Libvirt Kubernetes (k8s) Module

This module deploys Kubernetes master and worker nodes as libvirt VMs. It then uses the testbox VM created by the libvirt-infra module to run kubekey and install a Kubernetes cluster on these nodes.

Architecture

This module builds upon the infrastructure provisioned by the libvirt-infra module and performs the following actions:

1. Provisions Kubernetes Nodes: Creates the specified number of master and worker node VMs using a base Ubuntu cloud image.
2. Configures Nodes with Cloud-Init: Uses cloud-init to set up basic node configuration, including adding the public SSH key from the testbox for access.
3. Installs Kubernetes using KubeKey:
   • Generates a kubekey configuration file (kubekey.yaml) based on the provided variables.
   • Copies the configuration and an installation script to the testbox VM.
   • Executes the script on the testbox to trigger the kubekey installation process across all newly created nodes.
4. Retrieves Kubeconfig: After a successful installation, it retrieves the kubeconfig file from the testbox, modifies the API server address to point to the libvirt host (as configured by the libvirt-infra module's port forwarding), and saves it locally.

Usage

This module is intended to be used after the libvirt-infra module has been successfully applied.

terraform init
terraform apply

Upon successful completion, the kubeconfig file for your new cluster will be available in the output directory within this module's path.

Requirements

Name	Version
terraform	>=1.6.5
libvirt	0.7.6
remote	0.2.1

Providers

Name	Version
libvirt	0.7.6
local	2.5.3
null	3.2.4
remote	0.2.1

Modules

No modules.

Resources

Name	Type
libvirt_cloudinit_disk.masters	resource
libvirt_cloudinit_disk.workers	resource
libvirt_domain.masters	resource
libvirt_domain.workers	resource
libvirt_volume.masters	resource
libvirt_volume.masters_base	resource
libvirt_volume.workers	resource
libvirt_volume.workers_base	resource
local_file.k8s_install_script	resource
local_file.kubeconfig	resource
local_file.kubekey_config	resource
null_resource.testbox_install_k8s	resource
remote_file.kubeconfig	data source

Inputs

Name	Description	Type	Default	Required
disable_kube_proxy	disable kubeproxy	string	"true"	no
image_download_base_url	the base url of the images	string	n/a	yes
k8s_version	the version of the k8s	string	n/a	yes
libvirt_host_ip	The IP address of the libvirt host.	string	n/a	yes
libvirt_pool_name	The libvirt pool name.	string	n/a	yes
libvirt_private_network_id	The libvirt private network id.	string	n/a	yes
libvirt_root_private_key_path	The private key path of the libvirt host.	string	n/a	yes
masters_info_list	The list of master nodes.	list(object({ ipv4 = string ipv6 = string mac = string hostname = string }))	n/a	yes
nodes_os_image_name	the name of the os image	string	"ubuntu-22.04.3-kernel-5.15.0-92.iso"	no
testbox_info	the testbox info	object({ public_ip = string username = string public_port = string private_key = string public_key = string })	n/a	yes
workers_info_list	The list of worker nodes.	list(object({ ipv4 = string ipv6 = string mac = string hostname = string }))	n/a	yes

Outputs

Name	Description
k8s_api_server_ip	n/a
path_to_kubeconfig_file	n/a