Kubernetes Terraform EC2 Example

This repo is created to flesh out my understanding of Kubernetes + Terraform through creating a basic K8s cluster using AWS elements + EC2 Many elements of this are insecure, to allow this to be spin-up, spin-down when needed for further experimentation, It is not intended to remain up, hosting a prod-like workload.

• AWS Kubernetes
  • Updates
  • Description
  • Dependencies and Setup
  • Notes
  • Planned Changes

Updates

• 2022.08.04 Updated with bearer token access conditionally enabled, allowing remote apiserver access
• 2022.07.26 Security Groups, Routing Table + VPC, Token Random Generation for Init, worker node join
• 2022.07.11 Readme + Initial Controller EC2 Instance

Description

Why not use the EKS? I would generally use EKS on AWS, but the purpose of this module is to explore all of K8s, Rough Edges includes. Possibly as a basis for further exploration of Kubernetes in the future.

Dependencies and Setup

Set up AWS CLI Install Terraform

To access Kubernetes cluster remotely, install kubectl and access the cluster remotely with:

kubectl -s="https://<controller-node-ip>:6443" --token=<tokenName - default "insecureToken"> --insecure-skip-tls-verify=true get nodes

Notes

With the stated goal of this module being a learning experience, this section contains the (changing) high-level detail of k8s setup with terraform and any relevant/useful details.

Planned Changes

• Provision EC2 Controller Node
  • Pre-requisite setup
  • Generate kubeadm init token from terraform natives
  • Kubeadm based installation
  • output variables for other node's setups
  • Install basic CNI
    • Calico as it supports ingress
• Setup n amount of worker nodes
  • Requires output vars from controller
  • Setup with kubeadm
  • Join with kubeadm string
  • ~~2nd Worker Node ~~
  • N Amount of Nodes based on input?
• Open up security groups
  • Requires output vars from controller + workers
  • Auto create the groups and add workers/masters.
• Demo basic webapp on module
• Additional Changes:
  • Clean up init script
  • Make the module instantiable (e.g. populated example folder, take out hardcoded dependencies that makes this personal rather than templated)
  • Scaling worker nodes (horizontally) based on demand
  • Resilience
  • ~~Bearer token on init, allowing (very insecure) access. ~~
    • This could allow for HELM access via the terraform provider in external projects and/or immediate remote API access.
    • ~~Very insecure, but this is not a prod-like implementation. ~~