openshift-provisioning-workflow

name	openshift-provisioning-workflow
description	High-level overview of the OKD cluster setup process. Use this to understand the end-to-end flow from planning IPs and DNS to starting the VMs.

OKD Cluster Setup (High-Level)

This skill covers what is done at a high level for setting up our OKD cluster. It's simple and focuses on the main steps.

How it's run

All of these tasks are done through the Makefile in the okd/ directory. The Makefile does the heavy lifting for us by running bash scripts and Ansible playbooks behind the scenes.

1. Versioning is Everything

The openshift-installer version used when creating the ISO is very important. Each OpenShift/OKD release comes with an openshift-installer binary specific to that version. The version of OKD has a 1-1 relationship with the openshift-installer.

2. Infrastructure Pre-reqs

• IP Planning & DNS: We must know the IPs of our soon-to-be nodes. This has to be planned out and done. Update the DNS server for the cluster if it hasn't been updated yet via make update-dns.
  • Refer to homelab-dns-context skill for more context on the dns setup.
• API Load Balancer: You must create the Nginx load balancer for our soon-to-be cluster API server. It load balances between the 3 nodes and provides the IP that our DNS points to for our API domains.
  • Refer to openshift-api-loadbalancer skill for more context on the load balancer setup.

3. The Setup Flow

• Install the Binary: We install the correct version of the openshift-installer.
• Make Configs: We make an install-config and an agent-assisted installer config. This is done for us in the makefile (via make build or make agent-iso, however, make build is prefered).
• Create the ISO: We use the openshift-installer binary to create an ISO that will be used by all 3 of the VMs that act as nodes (via make build).
• Copy the ISO: We copy the generated ISO from our laptop to the server that will be running the nodes. The nodes are straight-up Linux VMs running on our desktop-server (via make copy-iso).
  • Refer to homelab-hardware-context skill for more context on the server.
• Start the VMs: We use that ISO to actually create and start the VMs on our server (via make start-vms).
  • Refer to openshift-node-setup skill for more context on the nodes.

And boom! Our cluster has our nodes, the DNS setup, and the API load balancer setup.