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RedHat 9 網路裝置命名規則

Scheme Description Example


Device names incorporate firmware or BIOS-provided index numbers for onboard devices. If this information is not available or applicable, udev uses scheme 2.



Device names incorporate firmware or BIOS-provided PCI Express (PCIe) hot plug slot index numbers. If this information is not available or applicable, udev uses scheme 3.



Device names incorporate the physical location of the connector of the hardware. If this information is not available or applicable, udev uses scheme 5.



Device names incorporate the MAC address. Red Hat Enterprise Linux does not use this scheme by default, but administrators can optionally use it.



The traditional unpredictable kernel naming scheme. If udev cannot apply any of the other schemes, the device manager uses this scheme.


By default, Red Hat Enterprise Linux selects the device name based on the NamePolicy setting in the /usr/lib/systemd/network/ file. The order of the values in NamePolicy is important. Red Hat Enterprise Linux uses the first device name that is both specified in the file and that udev generated.

If you manually configured udev rules to change the name of kernel devices, those rules take precedence.

Predictable network interface device names on the x86_64 platform explained

The interface name starts with a two-character prefix based on the type of interface:

  • en for Ethernet
  • wl for wireless LAN (WLAN)
  • ww for wireless wide area network (WWAN)

Additionally, one of the following is appended to one of the above-mentioned prefix based on the schema the udev device manager applies:

  • o<on-board_index_number>
  • s<hot_plug_slot_index_number>[f<function>][d<device_id>]

    Note that all multi-function PCI devices have the [f<function>] number in the device name, including the function 0 device.

  • x<MAC_address>
  • [P<domain_number>]p<bus>s<slot>[f<function>][d<device_id>]

    The [P<domain_number>] part defines the PCI geographical location. This part is only set if the domain number is not 0.

  • [P<domain_number>]p<bus>s<slot>[f<function>][u<usb_port>][…​][c<config>][i<interface>]

    For USB devices, the full chain of port numbers of hubs is composed. If the name is longer than the maximum (15 characters), the name is not exported. If there are multiple USB devices in the chain, udev suppresses the default values for USB configuration descriptors (c1) and USB interface descriptors (i0).

停用網路裝置連續名稱規則(Not Recommend)

Red Hat recommends not to disable consistent device naming and does not support this feature on hosts with more than one network interface. Disabling consistent device naming can cause different kind of problems. For example, if you add another network interface card to the system, the assignment of the kernel device names, such as eth0, is no longer fixed. Consequently, after a reboot, the Kernel can name the device differently.