Building an On-Premise Kubernetes Cluster — Part 1: Preparing the Environment

🇧🇷 Leia a versão em português aqui This is the first part of a series where I'll share, step by step, how I built my own on-premise Kubernetes cluster, without relying on any cloud provider. The goal is to document the whole process — from environment preparation to a working cluster — as a reference for anyone studying the topic or looking to replicate the same setup at home or at work. I used VPS (Virtual Private Server) and VM (Virtual Machine) for this cluster. However, it can also be set up on physical machines (Bare Metal). Bye the end of this series, it will be easier to understand cloud clusters on AWS (EKS), Google (GKE) and Azure (AKS). In this first part, we'll cover everything needed before installing any Kubernetes component: hardware requirements, basic network configuration, firewall rules, and a few mandatory operating system adjustments. Requirements The following topology was used for this cluster: 3 servers in total 1 master server (control-plane): 2 CPUs (cores) and 2 GB of RAM 2 worker servers (slaves): 1 CPU and 1 GB of RAM each Root access on all machines This is a minimal setup, ideal for study, lab, or testing environments. For production, resources should be scaled according to expected load. Configuring the hosts file Before installing anything, it's important for the machines to resolve each other by name, not just by IP. Edit the /etc/hosts file on all servers and add the corresponding entries: 10 . 0 . 10 . 100 master . company . local master 10 . 0 . 10 . 101 slave01 . company . local slave01 10 . 0 . 10 . 102 slave02 . company . local slave02 This ensures that, later on, the Kubernetes components can correctly resolve node names. Configuring the Firewall Kubernetes depends on specific ports being open between nodes so the control-plane can communicate with the workers (and vice versa). The ports vary depending on the server's role in the cluster. On the master server: Port Protocol 6443 TCP 2379-2380 TCP 10250 TCP 10251 TCP 10252 TCP