[systemd-devel] Better network naming on Hyper-V/Azure?

[Stephen Hemminger]

On Tue, 7 Jan 2020 15:01:25 +0100
Lennart Poettering <lennart at poettering.net> wrote:

> On Mo, 06.01.20 15:36, Stephen Hemminger (stephen at networkplumber.org) wrote:
> 
> > About a year ago there was some discussion on having persistent network names
> > on Hyper-V/Azure. Haiyang did some patches to add an attribute which
> > could be used by udev to do this. But there are some reluctance because
> > of how the channel id works.
> >
> > The motivation to provide network naming is to allow vmbus to change to parallel probing.
> > Right now probing is serialized so naming is always in same order.
> >
> > My question is what exactly does systemd/udev need to provide persistent
> > naming. The obvious ones are:
> >   1. Must be unique (although PCI slot isn't)  
> 
> It's not unique per bus? huh?

If you look in sysfs code, there is already code to handle
the case where two devices (usually sub-function) share the same PCI
slot. It is handled by adding a suffix in the kernel.