nicholasdille / capictl

Bootstrap a self-managed workload Kubernetes cluster using Cluster API

capictl

This repository contains an opinionated script to create a Kubernetes cluster using the Cluster API on a few infrastructure providers.

🎉 This is the successor of k8s-caph-talos. 🎉

After creating a local bootstrap cluster, the workload cluster is created. At the end of the rollout, the management services are moved into the workload cluster.

The resulting cluster will be able to manage itself as well as create new clusters.

Supported infrastructure

Bootstrap clusters: kind, k3d

Infrastructure providers: docker, hetzner, vsphere

CNI: cilium

Usage

capictl supports a number of options to configure the cluster. The following command will create a cluster with the default configuration:

bash capictl -n my-cluster

The following settings are supported:

Option	Variable	Default	Description
-n	CLUSTER_NAME		The name of the cluster
-v	KUBERNETES_VERSION	(latest)	The version of Kubernetes to deploy
-b	BOOTSTRAP_CLUSTER_PROVIDER	kind	The provider for the bootstrap cluster (valid values are kind, k3d)
-i	WORKLOAD_PROVIDER	docker	The provider for the workload cluster (valid values are docker, hetzner, vsphere)
-p	CNI_PLUGIN	cilium	The CNI plugin to use (valid values are cilium)
-x	POD_CIDR	10.42.128.0/17	The CIDR for pods
-y	SERVICE_CIDR	10.42.0.0/17	The CIDR for services
-c	CONTROL_PLANE_NODE_COUNT	1	The number of control plane nodes
-w	WORKER_NODE_COUNT	2	The number of worker nodes

All variables can be configured through a .env file as well (including the provider specific variables described below).

The corresponding kubeconfig file is stored in the current directory as kubeconfig-${CLUSTER_NAME}.

The following provider specific variables are supported:

Hetzner

See the Hetzner Cloud provider documentation.

The following default values are configured:

Variable	Default	Description
HCLOUD_REGION	fsn1	The Hetzner Cloud region
HCLOUD_CONTROL_PLANE_MACHINE_TYPE	cx21	The Hetzner Cloud control plane machine type
HCLOUD_WORKER_MACHINE_TYPE	cx21	The Hetzner Cloud worker machine type

vsphere

See the vsphere provider documentation.

Prerequisites

The script relies on a number of binaries to work:

• docker
• envsubst
• jq
• kind or k3d
• kubectl
• hcloud
• clusterctl
• cilium

Those prerequisites can be installed with uniget.

Internals

This is how the script works:

1. Create a bootstrap cluster using kind or k3d
2. Initialize Cluster API in the bootstrap cluster
3. Generate a cluster configuration for the workload cluster
4. Wait for the control plane to initialize
5. Deploy Cilium
6. Deploy necessary components, e.g. cloud controller manager and CSI
7. Wait for the controle plane to be ready
8. Wait for the worker nodes to be ready
9. Initialize Cluster API in the workload cluster
10. Move the cluster configuration to the workload cluster
11. Create a kubeconfig for the workload cluster with a dedicated service account

TODO

• Talos
• Idempotency (being able to restart and pick up where it left off)
• Configure CIDRs for pods and services
• Test kubectl wait
• Support infrastructure docker?
• Support infrastructure vcluster?
• Check out Cluster API Operator