[CentOS] CentOS 7 : network interface renamed from eth0 to eth1 after reboot

Mon Feb 10 01:28:29 UTC 2020
Stephen John Smoogen <smooge at gmail.com>

On Sun, 9 Feb 2020 at 13:51, Nicolas Kovacs <info at microlinux.fr> wrote:

> Le 09/02/2020 à 16:54, Alexander Dalloz a écrit :
> > "Kernel always uses the ethX naming convention at boot when it
> enumerates
> > network devices. Due to parallelization, the order of the kernel
> interface
> > enumeration is expected to vary across reboots."
> Thanks for the heads up.
> I experimented quite a bit, and found some surprising behavior. So I
> documented
> everything in a little blog article.
>    * https://www.microlinux.fr/interfaces-reseau-persistantes/
> Cheers,

So yeah if there are certain cards, certain bios firmware, the eth? are not
guarenteed. The upstream kernel will say it is not a bug as everything is
doing what it is doing, and will point out various things where eth? is
really an internal kernel representation which is only accurate by luck.
What you are supposed to do is rename the interface (I think the docs I
found said net0 or whatever you want) and link the two via udev or similar
rules. That way the udev sets up and sees 'this pci/network is blah.. alias
it to net0 and pass that so the scripts work. Then network-scripts or
networkmanager or whatever sets up and down net0 versus a 'semi-random' eth
interface. [For kernels beyond 4.?? and beyond I am expecting that this
will be a more stringent requirement]

Stephen J Smoogen.