[systemd-devel] Predictable Network Interface Name Bug?

[Zbigniew Jędrzejewski-Szmek]

On Wed, Dec 15, 2021 at 09:37:41PM -0500, Tim Safe wrote:
> Hello-
> 
> I have an Ubuntu Server 20.04 (systemd 245 (245.4-4ubuntu3.13)) box that I
> recently installed a Intel quad-port Gigabit ethernet adapter (E1G44ETBLK).
> 
> It appears that the predictable interface naming is only renaming the first
> two interfaces (ens8f0, ens8f1) and the second two fail to be renamed
> (eth2, eth3).
> 
> From the logs, I see the following messages:
> 
> systemd-udevd[456]: eth2: Failed to rename network interface 5 from 'eth2'
> to 'ens8f0': File exists
> systemd-udevd[456]: eth2: Failed to process device, ignoring: File exists
> systemd-udevd[459]: ethtool: autonegotiation is unset or enabled, the speed
> and duplex are not writable.
> systemd-udevd[459]: eth3: Failed to rename network interface 6 from 'eth3'
> to 'ens8f1': File exists
> systemd-udevd[459]: eth3: Failed to process device, ignoring: File exists
> 
> Taking a closer look at the PCI bus, I see:
> 
> 05:00.0 Ethernet controller: Intel Corporation 82576 Gigabit Network
> Connection (rev 01)
> 05:00.1 Ethernet controller: Intel Corporation 82576 Gigabit Network
> Connection (rev 01)
> 06:00.0 Ethernet controller: Intel Corporation 82576 Gigabit Network
> Connection (rev 01)
> 06:00.1 Ethernet controller: Intel Corporation 82576 Gigabit Network
> Connection (rev 01)
> 
> It looks like the adapter has two instances ending in '0' and two instances
> ending in '1'; they differ by the higher number ('05' vs '06') in the lspci
> output.
> 
> Is this a bug? I'd expect to see the 3rd and 4th interfaces to be named
> ens8f2, ens8f3.

Can you provide the output from 'udevadm test-builtin net_id /sys/class/net/<iface>'
for each of the four interfaces?

Zbyszek