Unlike previous teardown scripts, tearing down a live Kubernetes cluster and returning it to a vanilla state can not happen host-by-host. You can still add and remove hosts from the cluster (though we'd be cautious about removing hosts with Longhorn actively managing storage), but once you get into the live cluster layer you begin to abstract away the differentiation between hosts, and start to reason with the cluster as one single entity.
As such, tearing down a live cluster is better thought of as simply uninstalling the software we just installed.
In standing up a live k3s cluster we used an Ansible script to install 4
essential apps. We did this because the installation order was important, and
the apps were fairly cut and dry. Because the installation order matters, so
does the order by which we uninstall these apps. As you browse
K3s/teardown-live.yml keep this in mind.
Further, if you have additional apps, like Bitcoin running, on top of your live cluster you should not tear down the live cluster. First, you must uninstall those apps. Think about it like this: running teardown live without first backing up, and uninstalling, all your apps and data would be akin to installing a new operating system on your laptop without first backing up all your apps and data, and expecting those apps to still work and the data to still be there.
Do not run
K3s/teardown-Live.yml while any layer 3 apps are running.
To teardown a live cluster (with no additionally installed apps running) run: