ifup bridge network configuration does not survive zypper dup 12.3 -> 13.1 possibly init -> systemd

I've spent about a week working through the pain of getting my network back into some kind of order following a zypper dup upgrade from 12.3 to 13.1.

The problem is this. Since I run several kvm instances I bridge my local NIC (eth0). So eth0 configured with a 0.0.0.0/32 address, and br0 bridging eth0 and configured through DHCP.

But after the upgrade, (and i suspect that the real culprit here is systemd as I was still deliberately on sysVinit in 12.2), it looked from the boot logs as if systemd was trying to start eth0 on it's own.

So I bring up my system, and all I have is a down'ed eth0 and a loopback.

I go into yast, where I see the bridge seemingly properly configured. Going through the menus triggers yast's network reconfig, which seems to do the trick .... until the next reboot, when all my settings yet again go away.

In the way this is what I ended up doing:

Boot the system into the multi-user.target (this is really annoying btw in how to do it now btw - it's not described anywhere that I could find and I ended up having to second-guess and find through directory trees to find a likely candidate)

Now once the system is back up, I only see lo0 and eth0 in ip addr.

Go into yast -> Network Devices and delete everything. Absolutely everything.

When you come out of yast, you'll see nothing has actually changed. yast doesn't seem to understand systemd networking (who actually does?)

So, I finally figured out there was a command that looked like

That actually got rid of my network for eth0.

Now, do yet another reboot.

So you've rebooted back. Now go back into yast, and set up the bridged configuration.

Reboot again (does this feel like Windows yet?)

This finally seems to work. At least so far. I shudder to think what will happen if I try to enable the wireless NIC on this box.