Always free k3s

This file provides some commands for you to copy and paste

Values you need to change will be in < > brackets, e.g.:

ssh ubuntu@<MASTER_NODE_IP_ADDRESS> -i <PATH_TO_KEY_FILE>

translates to

ssh ubuntu@1.2.3.4 -i ssh-key-2023-09-01.key

Cluster setup

SSHing into VMs

ssh ubuntu@<MASTER_NODE_IP_ADDRESS> -i <PATH_TO_KEY_FILE>

Clearing iptables

## save existing rules
sudo iptables-save > ~/iptables-rules
## modify rules, remove drop and reject lines
grep -v "DROP" iptables-rules > tmpfile && mv tmpfile iptables-rules-mod
grep -v "REJECT" iptables-rules-mod > tmpfile && mv tmpfile iptables-rules-mod
## apply the modifications
sudo iptables-restore < ~/iptables-rules-mod
## check
sudo iptables -L
## save the changes
sudo netfilter-persistent save
sudo systemctl restart iptables

Installing k3s on your machine

curl -sLS https://get.k3sup.dev | sh
sudo install k3sup /usr/local/bin/

## Verify installation
k3sup --help

Setting up the master

If you want to merge it with your existing kubeconfig

k3sup install \
--host <MASTER_NODE_IP_ADDRESS> \
--user ubuntu \
--ssh-key <PATH_TO_KEY_FILE> \
--context k3s-on-oracle \
--local-path $HOME/.kube/config \
--merge

If you have no existing kubeconfig:

k3sup install \
--host <MASTER_NODE_IP_ADDRESS> \
--user ubuntu \
--ssh-key <PATH_TO_KEY_FILE> \
--context k3s-on-oracle \

Joining agents

k3sup join \
  --ip <AGENT_NODE_IP_ADDRESS> \
  --server-ip <MASTER_NODE_IP_ADDRESS> \
  --user ubuntu \
  --ssh-key <PATH_TO_KEY_FILE>

Configuring the cluster

Installing ArgoCD

Install to cluster

kubectl create namespace argocd
kubectl apply -n argocd -f https://raw.githubusercontent.com/argoproj/argo-cd/stable/manifests/install.yaml

Get admin password

kubectl get secret argocd-initial-admin-secret -n argocd -o jsonpath='{.data.password}' | base64 --decode

Port forward

kubectl port-forward svc/argocd-server -n argocd 8080:80

Deploying the first app

SSH-key generation

ssh-keygen -t rsa -b 4096 -f github-deploy-key

Helm chart creation

helm create whoami

Annotations to add to ingress

annotations:
  kubernetes.io/ingress.class: traefik
  traefik.ingress.kubernetes.io/router.middlewares: whoami-strip-prefix@kubernetescrd

Strip-prefix middleware

Simply paste this into the ingress.yaml at the bottom. IMPORTANT: Keep the ---!

---
apiVersion: traefik.containo.us/v1alpha1
kind: Middleware
metadata:
  name: strip-prefix
spec:
  stripPrefix:
    prefixes:
      - /whoami

Installing cert-manager

helm install \
  cert-manager jetstack/cert-manager \
  --namespace cert-manager \
  --create-namespace \
  --version v1.12.0 \
  --set installCRDs=true

Installing the ionos-webhook for cert manager

helm repo add cert-manager-webhook-ionos https://fabmade.github.io/cert-manager-webhook-ionos

helm install cert-manager-webhook-ionos cert-manager-webhook-ionos/cert-manager-webhook-ionos -ncert-manager

Set Argo to insecure

Edit the configmap

kubectl edit configmap argocd-cmd-params-cm -n argocd

Add the following lines at the same level as kind and metadata

apiVersion: v1
data:
  server.insecure: "true"
kind: ConfigMap

Restart the deployment:

kubectl -n argocd rollout restart deploy

Let's get stuff deployed

Installing postgres

You can choose any <RELEASE_NAME> you like, e.g. my-postgres

helm install <RELEASE_NAME> \
  oci://registry-1.docker.io/bitnamicharts/postgresql \
  -n bitnami-postgres \
  --create-namespace \
  --set auth.postgresPassword=<PASSWORD_FOR_POSTGRES_USER>

Posting to url shortener service

curl --location 'https://<YOUR_DOMAIN>/shortme/shorten' \
--header 'Content-Type: application/x-www-form-urlencoded' \
--data-urlencode 'original_url=https://www.google.com'