See issue #6079 as the roll-up for node upgrades.

While the basic mechanisms (#6099, #6088) will be an out-of band process in Bash, we would like to have the mechanism be written in Go and hook into pkg/cloudprovider.

Aside from being generally more robust and maintainable, this will mean that our deployment and upgrade mechanisms can share code (as both move towards pkg/cloudprovider support). Also, hosted solutions can then upstream and share code for deployment and upgrades.

References:

• It was first mentioned in upgrade: Make node components upgradeable (at all possible) #3333 in this comment that we don't want the upgrade mechanism to be a tangled mess of Bash scripts.
• The kubedeploy tool, which is related to sharing code for cluster-level operations and Bash → Go tooling, was proposed in Proposal to rework Kubernetes deployment CLI #5472.