Kubernetes testing configuration

This repository contains configuration which I'm using to create a bare metal kubernetes cluster. With this configuration I'm getting to learn the ins and outs of kubernetes.

Kubernetes so far is a complex beast compared to a simple standalone docker-compose configuration. There are lots of new concepts and documenting those are outside the scope of this project.

This project isjust for fun and learning. If you're looking for a tutorial, look elsewhere.

Cluster configuration

Vagrant

When vagrant is installed, the cluster can be easily configured with the

vagrant up

in the root of this project. It'll spin up an Ubuntu 18.04 virtualbox machine and will automatically install kubernetes. Also, a network policy provider (not sure if it's called like this, but I believe so) called calico is automatically installed. This is a vital piece of the kubernetes cluster.

Network setup

In the Vagrantfile a host local network is configured. The master node will get IP address 192.168.34.10.

Kubernetes pods will get an IP address in 10.45.0.0/16. The services get an IP address from 10.44.0.0/16. A local route (from outside the VM) can be added to 10.44.0.0/15 -> 192.168.34.10 to be able to reach all pods and services from the local host.

calicoctl

This is a utility to access and modify the calico configuration. You'll need a bunch of environment vars to be able to use it as root:

export ETCD_ENDPOINTS=https://localhost:2379
export ETCD_CA_CERT_FILE=/etc/kubernetes/pki/etcd/ca.crt
export ETCD_CERT_FILE=/etc/kubernetes/pki/etcd/server.crt
export ETCD_KEY_FILE=/etc/kubernetes/pki/etcd/server.key

Test configurations

Traefik

Traefik is my goto proxy for my development setups. So far I've only used it with docker as a configuration provider. As it also supports kubernetes as an ingress controller and loadbalancer, I figured I should figure this out as well. In the traefik subdirectory the deployment configuration can be found.

The configuration is based on the traefik kubernetes guide with letsencrypt, but without the letsencrypt part (which I currently find irrelevant).

Cron job

Kubernetes supports cron jobs to be run in a cluster. A sample configuration can be found here