Adjust VMs worker nodes

Got it! You'll be setting up the cluster with:

• Physical Machine 1: VM1 (Master Node) and VM2 (Worker Node)
• Physical Machine 2: VM3 (Worker Node)

Here’s a revised and detailed setup guide for your Kubernetes cluster using k3s, Alpine Linux, and the specified configuration.

Cluster Topology

Step-by-Step Configuration

1. Network Configuration

General Settings

• Ensure all VMs have a private network interface (e.g., eth1) for cluster communication. You can use a shared physical network or a virtual network setup on your hypervisor (e.g., VirtualBox, Proxmox, etc.).
• Assign static IP addresses to all VMs for consistency. For example:
  • VM1 (Master): 192.168.100.10
  • VM2 (Worker): 192.168.100.11
  • VM3 (Worker): 192.168.100.12

Disable IPv6

Run the following commands on all VMs to disable IPv6:

echo "net.ipv6.conf.all.disable_ipv6 = 1" >> /etc/sysctl.conf
sysctl -p

2. Install Alpine Linux

Install Alpine Linux 3.18 or later on all VMs. During installation:

• Select minimal installation for a lightweight setup.
• Ensure the VMs have access to the internet for package updates.

3. Install Docker/Containerd

k3s relies on containerd as the container runtime. Install and configure containerd on all VMs:

apk update && apk add containerd

Enable and start containerd:

systemctl enable containerd && systemctl start containerd

4. Install k3s

Master Node (VM1)

Install and initialize the k3s cluster on the master node:

curl -sfL https://get.k3s.io | sh -

After installation, the cluster is running, and you can access it using kubectl:

kubectl get nodes

The output should show VM1 as the master node:

NAME     STATUS   ROLES           AGE   VERSION
vm1      Ready    control-plane   5s    v1.25.4+k3s5

Worker Nodes (VM2 and VM3)

On both worker nodes (VM2 and VM3), install k3s and join them to the cluster. Replace <MASTER-IP> with the master node's IP (192.168.100.10) and <JOIN-TOKEN> with the token from the master node (found in /var/lib/rancher/k3s/server/node-token):

curl -sfL https://get.k3s.io | K3S_URL=https://<MASTER-IP>:6443 K3S_TOKEN=<JOIN-TOKEN> sh -

Verify that all nodes are connected:

kubectl get nodes

The output should show all three nodes:

NAME     STATUS   ROLES           AGE   VERSION
vm1      Ready    control-plane   10m   v1.25.4+k3s5
vm2      Ready    <none>          2m    v1.25.4+k3s5
vm3      Ready    <none>          1m    v1.25.4+k3s5

5. NFS Storage Configuration

You mentioned using an existing NFS server on Physical Machine 1. Here’s how to integrate it into your Kubernetes cluster:

Mount NFS Share on Master Node (VM1)

Mount the NFS share on the master node. For example:

mount -t nfs <NFS-SERVER-IP>:/path/to/export /mnt/nfs

Create a PersistentVolume (PV)

Create a pv-nfs.yaml file:

apiVersion: v1
kind: PersistentVolume
metadata:
  name: nfs-pv
spec:
  storageClassName: manual
  capacity:
    storage: 100Gi
  accessModes:
    - ReadWriteMany
  nfs:
    server: <NFS-SERVER-IP>
    path: /path/to/export

Apply the PV:

kubectl apply -f pv-nfs.yaml

Create a PersistentVolumeClaim (PVC)

Create a pvc-nfs.yaml file:

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: nfs-pvc
spec:
  storageClassName: manual
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 50Gi

Apply the PVC:

kubectl apply -f pvc-nfs.yaml

Now, any application deployed in the cluster can use this PVC for persistent storage.

6. Application Deployment

You can now deploy applications like Nextcloud, Vaultwarden, Paperless-ngx, Bookstack, and others. Here are some examples:

Nextcloud Deployment (Example)

Create a manifest file (nextcloud.yaml):

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nextcloud
spec:
  replicas: 1
  selector:
    matchLabels:
      app: nextcloud
  template:
    metadata:
      labels:
        app: nextcloud
    spec:
      containers:
        - name: nextcloud
          image: nextcloud:23
          ports:
            - containerPort: 80
          volumeMounts:
            - mountPath: /var/www/html
              name: nextcloud-storage
      volumes:
        - name: nextcloud-storage
          persistentVolumeClaim:
            claimName: nfs-pvc

Apply the deployment:

kubectl apply -f nextcloud.yaml

7. Optional Enhancements

Monitoring

Install Prometheus and Grafana for monitoring:

helm repo add prometheus-community https://prometheus-community.github.io/helm-charts
helm repo update
helm install prometheus prometheus-community/prometheus
helm install grafana grafana/grafana

Dashboard Access

Access the k3s dashboard:

k3s kubectl proxy

Visit http://localhost:8001/api/v1/namespaces/kubernetes-dashboard/services/https:kubernetes-dashboard:/proxy/ in your browser.

Ingress Controller (Optional)

Install Nginx Ingress for exposing applications:

helm repo add ingress-nginx https://kubernetes.github.io/ingress-nginx
helm repo update
helm install ingress-ingress-nginx/ingress-nginx

8. Final Notes

• Ensure your VMs have proper firewall rules (e.g., allow traffic on port 6443, 30000-32767).
• Use a reverse proxy (e.g., Nginx) with TLS to expose your applications securely.
• Consider setting up backups for your Kubernetes cluster using tools like Velero.

If you need help with specific application deployments or additional configurations, let me know!