# Kubernetes Cluster Setup

Before deploying Akri, you must have a Kubernetes cluster (v1.16 or higher) running with `kubectl` and `Helm` installed. Akri is Kubernetes native, so it should run on most Kubernetes distributions. This document provides cluster setup instructions for the three Kubernetes distributions that all of our end-to-end tests run on.

{% hint style="info" %}
Note: All nodes must be Linux on amd64, arm64v8, or arm32v7.
{% endhint %}

## Install Kubernetes Distribution

{% tabs %}
{% tab title="Kubernetes" %}

1. Reference [Kubernetes documentation](https://kubernetes.io/docs/tasks/tools/) for instructions on how to install Kubernetes. See Akri's [release notes](https://github.com/project-akri/akri/releases) to see what versions of Kubernetes Akri has been tested on.
2. Install Helm for deploying Akri.

   ```bash
    sudo apt install -y curl
    curl -L https://raw.githubusercontent.com/helm/helm/master/scripts/get-helm-3 | bash
   ```

{% hint style="info" %}
Note: To enable workloads on a single-node cluster, remove the master taint.

```bash
kubectl taint nodes --all node-role.kubernetes.io/master-
```

{% endhint %}
{% endtab %}

{% tab title="K3s" %}

1. Install [K3s](https://k3s.io/). The following will install the latest K3s version. Reference Akri's [release notes](https://github.com/project-akri/akri/releases) to see what versions of K3s Akri has been tested on.

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

   > Note: Optionally specify a version with the `INSTALL_K3S_VERSION` env var as follows: `curl -sfL https://get.k3s.io | INSTALL_K3S_VERSION=v1.21.5+k3s1 sh -`
2. Grant admin privilege to access kube config.

   ```bash
    sudo addgroup k3s-admin
    sudo adduser $USER k3s-admin
    sudo usermod -a -G k3s-admin $USER
    sudo chgrp k3s-admin /etc/rancher/k3s/k3s.yaml
    sudo chmod g+r /etc/rancher/k3s/k3s.yaml
    su - $USER
   ```
3. Check K3s status.

   ```bash
    kubectl get node
   ```
4. Install Helm.

   ```bash
    export KUBECONFIG=/etc/rancher/k3s/k3s.yaml
    sudo apt install -y curl
    curl -L https://raw.githubusercontent.com/helm/helm/master/scripts/get-helm-3 | bash
   ```
5. If desired, add nodes to your cluster by running the K3s installation script with the `K3S_URL` and `K3S_TOKEN` environment variables. See [K3s installation documentation](https://rancher.com/docs/k3s/latest/en/quick-start/#install-script) for more details.
   {% endtab %}

{% tab title="MicroK8s" %}

1. Install [MicroK8s](https://microk8s.io/docs). The following will install the latest MicroK8s version. Add `--channel=$VERSION/stable` to specify as specific Kubernetes version. Reference Akri's [release notes](https://github.com/project-akri/akri/releases) to see what versions of MicroK8s Akri has been tested on.

   ```bash
    snap install microk8s --classic
   ```
2. Grant admin privilege for running MicroK8s commands.

   ```bash
    sudo usermod -a -G microk8s $USER
    sudo chown -f -R $USER ~/.kube
    su - $USER
   ```
3. Check MicroK8s status.

   ```bash
    microk8s status --wait-ready
   ```
4. Enable CoreDNS, Helm and RBAC for MicroK8s.

   ```bash
    microk8s enable dns helm3 rbac
   ```
5. If you don't have an existing `kubectl` and `helm` installations, add aliases. If you do not want to set an alias, add `microk8s` in front of all `kubectl` and `helm` commands.

   ```bash
    alias kubectl='microk8s kubectl'
    alias helm='microk8s helm3'
   ```
6. By default, MicroK8s does not allow Pods to run in a privileged context. None of Akri's components run privileged; however, if your custom broker Pods do in order to access devices for example, enable privileged Pods like so:

   ```bash
    echo "--allow-privileged=true" >> /var/snap/microk8s/current/args/kube-apiserver
    microk8s.stop
    microk8s.start
   ```
7. If desired, reference [MicroK8's documentation](https://microk8s.io/docs/clustering) to add additional nodes to the cluster.
   {% endtab %}
   {% endtabs %}