Support groups of nodes with a disctinct set of labels and taints (node groups)

[corvus-ch]

Summary

As a solution engineer I want to be able to provision cluster with mixed worker node sizes So that I can implement the customer's requirements

Context

Modify Terraform module for OpenShift4 on Exoscale to support mixed worker node types and document how to migrate existing cluster Terraform states to the new module version.

Further links

• Related issue for OCP4 cloudscale.ch Terraform module: https://github.com/appuio/terraform-openshift4-cloudscale/issues/22

Acceptance criteria

• OCP4 clusters on Exoscale with mixed worker node sizes can be provisioned by Terraform

Implementation Ideas

• Keep current worker config as "default worker group"
• Change Terraform module to accept additional worker group configurations as map of worker group name to worker group parameters (instance type, disk size, etc.) and instantiate the internal node-group module for each entry