man/systemd.net-naming-scheme.xml

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   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
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   5
   6 <refentry id="systemd.net-naming-scheme">
   7   <refentryinfo>
   8     <title>systemd.net-naming-scheme</title>
   9     <productname>systemd</productname>
  10   </refentryinfo>
  11
  12   <refmeta>
  13     <refentrytitle>systemd.net-naming-scheme</refentrytitle>
  14     <manvolnum>7</manvolnum>
  15   </refmeta>
  16
  17   <refnamediv>
  18     <refname>systemd.net-naming-scheme</refname>
  19     <refpurpose>Network device naming schemes</refpurpose>
  20   </refnamediv>
  21
  22   <refsect1>
  23     <title>Description</title>
  24
  25     <para>Network interfaces names and MAC addresses may be generated based on certain stable interface
  26     attributes. This is possible when there is enough information about the device to generate those
  27     attributes and the use of this information is configured. This page describes interface naming, i.e. what
  28     possible names may be generated. Those names are generated by the
  29     <citerefentry><refentrytitle>systemd-udevd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
  30     builtin <command>net_id</command> and exported as udev properties
  31     (<varname>ID_NET_NAME_ONBOARD=</varname>, <varname>ID_NET_LABEL_ONBOARD=</varname>,
  32     <varname>ID_NET_NAME_PATH=</varname>, <varname>ID_NET_NAME_SLOT=</varname>).</para>
  33
  34     <para>Names and MAC addresses are derived from various stable device metadata attributes. Newer versions
  35     of udev take more of these attributes into account, improving (and thus possibly changing) the names and
  36     addresses used for the same devices. Different versions of those generation rules are called "naming
  37     schemes". The default naming scheme is chosen at compilation time. Usually this will be the latest
  38     implemented version, but it is also possible to set one of the older versions to preserve
  39     compatibility. This may be useful for example for distributions, which may introduce new versions of
  40     systemd in stable releases without changing the naming scheme. The naming scheme may also be overridden
  41     using the <varname>net.naming-scheme=</varname> kernel command line switch, see
  42     <citerefentry><refentrytitle>systemd-udevd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
  43     Available naming schemes are described below.</para>
  44
  45     <para>After the udev properties have been generated, appropriate udev rules may be used to actually rename
  46     devices based on those properties. See the description of <varname>NamePolicy=</varname> and
  47     <varname>MACAddressPolicy=</varname> in
  48     <citerefentry><refentrytitle>systemd.link</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
  49
  50     <para>Note that while the concept of network interface naming schemes is primarily relevant in the
  51     context of <filename>systemd-udevd.service</filename>, the
  52     <citerefentry><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry>
  53     container manager also takes it into account when naming network interfaces, see below.</para>
  54   </refsect1>
  55
  56   <refsect1>
  57     <title>Naming</title>
  58
  59     <para>All names start with a two-character prefix that signifies the interface type.</para>
  60
  61     <table>
  62       <title>Two character prefixes based on the type of interface</title>
  63
  64       <tgroup cols='2'>
  65         <thead>
  66           <row>
  67             <entry>Prefix</entry>
  68             <entry>Description</entry>
  69           </row>
  70         </thead>
  71         <tbody>
  72           <row>
  73             <entry><constant>en</constant></entry>
  74             <entry>Ethernet</entry>
  75           </row>
  76           <row>
  77             <entry><constant>ib</constant></entry>
  78             <entry>InfiniBand</entry>
  79           </row>
  80           <row>
  81             <entry><constant>sl</constant></entry>
  82             <entry>serial line IP (slip)</entry>
  83           </row>
  84           <row>
  85             <entry><constant>wl</constant></entry>
  86             <entry>Wireless local area network (WLAN)</entry>
  87           </row>
  88           <row>
  89             <entry><constant>ww</constant></entry>
  90             <entry>Wireless wide area network (WWAN)</entry>
  91           </row>
  92         </tbody>
  93       </tgroup>
  94     </table>
  95
  96     <para>The udev <command>net_id</command> builtin exports the following udev device properties:</para>
  97
  98     <variablelist>
  99         <varlistentry>
 100           <term><varname>ID_NET_NAME_ONBOARD=<replaceable>prefix</replaceable><constant>o</constant><replaceable>number</replaceable></varname></term>
 101
 102           <listitem><para>This name is set based on the ordering information given by the firmware for
 103           on-board devices. The name consists of the prefix, letter <constant>o</constant>, and a number
 104           specified by the firmware. This is only available for PCI devices.</para>
 105           </listitem>
 106         </varlistentry>
 107
 108         <varlistentry>
 109           <term><varname>ID_NET_LABEL_ONBOARD=<replaceable>prefix</replaceable> <replaceable>label</replaceable></varname></term>
 110
 111           <listitem><para>This property is set based on label given by the firmware for on-board devices. The
 112           name consists of the prefix concatenated with the label. This is only available for PCI devices.
 113           </para>
 114           </listitem>
 115         </varlistentry>
 116
 117         <varlistentry>
 118           <term><varname>ID_NET_NAME_MAC=<replaceable>prefix</replaceable><constant>x</constant><replaceable>AABBCCDDEEFF</replaceable></varname></term>
 119
 120           <listitem><para>This name consists of the prefix, letter <constant>x</constant>, and 12 hexadecimal
 121           digits of the MAC address. It is available if the device has a fixed MAC address. Because this name
 122           is based on an attribute of the card itself, it remains "stable" when the device is moved (even
 123           between machines), but will change when the hardware is replaced.</para>
 124           </listitem>
 125         </varlistentry>
 126
 127         <varlistentry>
 128           <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>
 129           <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>
 130           <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>
 131           <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>
 132
 133           <listitem><para>This property describes the slot position. Different schemes are used depending on
 134           the bus type, as described in the table below. In all cases, PCI slot information must be known. In
 135           case of USB, BCMA, and SR-VIO devices, the full name consists of the prefix, PCI slot identifier,
 136           and USB or BCMA or SR-VIO slot identifier. The first two parts are denoted as "…" in the table
 137           below.</para>
 138
 139           <table>
 140             <title>Slot naming schemes</title>
 141
 142             <tgroup cols='2'>
 143               <thead>
 144                 <row>
 145                   <entry>Format</entry>
 146                   <entry>Description</entry>
 147                 </row>
 148               </thead>
 149
 150               <tbody>
 151                 <row>
 152                   <entry><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>]</entry>
 153                   <entry>PCI slot number</entry>
 154                 </row>
 155
 156                 <row>
 157                   <entry>… <constant>b</constant><replaceable>number</replaceable></entry>
 158                   <entry>Broadcom bus (BCMA) core number</entry>
 159                 </row>
 160
 161                 <row>
 162                   <entry>… <constant>u</constant><replaceable>port</replaceable>… [<constant>c</constant><replaceable>config</replaceable>] [<constant>i</constant><replaceable>interface</replaceable>]</entry>
 163                   <entry>USB port number chain</entry>
 164                 </row>
 165
 166                 <row>
 167                   <entry>… <constant>v</constant><replaceable>slot</replaceable></entry>
 168                   <entry>SR-VIO slot number</entry>
 169                 </row>
 170               </tbody>
 171             </tgroup>
 172           </table>
 173
 174           <para>The PCI domain is only prepended when it is not 0. All multi-function PCI devices will carry
 175           the <constant>f<replaceable>function</replaceable></constant> number in the device name, including
 176           the function 0 device. For non-multi-function devices, the number is suppressed if 0. The port name
 177           <replaceable>port_name</replaceable> is used, or the port number
 178           <constant>d</constant><replaceable>dev_port</replaceable> if the name is not known.</para>
 179
 180           <para>For BCMA devices, the core number is suppressed when 0.</para>
 181
 182           <para>For USB devices the full chain of port numbers of hubs is composed. If the name gets longer
 183           than the maximum number of 15 characters, the name is not exported. The usual USB configuration
 184           number 1 and interface number 0 values are suppressed.</para>
 185           </listitem>
 186
 187           <para>SR-IOV virtual devices are named based on the name of the parent interface, with a suffix of
 188           <constant>v</constant> and the virtual device number, with any leading zeros removed. The bus
 189           number is ignored. This device type is found in IBM PowerVMs.</para>
 190         </varlistentry>
 191
 192         <varlistentry>
 193           <term><varname>ID_NET_NAME_PATH=<replaceable>prefix</replaceable><constant>c</constant><replaceable>bus_id</replaceable></varname></term>
 194           <term><varname>ID_NET_NAME_PATH=<replaceable>prefix</replaceable><constant>a</constant><replaceable>vendor</replaceable><replaceable>model</replaceable><constant>i</constant><replaceable>instance</replaceable></varname></term>
 195           <term><varname>ID_NET_NAME_PATH=<replaceable>prefix</replaceable><constant>i</constant><replaceable>address</replaceable><constant>n</constant><replaceable>port_name</replaceable></varname></term>
 196           <term><varname>ID_NET_NAME_PATH=<replaceable>prefix</replaceable>[<constant>P</constant><replaceable>domain</replaceable>]<constant>p</constant><replaceable>bus</replaceable><constant>s</constant><replaceable>slot</replaceable>[<constant>f</constant><replaceable>function</replaceable>][<constant>n</constant><replaceable>phys_port_name</replaceable>|<constant>d</constant><replaceable>dev_port</replaceable>]</varname></term>
 197           <term><varname>ID_NET_NAME_PATH=<replaceable>prefix</replaceable>[<constant>P</constant><replaceable>domain</replaceable>]<constant>p</constant><replaceable>bus</replaceable><constant>s</constant><replaceable>slot</replaceable>[<constant>f</constant><replaceable>function</replaceable>][<constant>n</constant><replaceable>phys_port_name</replaceable>|<constant>d</constant><replaceable>dev_port</replaceable>]<constant>b</constant><replaceable>number</replaceable></varname></term>
 198           <term><varname>ID_NET_NAME_PATH=<replaceable>prefix</replaceable>[<constant>P</constant><replaceable>domain</replaceable>]<constant>p</constant><replaceable>bus</replaceable><constant>s</constant><replaceable>slot</replaceable>[<constant>f</constant><replaceable>function</replaceable>][<constant>n</constant><replaceable>phys_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>
 199
 200           <listitem><para>This property describes the device installation location. Different schemes are
 201           used depending on the bus type, as described in the table below. For BCMA and USB devices, PCI path
 202           information must known, and the full name consists of the prefix, PCI slot identifier, and USB or
 203           BCMA location. The first two parts are denoted as "…" in the table below.</para>
 204
 205           <table>
 206             <title>Path naming schemes</title>
 207
 208             <tgroup cols='2'>
 209               <thead>
 210                 <row>
 211                   <entry>Format</entry>
 212                   <entry>Description</entry>
 213                 </row>
 214               </thead>
 215
 216               <tbody>
 217                 <row>
 218                   <entry><replaceable>prefix</replaceable> <constant>c</constant><replaceable>bus_id</replaceable></entry>
 219                   <entry>CCW or grouped CCW device identifier</entry>
 220                 </row>
 221
 222                 <row>
 223                   <entry><replaceable>prefix</replaceable> <constant>a</constant><replaceable>vendor</replaceable> <replaceable>model</replaceable> <constant>i</constant><replaceable>instance</replaceable></entry>
 224                   <entry>ACPI path names for ARM64 platform devices</entry>
 225                 </row>
 226
 227                 <row>
 228                   <entry><replaceable>prefix</replaceable> <constant>i</constant><replaceable>address</replaceable> <constant>n</constant><replaceable>port_name</replaceable></entry>
 229                   <entry>Netdevsim (simulated networking device) device number and port name</entry>
 230                 </row>
 231
 232                 <row>
 233                   <entry><replaceable>prefix</replaceable> [<constant>P</constant><replaceable>domain</replaceable>] <constant>p</constant><replaceable>bus</replaceable> <constant>s</constant><replaceable>slot</replaceable> [<constant>f</constant><replaceable>function</replaceable>] [<constant>n</constant><replaceable>phys_port_name</replaceable> | <constant>d</constant><replaceable>dev_port</replaceable>]</entry>
 234                   <entry>PCI geographical location</entry>
 235                 </row>
 236
 237                 <row>
 238                   <entry>… <constant>b</constant><replaceable>number</replaceable></entry>
 239                   <entry>Broadcom bus (BCMA) core number</entry>
 240                 </row>
 241
 242                 <row>
 243                   <entry>… <constant>u</constant><replaceable>port</replaceable>… [<constant>c</constant><replaceable>config</replaceable>] [<constant>i</constant><replaceable>interface</replaceable>]</entry>
 244                   <entry>USB port number chain</entry>
 245                 </row>
 246
 247               </tbody>
 248             </tgroup>
 249           </table>
 250
 251           <para>CCW and grouped CCW devices are found in IBM System Z mainframes. Any leading zeros and
 252           dots are suppressed.</para>
 253
 254           <para>For PCI, BCMA, and USB devices, the same rules as described above for slot naming are
 255           used.</para>
 256           </listitem>
 257         </varlistentry>
 258     </variablelist>
 259   </refsect1>
 260
 261   <refsect1>
 262     <title>History</title>
 263
 264     <para>The following "naming schemes" have been defined:</para>
 265
 266     <variablelist>
 267         <varlistentry>
 268           <term><constant>v238</constant></term>
 269
 270           <listitem><para>This is the naming scheme that was implemented in systemd 238.</para></listitem>
 271         </varlistentry>
 272
 273         <varlistentry>
 274           <term><constant>v239</constant></term>
 275
 276           <listitem><para>Naming was changed for virtual network interfaces created with SR-IOV and NPAR and
 277           for devices where the PCI network controller device does not have a slot number associated.</para>
 278
 279           <para>SR-IOV virtual devices are named based on the name of the parent interface, with a suffix of
 280           <literal>v<replaceable>port</replaceable></literal>, where <replaceable>port</replaceable> is the
 281           virtual device number. Previously those virtual devices were named as if completely independent.
 282           </para>
 283
 284           <para>The ninth and later NPAR virtual devices are named following the scheme used for the first
 285           eight NPAR partitions. Previously those devices were not renamed and the kernel default
 286           ("eth<replaceable>N</replaceable>") was used.</para>
 287
 288           <para>Names are also generated for PCI devices where the PCI network controller device does not
 289           have an associated slot number itself, but one of its parents does. Previously those devices were
 290           not renamed and the kernel default was used.</para>
 291           </listitem>
 292         </varlistentry>
 293
 294         <varlistentry>
 295           <term><constant>v240</constant></term>
 296
 297           <listitem><para>The <literal>ib</literal> prefix and stable names for infiniband devices are
 298           introduced. Previously those devices were not renamed.</para>
 299
 300           <para>The ACPI index field (used in <varname>ID_NET_NAME_ONBOARD=</varname>) is now also used when
 301           0.</para>
 302
 303           <para>A new naming policy <varname>NamePolicy=keep</varname> was introduced. With this policy, if
 304           the network device name was already set by userspace, the device will not be renamed
 305           again. Previously, this naming policy applied implicitly, and now it must be explicitly
 306           requested. Effectively, this means that network devices will be renamed according to the
 307           configuration, even if they have been renamed already, if <constant>keep</constant> is not
 308           specified as the naming policy in the <filename index="false">.link</filename> file. See
 309           <citerefentry><refentrytitle>systemd.link</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 310           for a description of <varname>NamePolicy=</varname>.</para></listitem>
 311         </varlistentry>
 312
 313         <varlistentry>
 314           <term><constant>v241</constant></term>
 315
 316           <listitem><para><option>MACAddressPolicy=persistent</option> was extended to set MAC addresses
 317           based on the device name. Previously addresses were only based on the
 318           <varname index="false">ID_NET_NAME_*</varname> attributes, which meant that interface names would
 319           never be generated for virtual devices. Now a persistent address will be generated for most
 320           devices, including in particular bridges.</para>
 321
 322           <para>Note: when userspace does not set a MAC address for a bridge device, the kernel will
 323           initially assign a random address, and then change it when the first device is enslaved to the
 324           bridge. With this naming policy change, bridges get a persistent MAC address based on the bridge
 325           name instead of the first enslaved device.</para></listitem>
 326         </varlistentry>
 327
 328         <varlistentry>
 329           <term><constant>v243</constant></term>
 330
 331           <listitem><para>Support for renaming netdevsim (simulated networking) devices was added. Previously
 332           those devices were not renamed.</para>
 333
 334           <para>Previously two-letter interface type prefix was prepended to
 335           <varname>ID_NET_LABEL_ONBOARD=</varname>. This is not done anymore.</para></listitem>
 336         </varlistentry>
 337
 338         <varlistentry>
 339           <term><constant>v245</constant></term>
 340
 341           <listitem><para>When
 342           <citerefentry><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 343           derives the name for the host side of the network interface created with
 344           <option>--network-veth</option> from the container name it previously simply truncated the result
 345           at 15 characters if longer (since that's the maximum length for network interface names). From now
 346           on, for any interface name that would be longer than 15 characters the last 4 characters are set to
 347           a 24bit hash value of the full interface name. This way network interface name collisions between
 348           multiple similarly named containers (who only differ in container name suffix) should be less
 349           likely (but still possible, since the 24bit hash value is very small).</para></listitem>
 350         </varlistentry>
 351       </variablelist>
 352
 353     <para>Note that <constant>latest</constant> may be used to denote the latest scheme known (to this
 354     particular version of systemd.</para>
 355   </refsect1>
 356
 357   <refsect1>
 358     <title>Examples</title>
 359
 360     <example>
 361       <title>Using <command>udevadm test-builtin</command> to display device properties</title>
 362
 363       <programlisting>$ udevadm test-builtin net_id /sys/class/net/enp0s31f6
 364 ...
 365 Using default interface naming scheme 'v243'.
 366 ID_NET_NAMING_SCHEME=v243
 367 ID_NET_NAME_MAC=enx54ee75cb1dc0
 368 ID_OUI_FROM_DATABASE=Wistron InfoComm(Kunshan)Co.,Ltd.
 369 ID_NET_NAME_PATH=enp0s31f6
 370 ...</programlisting>
 371     </example>
 372
 373     <example>
 374       <title>PCI Ethernet card with firmware index "1"</title>
 375
 376       <programlisting>ID_NET_NAME_ONBOARD=eno1
 377 ID_NET_NAME_ONBOARD_LABEL=Ethernet Port 1
 378       </programlisting>
 379     </example>
 380
 381     <example>
 382       <title>PCI Ethernet card in hotplug slot with firmware index number</title>
 383
 384       <programlisting># /sys/devices/pci0000:00/0000:00:1c.3/0000:05:00.0/net/ens1
 385 ID_NET_NAME_MAC=enx000000000466
 386 ID_NET_NAME_PATH=enp5s0
 387 ID_NET_NAME_SLOT=ens1</programlisting>
 388     </example>
 389
 390     <example>
 391       <title>PCI Ethernet multi-function card with 2 ports</title>
 392
 393       <programlisting># /sys/devices/pci0000:00/0000:00:1c.0/0000:02:00.0/net/enp2s0f0
 394 ID_NET_NAME_MAC=enx78e7d1ea46da
 395 ID_NET_NAME_PATH=enp2s0f0
 396
 397 # /sys/devices/pci0000:00/0000:00:1c.0/0000:02:00.1/net/enp2s0f1
 398 ID_NET_NAME_MAC=enx78e7d1ea46dc
 399 ID_NET_NAME_PATH=enp2s0f1</programlisting>
 400     </example>
 401
 402     <example>
 403       <title>PCI WLAN card</title>
 404
 405       <programlisting># /sys/devices/pci0000:00/0000:00:1c.1/0000:03:00.0/net/wlp3s0
 406 ID_NET_NAME_MAC=wlx0024d7e31130
 407 ID_NET_NAME_PATH=wlp3s0</programlisting>
 408     </example>
 409
 410     <example>
 411       <title>PCI IB host adapter with 2 ports</title>
 412
 413       <programlisting># /sys/devices/pci0000:00/0000:00:03.0/0000:15:00.0/net/ibp21s0f0
 414 ID_NET_NAME_PATH=ibp21s0f0
 415
 416 # /sys/devices/pci0000:00/0000:00:03.0/0000:15:00.1/net/ibp21s0f1
 417 ID_NET_NAME_PATH=ibp21s0f1</programlisting>
 418     </example>
 419
 420     <example>
 421       <title>USB built-in 3G modem</title>
 422
 423       <programlisting># /sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.4/2-1.4:1.6/net/wwp0s29u1u4i6
 424 ID_NET_NAME_MAC=wwx028037ec0200
 425 ID_NET_NAME_PATH=wwp0s29u1u4i6</programlisting>
 426     </example>
 427
 428     <example>
 429       <title>USB Android phone</title>
 430
 431       <programlisting># /sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2/2-1.2:1.0/net/enp0s29u1u2
 432 ID_NET_NAME_MAC=enxd626b3450fb5
 433 ID_NET_NAME_PATH=enp0s29u1u2</programlisting>
 434     </example>
 435
 436     <example>
 437       <title>s390 grouped CCW interface</title>
 438
 439       <programlisting># /sys/devices/css0/0.0.0007/0.0.f5f0/group_device/net/encf5f0
 440 ID_NET_NAME_MAC=enx026d3c00000a
 441 ID_NET_NAME_PATH=encf5f0</programlisting>
 442     </example>
 443   </refsect1>
 444
 445   <refsect1>
 446     <title>See Also</title>
 447     <para>
 448       <citerefentry><refentrytitle>udev</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
 449       <citerefentry><refentrytitle>udevadm</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 450       <ulink url="https://systemd.io/PREDICTABLE_INTERFACE_NAMES">Predictable Network Interface Names</ulink>,
 451       <citerefentry><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 452     </para>
 453   </refsect1>
 454
 455 </refentry>