Each VM instance runs on KVM and is initialized using Cloud-Init with a Debian 12 cloud image. Subsequently, the instances are managed by libvirt and its command-line utilities. The Kubernetes services within each VM are controlled by Systemd.
The communication between components in the cluster is protected by TLS. A CA is created as part of the process and certificates are issued using OpenSSL and deployed in each server. The implementation can be found here: scripts/plugins/tls.sh and the configuration template files in this place: extras/tls/
The script is structured around a core library that handles primary functionalities such as creation and destruction fo clusters, complemented by a suite of plugins that offer customization options for the stack.
The script uses a configuration file named db.txt that outlines the components of the cluster and guides the actions necessary for its creation. This file is generated when a new cluster is created using the new command and is updated whenever a new worker node is added using the add command.
cluster.sh is a command-line script that integrates the cluster management library to offer functionalities such as creation, destruction, startup, and shutdown of clusters, among other options.
extras is a directory that contains configuration templates, OpenSSL config templates, and other support files.
- api.sh: This library offers a public API for cluster management.
- controller.sh: Implementation of the api.sh public API.
- Makefile.vm: Makefile that support the creation and destroying of VM.
This directory contains the necessary files to access db.txt, which guides the cluster creation process. As part of this process, a cluster.txt file is created with information about the infrastructure to be deployed. Access to both files is managed by libraries present in this directory.
- host.sh: Contains functionality for updating the host files of both the local machine and the cluster's VMs.
- local.sh: Provides services for setting up the local machine.
This folder contains utilities libraries used by the different parts of the system.
- haproxy.sh: It provides functions to generate haproxy and keepalived configuration files and deploy them on the load balancer VMs.
- kvm.sh: It enables the creation, removal, and administration of virtual machines (VMs).
- net.sh: It includes functionality for configuring new routes for the cluster's virtual machines (VMs).
- tls.sh: It implements the functionality for generating the Certificate Authority (CA), issuing certificates, and deploying them.