 668
 669   <refsect1>
 670     <title>See Also</title>
 671     <para>
 672       <citerefentry>
 673         <refentrytitle>systemd-udevd.service</refentrytitle><manvolnum>8</manvolnum>
 674       </citerefentry>,
 675       <citerefentry>
 676         <refentrytitle>udevadm</refentrytitle><manvolnum>8</manvolnum>
 677       </citerefentry>,
 678       <citerefentry>
 679         <refentrytitle>systemd.netdev</refentrytitle><manvolnum>5</manvolnum>
 680       </citerefentry>,
 681       <citerefentry>
 682         <refentrytitle>systemd.network</refentrytitle><manvolnum>5</manvolnum>
 683       </citerefentry>
 684     </para>
 685   </refsect1>
 686
 687 </refentry>