Comment 12 for bug 1770082

Right. Yes, I can replicate that, thanks heaps!

So to summarise, you can make the rename take effect on boot if you:
 1) copy the files from /run/systemd/network -> /etc/systemd/network
 2) then update-initramfs -u

This seems pretty far outside of the way that netplan is supposed to work -
indeed using /etc/systemd/ is basically bypassing netplan. So we still have
the issue that just changing 'set-name' in /etc/netplan/*.yaml doesn't work
as expected. What should we change so that set-name works as expected?

I see a few options:

 0) Document that set-name is fragile and stop relying on it. This is
actually really easy to do and I have a netplan patch drafted already. The
reason that we have no network connectivity when set-name fails is that the
network file netplan creates maches on *both* the new name and the mac
address. We can just drop the new name from the [Match] section of the
relevant .network file and match only on the provided mac address (or
whatever else was used in the netplan match stanza). This means that
regardless of the interface name it's brought up and networking works.

 1) Make the initramfs hook for udev copy the files from /run (as well as
from /lib and /etc) into the initial ramdisk. This is probably my
preference; we can run netplan generate beforehand to make sure we get a
clean copy, and then document that update-initramfs is required to get
stuff to stick.

 2) Allow udev to re-rename interfaces. I don't know if this would be
acceptable to systemd upstream?

 3) Something else?

Regards,
Daniel