On Sun, Mar 10, 2019 at 08:33:43PM +0100, Gert Doering wrote: [...] > On a system that only has one ethernet card, it's highly annoying > that I have to figure out if this is a "em0" or "igb0" - or an > "eno1" vs. "enp0s25" (both "onboard ethernet 0", but BIOS tables > leading udev to believing the second one isn't). So "eth0, always" > would be very convenient. Or possibly "eth0" for "wired ethernet" > and "wifi0" for wireless - as that's a common scenario.
Nowadays I'm pretty sure that so-called "predictable interface names", dependent on physical layout of mainboard was a terrible mistake. Hardware itself doesn't guarantee consistent and dependable behaviour, especially between different vendors. Some examples: onboard ethernet card on my mainboard was identified as enp0s25 but inserting SERIAL controller (four RS232 ports) into PCIe slot lead to renaming onboard interface to... enp16s0. Why? I have no clue. Friend of mine has two-ports Intel card. Internally implemented as two different PCIe functions and available as... enp0s0f0 and enp0s0f1d1 (but it is subject to change between different kernel versions 8-0). With a brand-new mobo there is no chance to guess interface name without test run. Classic Linux behaviour has two possibilities: simply "eth0" in any case or interface renaming based on MAC-addresses (fortunately MAC addr is usually known). BSD names also gives us a chance - usually we know something about network card manufacturer. -- Piotr 'aniou' Meyer
