This guide explains how to deploy a MicroK8s cluster and add it as a second cloud on your Juju controller, so that you can deploy Kubernetes workloads.
Requirements
- An existing bootstrapped Juju controller on a cloud like AWS, Azure, OpenStack, LXD, etc
Steps
Deploy Cluster
Create a new model microk8s and deploy a 3-node cluster:
juju add-model microk8s
juju deploy microk8s -n 3 --config hostpath_storage=true --constraints 'mem=4G root-disk=20G'
Then, make sure to expose the microk8s application so that the Juju controller can reach the Kubernetes cluster:
juju expose microk8s
Wait until the cluster is deployed. The juju status should look like this:
Model Controller Cloud/Region Version SLA Timestamp
microk8s zs zerostack/KHY 2.9.38 unsupported 01:41:13+03:00
App Version Status Scale Charm Channel Rev Exposed Message
microk8s active 3 microk8s 77 yes node is ready
Unit Workload Agent Machine Public address Ports Message
microk8s/30 active idle 0 172.16.100.226 16443/tcp node is ready
microk8s/31* active idle 1 172.16.100.18 16443/tcp node is ready
microk8s/33 active idle 2 172.16.100.111 16443/tcp node is ready
Machine State Address Inst id Series AZ Message
0 started 172.16.100.226 795b9667-fd5d-4ff4-8c42-e2de40e581c5 focal nova ACTIVE
1 started 172.16.100.18 27a00794-d77d-4aae-ab9c-18032e293085 focal nova ACTIVE
2 started 172.16.100.111 584ad91e-5ae7-4e1a-9a2c-6a4cc24d8ee2 focal nova ACTIVE
Add Kubernetes cluster as a cloud on the Juju controller
Retrieve the kubeconfig for the cluster with the following command:
# Juju 2.9
kubeconfig="$(juju run --unit microk8s/leader -- microk8s config)"
# Juju 3.1
kubeconfig="$(juju exec --unit microk8s/leader -- microk8s config)"
Then, create a microk8s-cloud cloud on your Juju controller with:
controller="$(juju controller-config controller-name)"
echo "$kubeconfig" | juju add-k8s microk8s-cloud --controller "$controller"
If successful, you should see output like the following:
k8s substrate "microk8s/localhost" added as cloud "microk8s-cloud" on controller zs.
Finally, check the configured clouds on the controller using juju clouds. The output should look like this:
Clouds available on the controller:
Cloud Regions Default Type
microk8s-cloud 1 localhost k8s
zerostack 1 KHY openstack
Deploy Kubernetes charms
Now that the Juju controller is aware of our cluster, we can deploy Kubernetes workloads like this:
Create a model prometheus using the microk8s-cloud cloud.
juju add-model prometheus microk8s-cloud
Then, deploy prometheus-k8s:
juju deploy prometheus-k8s
Watch the progress of the deployment with juju status. After a while, it should look like this:
Model Controller Cloud/Region Version SLA Timestamp
prometheus zs microk8s-cloud/localhost 2.9.38 unsupported 01:57:38+03:00
App Version Status Scale Charm Channel Rev Address Exposed Message
prometheus 2.44.0 active 1 prometheus-k8s edge 130 10.152.183.86 no
Unit Workload Agent Address Ports Message
prometheus/0* active idle 10.1.5.148