Taha-cmd / free-oke

Deploy a free kubernetes cluster in the oracle cloud

A bunch of very opinionated terraform modules and helper scripts to set up a free kubernetes cluster in the oracle cloud using only resources included in the free tier. The emphasis is on very opinionated because there isn't much room for configurability in the free tier.

Motivation

The goal of this project is mainly to mess around and learn more about Terraform, Kubernetes and different cloud providers.

❗ IMPORTANT ❗

This is intended for development and experimenting only! The provisioned infrastructure does not follow security best practices! Avoid using sensitive data!

Prerequisites:

• oci cli & account
• terraform
• powershell
• kubectl (optional)
• az cli & azure account (optional)

Modules

• oke: Creates a kubernetes cluster and the required networking infrastructure in the oracle cloud
• k8s: Installs an ingress controller and sets up a load balancer to enable inbound traffic for the cluster created in oke. It also contains optional scripts to help with https and dns.
• azure-pinger: Sets up an automation job in azure to constantly ping the kubernetes cluster, aims to generate network traffic to prevent the cluster from staying idle, because oracle reclaims idle instances.

Getting Started

Assuming that all prerequisites are met, follow these steps:

• Remove the .example from all *.tfvars.example files and fill them with your values.
• Run the following scripts

    # Deploy the oci infrastructure
    & Deploy-Module.ps1 -Module oke

    # Deploy the k8s infrastructure
    & Deploy-Module.ps1 -Module k8s

• If you have a domain somewhere, point it to the load balancer IP to reach the ingress controller. You can use LetsEncrypt for https and maybe external dns to automate the creation of dns entries. If you don't, follow the next steps:

    # Import the self signed trusted root certificate to enable https.
    # A tls certificate signed by this root CA was created by the k8s module and uploaded as a secret to the 
    # created kubernetes namespaces
    # You can now create ingress resources within these namespaces and reference the secret for https
    # Requires elevated permissions
    & terraform-modules/k8s/Import-RootCA.ps1

    # Create dns entries in the hosts file of your local machine
    # Requires elevated permissions
    # This will add ${SubDomain}.${top_level_domain} to the hosts file
    & terraform-modules/k8s/Add-DnsEntries.ps1 -SubDomains sample,dev1,dev2

    # Deploy a sample ingress app to verify that ingress/https is working
    # Browse to https://sample.${top_level_domain} afterwards
    # This requires a dns entry to be available
    & kubectl apply -f "./outputs/sample-ingress-app.yaml"

• (Optional) deploy the azure-pinger module to generate traffic and prevent the instances in oci from going idle

    # Requires an azure account and the az cli to be installed
    # the script will authenticate interactively with "az login"
    & Deploy-Module.ps1 -Module azure-pinger