Stale NBs are left when deleting the underlying K8S cluster

[julsemaan]

General:

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Bug Reporting

When using the Linode CCM in K8S clusters and deleting the underlying cluster while not deleting the Service leaves a stable NB in the Linode account.

Expected Behavior

Explore having some kind of finalization mechanism to delete the NB when the cluster is being deleted

Actual Behavior

Stale NBs are left in place

Steps to Reproduce the Problem

1. Create a K8S cluster with the linode-ccm installed on it
2. Provision a Service of type LoadBalancer
3. Delete the control plane and nodes of the cluster

Environment Specifications

This happens for KPP clusters but also was reported by externally facing customers who are not using KPP

Additional Notes

I'm not really sure we can address this in the linode-ccm and may need to address it at a platform level but wanted to have this logged and tracked somewhere

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[luthermonson]

any thoughts on what we could catch to make this happen? this is happening outside of kube so we can't use the lifecycles in the ccm... my only thought is if the vms are deleted via the linode api we'd have do some reconcile with nodebalancers e.g. if their underlying nodes dont exist any more we delete the nodebalancer. open to suggestions @schinmai-akamai any other ideas ?