Hi Michael,

On Tue, 27 Jul 2021 10:15:28 +0200
Michael Walle [off-list ref] wrote:

Why do we have to distiguish between LEDs connected to the PHY and LEDs
connected to the MAC at all? Why not just name it ethN either if its behind
the PHY or the MAC? Does it really matter from the users POV?

Because
1. network interfaces can be renamed
2. network interfaces can be moved between network namespaces. The LED
   subsystem is agnostic to network namespaces
So it can for example happen that within a network namespace you
have only one interface, eth0, but in /sys/class/leds you would see
  eth0:green:activity
  eth1:green:activity
So you would know that there are at least 2 network interfaces on the
system, and also with renaming it can happen that the first LED is not
in fact connected to the eth0 interface in your network namespace.

Marek