CentOS - Sep 2014 - Centos 7 + SystemD + Predictable Network Interface Names

Hi list,
I'm trying Centos7 and using systemD. I've noticed that interfaces name 
does not have anymore eth0,eth1, ethN but a different name.

What do you think about predictable network if name assigned by systemd?

On Wed, Sep 24, 2014 at 10:04:39AM -0400, Alessandro Baggi
wrote:
> Hi list,
> I'm trying Centos7 and using systemD. I've noticed that interfaces
> name does not have anymore eth0,eth1, ethN but a different name.
> 
> What do you think about predictable network if name assigned by systemd?
For what its worth, there was a change in device naming in CentOS 6
(going from eth0 -> em1, for example) which affected a subset of
hardware out there (We saw it on Dell hardware, mostly).  We had
already managed to deal with the fact tha 'eth0' is no longer
guarenteed (in scripts, usually by looking in /sys/class/net/), so
dealing with non-eth0-naming wasn't a huge surprise, however, the way
devices are named changed.  For what it's worth, I am not thrilled
with the incredibly complex names but I understand their utility.

There are a couple of ways to disable it listed here:
http://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames/



-- 
Jonathan Billings <billings at negate.org>

On Wed, Sep 24, 2014 at 9:04 AM, Alessandro Baggi
<alessandro.baggi at gmail.com> wrote:
> Hi list,
> I'm trying Centos7 and using systemD. I've noticed that interfaces
name does
> not have anymore eth0,eth1, ethN but a different name.
>
> What do you think about predictable network if name assigned by systemd?
>
No experience yet, but it will be very valuable to us if, in fact, the
names really are predictable in terms of matching up with the physical
connections on similar hardware.  Moving an installed disk to a
different chassis or restoring a backup on a different box can be
painful on systems with a large number of nics that are named in
essentially random order like the older systems.  So, I think it is a
great idea and should have been done that way from the start, but I'm
not convinced yet that it will really work on most hardware.

-- 
   Les Mikesell
     lesmikesell at gmail.com