This command offers all required functionality to provision an host to join a Kubernetes cluster.

The following operating systems are supported

• Ubuntu 18.04
• CentOS 7
• ContainerLinux / CoreOS (Not tested with RedHat CoreOS)

• The cluster needs to use the bootstrap token authentication

./provision \
    --kubelet-version="v1.13.1" \
    --cloud-provider="openstack" \
    --cloud-config="/etc/kubernetes/cloud-config" \
    --token="AAAAAAAAAAAAAAAA" \
    --ca-cert="/etc/kubernetes/ca.crt"

Nodes will boot with a cloud-init (Or Ignition) which writes required files & a shell script (called setup.sh here).

Parts which will be covered by cloud-init (or Ignition)

• Install SSH keys
• Configure hostname
• ca.crt The CA certificate which got used to issue the certificates of the API server serving certificates
• cloud-config A optional cloud-config used by the kubelet to interact with the cloud provider.
• setup.sh
  Is responsible for downloading the provision binary and to execute it. The download of the binary might also be done using built-in cloud-init (or Ignition) features

The provision binary will identify the operating system and execute a set of provisioning steps.

The provisioning process gets separated into 2 phases:

• Base provisioning Install and configure all required dependencies
• Join Write & start the kubelet systemd unit

The following steps belong into the base provisioning:

• Install required packages (apt & yum action)
• Configure required kernel parameter (Like ip forwarding, etc.)
• Configure required kernel modules
• Disable swap
• Download & install the CNI plugins
• Download & Install docker
• Download Kubelet
• Install health checks (Kubelet & Docker)

This part will:

• Write & start the kubelet systemd unit

The provision binary should also be usable for "prebaking" images, which then can be used for offline usage.

To make sure the local development version of the provision command gets used for new machines created by the local running machine controller, a new flag --provision-source must be introduced. This flag will instruct the machine controller to download the provision binary from the specified location.

For simplicity the /hack/run-machine-controller.sh will be updated to include a step which will compile the provoision command & upload it to a gcs bucket.