Eth0 renamed to end0 in core24 image

I have recently built a Ubuntu Core 24 based image for Raspberry Pi based hardware. After booting I see that eth0 has been renamed to end0.

It seems to be suggested (for Non Ubuntu COre systems) that putting net.ifnames=0 in /boot/cmdline.txt will revert this.

This solution doesnt work on Ubuntu Core. Is there an alternative mechanism to disable this “Predictable Interface Names” mechanism.

It used to (it works in Core22) :slight_smile: but seems systemd dropped support for it, though I can’t actually find with which version but it looks like the documentation referring to it:

https://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames/

has been deprecated about a year ago in favor of:

https://www.freedesktop.org/software/systemd/man/latest/systemd.net-naming-scheme.html

To configure this feature, is it correct to change the cmdline.txt-core in the gadget snap source which end up in /run/mnt/ubuntu-seed/cmdline.txt on the imaged system?

There are other instances of cmdline.txt on the imaged system , not all identical.

Also should changing it and rebooting be enough or does the gadget snap need to rebuilt and the device re-imaged?

As I understand the doc you need to use a udev rule in the the new world, but yes, cmdline changes should go into the -core file afaik

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