[gentoo-user] eno1 became back eth0

[Michael Haubenwallner]

Hi Alarig,

On 11/13/19 5:54 PM, Alarig Le Lay wrote:
>
> PS: Old interface names were way more guessable than the new ones (eth0
> used to work 99% of time). I really don’t understand why someone woke a
> morning a though “we should randomise this, it’s too much stable”.

While I've no idea about why your dev manager seems to not pick up the
task to rename the network devices, the reason behind the rename is:

Especially server machines may have multiple network devices, maybe
even built with different hardware requiring different kernel drivers.
Now the device initialization is performed in parallel, but the ethX
naming scheme does require serialization to get unique device names,
causing the device being initialized fastest to receive the name eth0.

But on another reboot, another device may be faster, and you end up with
eth0 and eth1 being toggled this time.  For example, I have discovered
this to be fatal for virtualization hosts, when virtual guest's network
devices need to be bound to a specific host device.

What usually does not change across reboots is the physical location of
network devices, and the firmware.  So the new naming scheme is based on
their physical location in the machine's hardware layout.  For example,
unless configured otherwise, on board devices that are enumerated by the
firmware receive the enoX name, and PCI devices receive some enpXsY name
with some physical PCI connector numbers as reported by the PCI firmware.

But agreed, eth0 name is "stable" if there is one single network device.

HTH,
/haubi/