Re: Ethernet trouble

[Bob Weber <bobrweber@gmail.com>]

On 1/29/20 12:05 PM, ghe wrote:

> On 1/29/20 8:04 AM, Curt wrote:
>
> > 'p' indicates the PCI bus and 's' indicates the slot, was my
> > understanding of the naming scheme. 
> >       
> Yeah. That's what I was told too.
>
> > Would a BIOS/Firmware upgrade
> > modify the PCI bus and slot number of your Ethernet ports?
> >       
> I doubt it. SuperMicro's BIOS writers aren't that stupid. I certainly
> hope they aren't.
>
> Besides:
> 1) There was no change to the BIOS.
> 2) The interfaces weren't moved anywhere. They're still soldered to the MB.
>
>

I have struggled with this for hours before.  The systemd naming convention is explained at:

https://www.freedesktop.org/software/systemd/man/systemd.link.html

Pay attention to the Examples near the bottom of the page.  There are udevadm commands that you can help you check the configuration.   I ended up with the four following configurations:

1.  kernel command line option in grub add "net.ifnames=0"

2.  /etc/systemd/network/10-eth0.link:

[Match]
MACAddress=00:xx:xx:xx:33:ce

[Link]
Name=eth0

3.  /etc/systemd/network/10-eth0.link:

[Match]
MACAddress=00:xx:xx:xx:33:d2

[Link]
Name=eth1

4.  And finally:

/etc/systemd/network/99-default.link  linked to /dev/null

This is my main router machine so these names have to be the same on every boot so the firewall rules work as desired.  There also seems to be bugs in systemd (I use testing) so that these appear to not work.  I think the key was setting 99-default.link to /dev/null.

Hope this helps.

--


...Bob