diff --git a/man/rules/meson.build b/man/rules/meson.build
index 6894158466..13feadc66f 100644
--- a/man/rules/meson.build
+++ b/man/rules/meson.build
@@ -824,6 +824,7 @@ manpages = [
['systemd.kill', '5', [], ''],
['systemd.link', '5', [], ''],
['systemd.mount', '5', [], ''],
+ ['systemd.net-naming-scheme', '7', [], ''],
['systemd.netdev', '5', [], 'ENABLE_NETWORKD'],
['systemd.network', '5', [], 'ENABLE_NETWORKD'],
['systemd.nspawn', '5', [], ''],
diff --git a/man/systemd-udevd.service.xml b/man/systemd-udevd.service.xml
index cf8087ccb3..c267bb2b11 100644
--- a/man/systemd-udevd.service.xml
+++ b/man/systemd-udevd.service.xml
@@ -171,15 +171,12 @@
net.naming-scheme=
Network interfaces are renamed to give them predictable names when possible (unless
- net.ifnames=0 is specified, see above). The names are derived from various
- device metadata fields. Newer versions of systemd-udevd.service take more of
- these fields into account, improving (and thus possibly changing) the names used for the same
- devices. With this kernel command line option it is possible to pick a specific version of this
- algorithm. It expects a naming scheme identifier as argument. Currently the following identifiers
- are known: v238, v239, v240 which each
- implement the naming scheme that was the default in the indicated systemd version. In addition,
- latest may be used to designate the latest scheme known (to this particular
- version of systemd-udevd.service).
+ net.ifnames=0 is specified, see above). With this kernel command line option it
+ is possible to pick a specific version of this algorithm and override the default chosen at
+ compilation time. Expects one of the naming scheme identifiers listed in
+ systemd.net-naming-scheme7,
+ or latest to select the latest scheme known (to this particular version of
+ systemd-udevd.service).
Note that selecting a specific scheme is not sufficient to fully stabilize interface naming:
the naming is generally derived from driver attributes exposed by the kernel. As the kernel is
@@ -188,9 +185,8 @@
-
-
+
+
See Also
diff --git a/man/systemd.link.xml b/man/systemd.link.xml
index ea744bd251..b1be32955e 100644
--- a/man/systemd.link.xml
+++ b/man/systemd.link.xml
@@ -278,6 +278,7 @@
The name is set based on information given by
the firmware for on-board devices, as exported by the
udev property ID_NET_NAME_ONBOARD.
+ See systemd.net-naming-scheme7.
@@ -287,6 +288,7 @@
The name is set based on information given by
the firmware for hot-plug devices, as exported by the
udev property ID_NET_NAME_SLOT.
+ See systemd.net-naming-scheme7.
@@ -295,7 +297,9 @@
The name is set based on the device's physical
location, as exported by the udev property
- ID_NET_NAME_PATH.
+ ID_NET_NAME_PATH.
+ See systemd.net-naming-scheme7.
+
@@ -303,7 +307,9 @@
The name is set based on the device's persistent
MAC address, as exported by the udev property
- ID_NET_NAME_MAC.
+ ID_NET_NAME_MAC.
+ See systemd.net-naming-scheme7.
+
diff --git a/man/systemd.net-naming-scheme.xml b/man/systemd.net-naming-scheme.xml
new file mode 100644
index 0000000000..f86ad8d63a
--- /dev/null
+++ b/man/systemd.net-naming-scheme.xml
@@ -0,0 +1,418 @@
+
+
+
+
+
+
+ systemd.net-naming-scheme
+ systemd
+
+
+
+ systemd.net-naming-scheme
+ 7
+
+
+
+ systemd.net-naming-scheme
+ Network device naming schemes
+
+
+
+ Description
+
+ Network interfaces may be renamed to give them predictable names when there's enough information to
+ generate appropriate names and the use of certain types of names is configured. This page describes the
+ first part, i.e. what possible names may be generated. Those names are generated by the
+ systemd-udevd.service8
+ builtin net_id and exported as udev properties
+ (ID_NET_NAME_ONBOARD=, ID_NET_LABEL_ONBOARD=,
+ ID_NET_NAME_PATH=, ID_NET_NAME_SLOT=).
+
+ Names are derived from various device metadata attributes. Newer versions of udev take more of
+ these attributes into account, improving (and thus possibly changing) the names used for the same
+ devices. Differents version of the naming rules are called "naming 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 using the net.naming-scheme= kernel
+ command line switch, see
+ systemd-udevd.service8.
+ Available naming schemes are described below.
+
+ After the udev proprties have been generated, appropriate udev rules may be used to actually rename
+ devices based on those properties. See the description of NamePolicy= in
+ systemd.link5.
+
+
+
+
+ Naming
+
+ All names start with a two-character prefix that signifies the interface type.
+
+
+ Two character prefixes based on the type of interface
+
+
+
+
+ Prefix
+ Description
+
+
+
+
+ en
+ Ethernet
+
+
+ ib
+ InfiniBand
+
+
+ sl
+ serial line IP (slip)
+
+
+ wl
+ Wireless local area network (WLAN)
+
+
+ ww
+ Wireless wide area network (WWAN)
+
+
+
+
+
+ The udev net_id builtin exports the following udev device properties:
+
+
+
+ ID_NET_NAME_ONBOARD=prefixonumber
+
+ This name is set based on the ordering information given by the firmware for
+ on-board devices. The name consists of the prefix, letter o, and a number
+ specified by the firmware. This is only available for PCI devices.
+
+
+
+
+ ID_NET_LABEL_ONBOARD=prefix label
+
+ 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.
+
+
+
+
+
+ ID_NET_NAME_MAC=prefixxAABBCCDDEEFF
+
+ This name consists of the prefix, letter x, and 12 hexadecimal
+ digits of the MAC address. It is available if the device has a fixed MAC address. Because this name
+ is based on an attribute of the card itself, it remains "stable" when the device is moved (even
+ between machines), but will change when the hardware is replaced.
+
+
+
+
+ ID_NET_NAME_SLOT=prefix[Pdomain]sslot[ffunction][nport_name|ddev_port]
+ ID_NET_NAME_SLOT=prefix[Pdomain]sslot[ffunction][nport_name|ddev_port]bnumber
+ ID_NET_NAME_SLOT=prefix[Pdomain]sslot[ffunction][nport_name|ddev_port]uport…[cconfig][iinterface]
+ ID_NET_NAME_SLOT=prefix[Pdomain]sslot[ffunction][nport_name|ddev_port]vslot
+
+ 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.
+
+
+ Slot naming schemes
+
+
+
+
+ Format
+ Description
+
+
+
+
+
+ prefix [Pdomain] sslot [ffunction] [nport_name | ddev_port]
+ PCI slot number
+
+
+
+ … bnumber
+ Broadcom bus (BCMA) core number
+
+
+
+ … uport… [cconfig] [iinterface]
+ USB port number chain
+
+
+
+ … vslot
+ SR-VIO slot number
+
+
+
+
+
+ The PCI domain is only prepended when it is not 0. All multi-function PCI devices will carry
+ the ffunction number in the device name, including
+ the function 0 device. For non-multi-function devices, the number is suppressed if 0. The port name
+ port_name is used, or the port number
+ ddev_port if the name is not known.
+
+ For BCMA devices, the core number is suppressed when 0.
+
+ 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.
+
+
+ SR-IOV virtual devices are named based on the name of the parent interface, with a suffix of
+ v and the virtual device number, with any leading zeros removed. The bus
+ number is ignored. This device type is found in IBM PowerVMs.
+
+
+
+ ID_NET_NAME_PATH=prefixcbus_id
+ ID_NET_NAME_PATH=prefixavendormodeliinstance
+ ID_NET_NAME_PATH=prefixiaddressnport_name
+ ID_NET_NAME_PATH=prefix[Pdomain]pbussslot[ffunction][nphys_port_name|ddev_port]
+ ID_NET_NAME_PATH=prefix[Pdomain]pbussslot[ffunction][nphys_port_name|ddev_port]bnumber
+ ID_NET_NAME_PATH=prefix[Pdomain]pbussslot[ffunction][nphys_port_name|ddev_port]uport…[cconfig][iinterface]
+
+ This property describes the device installation location. Different schemes are
+ used depending on the bus type, as described in the table below. For BCMA and USB devices, PCI path
+ information must known, and the full name consists of the prefix, PCI slot identifier, and USB or
+ BCMA location. The first two parts are denoted as "…" in the table below.
+
+
+ Path naming schemes
+
+
+
+
+ Format
+ Description
+
+
+
+
+
+ prefix cbus_id
+ CCW or grouped CCW device identifier
+
+
+
+ prefix avendor model iinstance
+ ACPI path names for ARM64 platform devices
+
+
+
+ prefix iaddress nport_name
+ Netdevsim (simulated networking device) device number and port name
+
+
+
+ prefix [Pdomain] pbus sslot [ffunction] [nphys_port_name | ddev_port]
+ PCI geographical location
+
+
+
+ … bnumber
+ Broadcom bus (BCMA) core number
+
+
+
+ … uport… [cconfig] [iinterface]
+ USB port number chain
+
+
+
+
+
+
+ CCW and grouped CCW devices are found in IBM System Z mainframes. Any leading zeros and
+ dots are suppressed.
+
+ For PCI, BCMA, and USB devices, the same rules as described above for slot naming are
+ used.
+
+
+
+
+
+
+ History
+
+ The following "naming schemes" have been defined:
+
+
+
+ v238
+
+ This is the naming naming that was implemented in systemd 238.
+
+
+
+ v239
+
+ Naming was changed for virtual network interfaces created with SR-IOV and NPAR and
+ for devices where the PCI network controller device does not have a slot number associated.
+
+ SR-IOV virtual devices are named based on the name of the parent interface, with a suffix of
+ vport, where port is the
+ virtual device number. Previously those virtual devices were named as if completely independent.
+
+
+ The ninth and later NPAR virtual devices are named following the scheme used for the first
+ eight NPAR partitions. Previously those devices were not renamed and the kernel default
+ ("ethN") was used.
+
+ Names are also generated for PCI devices where the PCI network controller device does not
+ have an associated slot number itself, but one of its parents does. Previously those devices were
+ not renamed and the kernel default was used.
+
+
+
+
+ v240
+
+ The ib prefix and stable names for infiniband devices are
+ introduced. Previously those devices were not renamed.
+
+ The ACPI index field (used in ID_NET_NAME_ONBOARD=) is now also used when
+ 0.
+
+ A new naming policy NamePolicy=keep was introduced. With this policy, if
+ the network device name was already set by userspace, the device will not be renamed
+ 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 keep is not
+ specified as the naming policy in the .link file. See
+ systemd.link5
+ for a description of NamePolicy=.
+
+
+
+ v243
+
+ Support for netdevsim (simulated networking devices) was added. Previously those devices were
+ not renamed.
+
+
+ Note that latest may be used to denote the latest scheme known (to this
+ particular version of systemd.
+
+
+
+
+ Examples
+
+
+ Using <command>udevadm test-builtin</command> to display device properties
+
+ $ udevadm test-builtin net_id /sys/class/net/enp0s31f6
+...
+Using default interface naming scheme 'v243'.
+ID_NET_NAMING_SCHEME=v243
+ID_NET_NAME_MAC=enx54ee75cb1dc0
+ID_OUI_FROM_DATABASE=Wistron InfoComm(Kunshan)Co.,Ltd.
+ID_NET_NAME_PATH=enp0s31f6
+...
+
+
+
+ PCI Ethernet card with firmware index "1"
+
+ ID_NET_NAME_ONBOARD=eno1
+ID_NET_NAME_ONBOARD_LABEL=enEthernet Port 1
+
+
+
+
+
+ PCI Ethernet card in hotplug slot with firmware index number
+
+ # /sys/devices/pci0000:00/0000:00:1c.3/0000:05:00.0/net/ens1
+ID_NET_NAME_MAC=enx000000000466
+ID_NET_NAME_PATH=enp5s0
+ID_NET_NAME_SLOT=ens1
+
+
+
+ PCI Ethernet multi-function card with 2 ports
+
+ # /sys/devices/pci0000:00/0000:00:1c.0/0000:02:00.0/net/enp2s0f0
+ID_NET_NAME_MAC=enx78e7d1ea46da
+ID_NET_NAME_PATH=enp2s0f0
+
+# /sys/devices/pci0000:00/0000:00:1c.0/0000:02:00.1/net/enp2s0f1
+ID_NET_NAME_MAC=enx78e7d1ea46dc
+ID_NET_NAME_PATH=enp2s0f1
+
+
+
+ PCI WLAN card
+
+ # /sys/devices/pci0000:00/0000:00:1c.1/0000:03:00.0/net/wlp3s0
+ID_NET_NAME_MAC=wlx0024d7e31130
+ID_NET_NAME_PATH=wlp3s0
+
+
+
+ PCI IB host adapter with 2 ports
+
+ # /sys/devices/pci0000:00/0000:00:03.0/0000:15:00.0/net/ibp21s0f0
+ID_NET_NAME_PATH=ibp21s0f0
+
+# /sys/devices/pci0000:00/0000:00:03.0/0000:15:00.1/net/ibp21s0f1
+ID_NET_NAME_PATH=ibp21s0f1
+
+
+
+ USB built-in 3G modem
+
+ # /sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.4/2-1.4:1.6/net/wwp0s29u1u4i6
+ID_NET_NAME_MAC=wwx028037ec0200
+ID_NET_NAME_PATH=wwp0s29u1u4i6
+
+
+
+ USB Android phone
+
+ # /sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2/2-1.2:1.0/net/enp0s29u1u2
+ID_NET_NAME_MAC=enxd626b3450fb5
+ID_NET_NAME_PATH=enp0s29u1u2
+
+
+
+ s390 grouped CCW interface
+
+ # /sys/devices/css0/0.0.0007/0.0.f5f0/group_device/net/encf5f0
+ID_NET_NAME_MAC=enx026d3c00000a
+ID_NET_NAME_PATH=encf5f0
+
+
+
+
+ See Also
+
+ udev7,
+ udevadm8,
+ the
+ original page describing stable interface names
+
+
+
+
diff --git a/src/udev/udev-builtin-net_id.c b/src/udev/udev-builtin-net_id.c
index 2c7dcf7d2a..4fcde34813 100644
--- a/src/udev/udev-builtin-net_id.c
+++ b/src/udev/udev-builtin-net_id.c
@@ -9,86 +9,7 @@
*
* http://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames
*
- * Two character prefixes based on the type of interface:
- * en — Ethernet
- * ib — InfiniBand
- * sl — serial line IP (slip)
- * wl — wlan
- * ww — wwan
- *
- * Type of names:
- * b — BCMA bus core number
- * c — bus id of a grouped CCW or CCW device,
- * with all leading zeros stripped [s390]
- * o[n|d]
- * — on-board device index number
- * s[f][n|d]
- * — hotplug slot index number
- * x — MAC address
- * [P]ps[f][n|d]
- * — PCI geographical location
- * [P]ps[f][u][..][c][i]
- * — USB port number chain
- * v - VIO slot number (IBM PowerVM)
- * ai — Platform bus ACPI instance id
- * in — Netdevsim bus address and port name
- *
- * All multi-function PCI devices will carry the [f] number in the
- * device name, including the function 0 device.
- *
- * SR-IOV virtual devices are named based on the name of the parent interface,
- * with a suffix of "v", where is the virtual device number.
- *
- * When using PCI geography, The PCI domain is only prepended when it is not 0.
- *
- * 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 == 1 and interface == 0 values are suppressed.
- *
- * PCI Ethernet card with firmware index "1":
- * ID_NET_NAME_ONBOARD=eno1
- * ID_NET_NAME_ONBOARD_LABEL=Ethernet Port 1
- *
- * PCI Ethernet card in hotplug slot with firmware index number:
- * /sys/devices/pci0000:00/0000:00:1c.3/0000:05:00.0/net/ens1
- * ID_NET_NAME_MAC=enx000000000466
- * ID_NET_NAME_PATH=enp5s0
- * ID_NET_NAME_SLOT=ens1
- *
- * PCI Ethernet multi-function card with 2 ports:
- * /sys/devices/pci0000:00/0000:00:1c.0/0000:02:00.0/net/enp2s0f0
- * ID_NET_NAME_MAC=enx78e7d1ea46da
- * ID_NET_NAME_PATH=enp2s0f0
- * /sys/devices/pci0000:00/0000:00:1c.0/0000:02:00.1/net/enp2s0f1
- * ID_NET_NAME_MAC=enx78e7d1ea46dc
- * ID_NET_NAME_PATH=enp2s0f1
- *
- * PCI wlan card:
- * /sys/devices/pci0000:00/0000:00:1c.1/0000:03:00.0/net/wlp3s0
- * ID_NET_NAME_MAC=wlx0024d7e31130
- * ID_NET_NAME_PATH=wlp3s0
- *
- * PCI IB host adapter with 2 ports:
- * /sys/devices/pci0000:00/0000:00:03.0/0000:15:00.0/net/ibp21s0f0
- * ID_NET_NAME_PATH=ibp21s0f0
- * /sys/devices/pci0000:00/0000:00:03.0/0000:15:00.1/net/ibp21s0f1
- * ID_NET_NAME_PATH=ibp21s0f1
- *
- * USB built-in 3G modem:
- * /sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.4/2-1.4:1.6/net/wwp0s29u1u4i6
- * ID_NET_NAME_MAC=wwx028037ec0200
- * ID_NET_NAME_PATH=wwp0s29u1u4i6
- *
- * USB Android phone:
- * /sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2/2-1.2:1.0/net/enp0s29u1u2
- * ID_NET_NAME_MAC=enxd626b3450fb5
- * ID_NET_NAME_PATH=enp0s29u1u2
- *
- * s390 grouped CCW interface:
- * /sys/devices/css0/0.0.0007/0.0.f5f0/group_device/net/encf5f0
- * ID_NET_NAME_MAC=enx026d3c00000a
- * ID_NET_NAME_PATH=encf5f0
+ * When the code here is changed, man/systemd.net-naming-scheme.xml must be updated too.
*/
#include