interface renaming (was: Re: Moving towards NetworkManager)

Josef Wolf jw at
Sat Jul 30 12:03:24 UTC 2016

On Sat, Jul 30, 2016 at 09:14:28PM +1000, Karl Auer wrote:
> All non-trivial changes have side-effects and require things to be
> adjusted and adapted to. They are *supposed* to make a difference.

That's true.

OTOH, what good is a non-trivial change if it (maybe) improves some rare-cases
but complicates 99% of all the other cases?

> I had an old Thinkpad once that for some reason I never understood came up
> with eth1 and wlan1 instead of eth0 and wlan0.

Well, maybe it would have been making sense to investigate (and fix) that?

> Maybe the move to predictable interface names will have a positive
> side-effect - removing some unwarranted assumptions from install

The question is: what EXACTLY does "predictable interface name" mean?

For me as a average user, ethX was PRETTY MUCH predictable

For me as a maintainer of automatic system/network configuration, ethX was
PRETTY MUCH predictable

For the maintainers of the snort package, eth0 was PRETTY MUCH predictable.

I don't find the wild combination of digits and letters predictable at all...

In the old days, I simply did "ifup eth0"

Nowadays, I do:
- "ifconfig -a"        # to find out the interface name
- "ifconfig -a | less" # the previous command scrolled out of the screen
- search for the relevant entry
- need to find my glasses to read the exact combination of letters/digits
- "ifup e76rthf8       # finally

Yeah! That's what "predictable names" mean in my day-to-day basis

Josef Wolf
jw at

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