Consistent Network Device Naming

Consistent Network Device Naming is a convention for naming Ethernet adapters in Linux.

It was created around 2009 to replace the old ethX naming scheme that caused problems on multihomed machines because the network interface controllers (NICs) would be named based on the order in which they were found by the kernel as it booted. Removing existing or adding new interfaces could cause the previously added ones to change names.[1] An Engineering Change Request was submitted to the PCI SIG firmware group on how system firmware can provide device naming to operating systems via the ACPI interface.[2]

Adoption

The convention was implemented for Dell in a module called biosdevname.[3]

Among the first major Linux distributions to adopt the module were Fedora 15 in May 2011[4][5] and Red Hat Enterprise Linux version 6.1.[6][7] It was also released in SUSE Linux Enterprise Server 11 Service Pack 2 in February 2012.[7] The newer Dell PowerEdge and Dell Precision models support the new names.[7]

An open-source implementation is available, based on the udev mechanism.[8][9] Red Hat Enterprise Linux 7 started using systemd for networking.[10]

Device naming rules

  • Onboard interfaces at firmware index numbers eno[1-N]
  • Interfaces at PCI Express hotplug slot numbers ens[1-N]
  • Adapters in the specified PCI slot, with slot index number on the adapter enp<PCI slot>s<card index no>
  • If firmware information is invalid or rules are disabled, use traditional eth[0-N][11]

References

  1. ^ Matt Domsch (October 9, 2009). "Network Device Naming mechanism and policy". LWN. Eklektix, Inc. Retrieved May 27, 2013.
  2. ^ "Archived copy" (PDF). Archived from the original (PDF) on 2017-01-06. Retrieved 2017-02-22.{{cite web}}: CS1 maint: archived copy as title (link)
  3. ^ "Fedora 15 Changing The Network Device Naming Scheme". Digitizer Linux News. January 25, 2011. Retrieved May 27, 2013.
  4. ^ Sean Michael Kerner (May 20, 2011). "Fedora 15 boosts Linux security". eSecurity Planet. Archived from the original on January 22, 2013. Retrieved May 27, 2013.
  5. ^ Joe Brockmeier (January 24, 2011). "Breaking a few eggs: Fedora 15 changes network device naming. Fedora 15 pioneering consistent network device naming". Network World.
  6. ^ "Appendix A. Consistent Network Device Naming". Red Hat Enterprise Linux 6 documentation. Retrieved May 27, 2013.
  7. ^ a b c Narendra K (July 2012). "Consistent Network Device Naming in Linux" (PDF). Dell Linux Engineering division. Retrieved May 27, 2013.
  8. ^ "Biosdevname - Consistent Network Device Naming". Retrieved May 27, 2013.
  9. ^ Matt Domsch and Jordan Hargrave. "Consistent Network Device Naming". Project web site. Fedora. Retrieved May 27, 2013.
  10. ^ "Understanding network persistent device naming in Red Hat Enterprise Linux 7". Archived from the original on 2017-03-28. Retrieved 2017-03-28.
  11. ^ RHCSA & RHCE Red Hat Enterprise Linux 7: Training and Exam Preparation Guide (EX200 and EX300), Third Edition Paperback – 27 Mar 2015 by Asghar Ghori