Done When the enhancement for install time support is written and reviewed by stake holders.

Some notes from discussions:

• Install-config.yaml has an option to enable OCL
• Bootstrap MCO can parse MOSC yamls for master and worker nodes
  • An image is built for each pool and then rolled out onto the nodes

Installer Process:

• First step: Installer (openshift-install) generates manifests
  • Runs on local machine and generates items needed to start the installation process

• Second step: Bootstrap node comes up and parses generated manifest
  • Content and objects needed to create master nodes is processed during this step
  • Bootstrap MCO process runs on any MCO objects existing in the installation directory

• Third step: Master nodes create content and objects needed to spin up worker nodes

What needs to be done for OCL:

• Field in the install-config.yaml to manage enabling OCL
• MOSC yaml created in the installation directory
  • In future, generate an MOSC when one is not provided
  • Bootstrap MCO will parse this
  • Should contain all secrets, containerfiles, and specs needed for image build
  • 2 yamls should be created, one each for the master and worker pools
  • For now, require users to create an MOSC when OCL is enabled in the install-config.yaml
    • In future, generate an MOSC when one is not provided

• Bootstrap MCO parses the master MOSC yaml
  • This process will be started after the first rendered MachineConfig is created
  • Run a registry on the bootstrap node to host the build master mcp image
    • Given we will host the registry on the node, what image pushspec will be used in the MOSC? 
    • Maybe, it is something we generate and keep track of
  • Build pod to build the image is created
    • Should MOSB be created here?
    • Need to see if current process can just be used for bootstrap node
  • Once build is done, image is pushed to registry running on bootstrap node
  • Once the master nodes are up with current version of RHCOS, do a bootc switch or rpm-ostree rebase to boot into the built image

• Bootstrap node cannot communicate with worker nodes
  • Bootstrap node created the master nodes
  • The master nodes then create the worker nodes
  • Communication is only possible between bootstrap and master nodes and between master and worker nodes
  • Does the bootstrap node or installer create the master nodes?

• Master nodes parse the worker MOSC yaml
  • Can use external registry here for build image or imagestream (while it is still available)
  • MOSB generated and build job created
  • Once build is done, image is pushed to registry
  • Once the worker nodes are up with current version of RHCOS, do a bootc switch or rpm-ostree rebase to boot into the built image

• Build and rollout failures

• • Handle failures the same way we handle any installation failures today
    • The installation has to be cleared out and started again
  • Gather more data into the install log bundle related to the OCL process

Questions:

• Do we want to make the bootstrap be able to install itself via a container image eventually?
• Do we want to be able to boot into the container image built directly instead of having to do a switch or rebase?
• Do we want to make image mode the only path and remove ignition completely?
• Consider how this would hook into hypershift

Relevant code paths:

• https://github.com/openshift/installer/blob/main/data/data/bootstrap/files/usr/local/bin/bootkube.sh.template 
• https://github.com/openshift/installer/blob/main/pkg/asset/ignition/bootstrap/bootstrap.go 
• https://github.com/openshift/machine-config-operator/blob/master/pkg/operator/bootstrap.go
• https://github.com/openshift/machine-config-operator/blob/master/pkg/controller/bootstrap/bootstrap.go#L124-L159

T-shirt size:

• Enhancement: S
• Implementation: L