Deploying EMQ X Edge on Raspberry Pi Using K3S

K3S is a light-weight Kubernetes environment, this article shows you how to deploy EMQ X Edge on Raspberry Pi using K3S.

EMQ X Edge is a light-weight edge computing message middleware for Internet of Things, which supports deployment of edge hardware in a resource-constrained environment.

Environment

It is required that the Raspberry Pi can visit the internet to install EMQ X Edge using K3S. Here we will using three Raspberry Pis to demonstrate our deployment.

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|Host Name   | IP Address    | Role   |
=======================================
|raspberrypi | 192.168.1.99  | server |
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|emqx1       | 192.168.1.100 | agent  |
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|emqx2       | 192.168.1.101 | agent  |
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Preparation

Download K3S

Currently K3S supports x86_64, armhf and arm64. For the Raspberry Pi, the one for armhf should be installed.

$ wget https://github.com/rancher/k3s/releases/download/v0.2.0/k3s-armhf
$ mv k3s-armhf /usr/local/bin/k3s
$ chmod +x /usr/local/bin/k3s

Start the server

$ sudo k3s server

Create a cluster for K3S

Open the /var/lib/rancher/k3s/server/node-token file on server node to get node token .

$ NODE_TOKEN=$(sudo cat /var/lib/rancher/k3s/server/node-token)

On the agent node, run following command to join the K3S cluster:

$ sudo k3s agent --server https://192.168.1.99:6443 --token ${NODE_TOKEN}

Use kubectl to manage K3S cluster from remote (optional)

Any device which can connect to K3S cluster we created above can manage this cluster using kubectl by doing following:

• Install the kubectl on the managing device
• Copy the /etc/rancher/k3s/k3s.yaml to the managing device in file ~/.kube/config
• Modify ~/.kube/config , change https://localhost:6443 tohttps://192.168.1.99:6443
• Manage the K3S cluster using kubectl

$ kubectl get nodes
NAME         STATUS  ROLES  AGE  VERSION
emqx2        Ready   <none>  29m  v1.13.4-k3s.1
emqx1         Ready   <none>  29m  v1.13.4-k3s.1
raspberrypi Ready   <none>  31m   v1.13.4-k3s.1

Install Helm

Install Helm client

Download and unzip Helm release form https://github.com/kubernetes/helm/releases and copy it to /usr/local/bin/helm .

Install Tiller server

Create a Service Account for Tiller.

$ kubectl create serviceaccount tiller --namespace kube-system

Grant cluster-admin privilege to tiller:

Add the tiller to the cluster-admin role by appending following to rbac-config.yaml file:

$ cat <<EOF >rbac-config.yaml
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRoleBinding
metadata:
name: tiller
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: cluster-admin
subjects:
- kind: ServiceAccount
name: tiller
namespace: kube-system
EOF

Run kubectl create -f to give tiller the privilege of cluster-admin:

$ kubectl create -f rbac-config.yaml

Install Tiller server

$ helm init --service-account tiller

Verify the installation

After the installation you can check it with the following command:

$ helm version

If it shows the correct Helm client and the Tiller server version, it means the installation is successful.

Or you can use kubectl to check it:

$ kubectl get pods -n kube-system

Deploying the EMQ X Cluster

Deploy EMQ X using Helm

$ git clone https://github.com/emqx/emqx-chart $ cd emqx-chart $ helm install --name myemqx --set deployment.image="emqx/emqx-edge:latest" .

Check the state of EMQ X cluster

check the pods list.

$ kubectl get pods |grep myemqx myemqx-emqx-chart-54974fc5f5-v8chq           1/1     Running   0          2m9s myemqx-emqx-chart-54974fc5f5-zz9gc           1/1     Running   0          2m9s

Check the EMQ X cluster state.

$ kubectl exec myemqx-emqx-chart-54974fc5f5-v8chq /opt/emqx/bin/emqx_ctl cluster status 
Cluster status: [{running_nodes,['emqx@10.42.2.11','emqx@10.42.1.15']}]

Welcome to our open source project github.com/emqx/emqx. Please visit the documentation for details.