1

After a reboot my network interface eth1 is now called p18p1 messing up my network setup. What causes this change of name?

I'm using Linux 4.0.5 on Ubuntu 15.04.

Kalle Richter
  • 2,192

1 Answers1

3

The newer kernel versions use a new numbering. This was changed to get a better consistency in network device numbering when adding new network cards. All new kernel versions use this new numbering, like enp4s6 instead of eth0. As Aaron pointed out, these are locations on the bus (PCI etc.), so unless the devices are plugged elsewhere they always get the same name, irrespective of other devices or scan order. Please see here for more rationale: http://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames/ .

These interfaces can also be renamed, please see here: https://askubuntu.com/questions/217635/how-to-rename-an-ethernet-interface .

The change was analogue to using disk/partition UUIDs instead of /dev/sda1 etc. - to keep everything working when adding new hardware.

Community
  • 1
Ned64
  • 8,726
  • One other interface kept the old name. When can one expect this renaming to be consistent for all interfaces and where is it documented (you mention enp4s6, my interface got renamed p18p1 - are those random digit or reflecting different types of interfaces (speed, medium, etc.)?) – Kalle Richter Jun 12 '15 at 23:01
  • 2
    No, they're the location on the bus. – Aaron D. Marasco Jun 13 '15 at 00:12