Add a host to the cluster

That was pretty easy, let's add another host to this cluster by running the agent.

To add the host as an agent to the cluster, we need two things:

• The IP address or DNS name of the server (in this case, the IP address of the host with hostname master)
• A cluster secret to join the cluster (in this case, pre-configured for demo purposes)

Run the following command on node01 to add the host to the cluster:

curl -sfL https://get.k3s.io | K3S_CLUSTER_SECRET=thisisverysecret K3S_URL=https://[[HOST_IP]]:6443 sh -

Wait for node1 to become Ready in the cluster by retrieving the nodes in the cluster:

k3s kubectl get node

For your convenience, the following command will wait until the node shows up as Ready:

until k3s kubectl get node | grep node01 | grep -q ' Ready'; do sleep 1; done; k3s kubectl get node

Create and access workload

Now we are ready to deploy a workload and access it. The first host has a template file at /root/rancher-demo.yaml.tpl which we can use to deploy a web page showing the amount of pods running for a Deployment.

cat /root/rancher-demo.yaml.tpl | sed 's/__HOSTNAME__/[[HOST_SUBDOMAIN]]-80-[[KATACODA_HOST]].environments.katacoda.com/g' | k3s kubectl create -f -

Wait for the pods to be running:

k3s kubectl rollout status deploy/rancher-demo

Now you can access the created workload by clicking on the following link:

https://[[HOST_SUBDOMAIN]]-80-[[KATACODA_HOST]].environments.katacoda.com/

After checking it out, scale the deployment to more replicas and see the result:

k3s kubectl scale deploy/rancher-demo --replicas=5