Maybe I should also read the documentation I link to …
“list of attribute names”, so no we can’t put a variable in there, that’s not an attribute to the instancwe resource.
Can you try setting userdata
as ignore?
lifecycle {
ignore_changes = [
tags,
userdata
]}
So we ignore not the changes in input parameters but the resulting changes in tags and userdata. That’s probably how it’s intended to work.