Is there a way to get notified (e.g. via e-mail) when

system-upgrade-controller

performs an update? I need some kind of audit trail + notification system.

No, that would probably best be a job for a logging+alerting system

OK, do you know of any good ones that I should look into?

The SUC pod will log when it takes action, you could trigger an alert off that

I have made a prepare step that sends a pushover notification when it starts upgrading. You could do something like that, but it's not really elegant 🙂

I don't understand what you mean by "prepare step".

SUC is not really well documented, but a plan can have a

prepare

step, which runs a command in an image. The k3s-upgrade plans use a prepare step in the agent plan, but not on the server plan. So I added my own prepare step to the server plan that just runs a scripts that sends a pushover notification.

Oh, I see. So it's kind of like an unused hook. I see why it's not elegant, and why it works. Thanks for the tip! It would be awesome to be able to add our own "pre-upgrade" hooks that do not override the

prepare

step.