[systemd-devel] Udev won't rename interfaces that are already UP

[Tom Gundersen]

On Wed, Feb 18, 2015 at 9:36 PM, Reindl Harald <h.reindl at thelounge.net> wrote:
> Am 18.02.2015 um 21:29 schrieb Giancarlo Razzolini:
>> It is my perception that if you are using predictable network interface
>> naming, which is the current default, you can safely make your network
>> configuration use the changed interfaces names to be sure they'll get
>> the desired interface. This applies to network configuration, firewall
>> rules, whatever
>
> predictable? go away!

I think you know he was referring to:
http://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames/

Maybe you disagree with the use of the word 'predictable', but that's
what the scheme is called, so let's just stick to that (maybe thinking
of it as 'deterministic' would make it more palatable).

> on any machine i know running network.service (the old style)
> ethX is predictable and the new "predictable" changed multiple times and
> frankly there are configurations re-used on a dozens of machines where i
> know in case of *all of them* that eth1 is *always* the WAN interface

Good. Then disable the logic. But please understand that in general it
is not possible to know whether eth0/eth1 will be switched between
reboots. Our default logic must work in general, not only on specific
machines, which is why it is the way it is.

Cheers,

Tom