Bug#1105204: udev: networking broken by interface name change upgrading from bookworm to trixie enp1s0 -> ens1

[Emanuele Rocca]

Hi Michael,

On 2025-06-16 01:13, Michael Biebl wrote:
> On Thu, 5 Jun 2025 13:58:33 +0200 Emanuele Rocca <ema at debian.org> wrote:
> > Does this mean that all interfaces called enpXs0 on Bookworm will be
> > renamed to ensX when upgrading to Trixie?

> A way to address this issue could be, to freeze the naming scheme upon first
> installation of the system. Say you install a new bookworm system with
> systemd v252, you pin it to net.naming_scheme=v252.
> 
> Upgrading the system to trixie which has systemd v257, it would stay with
> the previous naming scheme.

Right, we could either recommend users to do that or to explicitly set
their network interface names to avoid surprises.

It would be great for folks to be able to predict (hehe) *before*
rebooting whether or not their network interface name will change. My
understanding is that there is no easy way to find out though, not
before one is running the new kernel and systemd, because it's only with
the upgrade of both the kernel (which sets new metadata) and systemd
(which uses it) that the renaming happens. Is that correct?