[systemd-devel] eth2: Failed to rename network interface 6 from 'eth2' to 'eno1': File exists

[Michael Biebl]

Am Mi., 5. Jan. 2022 um 13:50 Uhr schrieb Mantas Mikulėnas <grawity at gmail.com>:
> It does, yes, but note this part:
>
> Jan 03 11:30:14 nasl002b.example.com kernel: igb 0000:02:00.2 eth4: renamed from eth2
> Jan 03 11:30:14 nasl002b.example.com kernel: igb 0000:02:00.3 eth5: renamed from eth3
>
> Here the kernel-assigned names (eth2, eth3) are being renamed to custom names (eth4, eth5). That's not something systemd or udev does by default. It suggests that you likely have old "70-persistent-net" udev rules (or something similar) that assign custom eth* names separately from the slot-based "predictable" naming – perhaps a leftover from Debian 7.
>
> These interfaces aren't being skipped due to an earlier conflict – they are intentionally skipped by 80-net-setup-link.rules because they already have a custom 'NAME=' assigned by an earlier rule, so the "predictable" name is not applied to avoid breaking existing configuration.

Yes, please check if you have a leftover file
/etc/udev/rules.d/70-persistent-net.rules
See also the relevant NEWS entry in /usr/share/doc/udev/NEWS.Debian.gz

systemd (220-7) unstable; urgency=medium

  The mechanism for providing stable network interface names changed.
  Previously they were kept in /etc/udev/rules.d/70-persistent-net.rules
  which mapped device MAC addresses to the (arbitrary) name they got when
  they first appeared (i. e. mostly at the time of installation). As this
  had several problems and is not supported any more, this is deprecated in
  favor of the "net.ifnames" mechanism. With this most of your network
  interfaces will get location-based names. If you have ifupdown, firewall,
  or other configuration that relies on the old names, you need to update
  these by Debian 10/Ubuntu 18.04 LTS, and then remove
  /etc/udev/rules.d/70-persistent-net.rules. Please see
  /usr/share/doc/udev/README.Debian.gz for details about this.

 -- Martin Pitt <mpitt at debian.org>  Mon, 15 Jun 2015 15:30:29 +0200