Comment 14 for bug 1997922

I understand what you're trying to accomplish and how that doesn't work with cloud-init, but I think we want a different approach than what you've specified in your patch. Cloud-init was never intended to be run on a device like a switch, and so on one hand this feels outside the scope of something cloud-init should be dealing with. On the other hand, we do understand that there are some limited use cases where duplicate mac addresses may be valid. Rather than adding one-off driver checks, we'd like to add something a little more general-use.

We can add a config option in /etc/cloud/cloud.cfg named something like "warn_on_duplicate_mac", which when set to true will warn rather than traceback. Will this work for you?