Kubernetes is the most trending word in the sphere of Containerization and Microservices. But deploying Kubernetes can be expensive, mostly when not being done to power production applications. In this tutorial, I’ll introduce you to MicroK8s tool which enables you to run the latest stable upstream Kubernetes release in Snap.
Production deployment: Deploy Production Kubernetes Cluster with Ansible & Kubespray
For Docker users: How To run Local Kubernetes clusters in Docker
MicroK8s is just a single package of k8s that installs on most Linux flavors and any other system which can run Snap. This is fit for running on IoT devices such as Raspberry Pi, personal computers and Desktops.
This deployment is not recommended for Production setups but only for offline development, prototyping, testing, or use it on a VM as a small, cheap, reliable k8s for CI/CD.
Features of MicroK8s – (https://microk8s.io/)
- Fast install – Get a full Kubernetes system running in under 60 seconds.
- Small – Use MicroK8s in your CI/CD pipelines and get on with your day without headaches.
- Secure – Runs safely on your laptop with state of the art isolation.
- Complete – Includes a docker registry so you can make containers, push them, and deploy them all on your laptop.
- Upgrades – When a new major version comes out, upgrade with a single command (or automatically).
- Featureful – Cool things you probably want to try on a small, standard K8s are all built-in. Just enable them and go.
- GPU Passthrough – Give MicroK8s a GPGPU and your Docker containers can get all nice and CUDA.
- Upstream – CNCF binaries delivered to your laptop, with updates and upgrades.
- Linux Operating system – Debian, Ubuntu, CentOS, RHEL, Fedora, Arch e.t.c
- Snap installed
- User with sudo
Step 1: Install Snapd
We have guides on installation of Snapd:
Step 2: Install MicroK8s
After installing Snap, you can start MicroK8s installation using Snap. Snaps are frequently updated to match each release of Kubernetes.
sudo snap install microk8s --classic
Installation should look like this:
All Published version can be checked with:
snap info microk8s
Once MicroK8s is installed, it will start creating a one node Kubernetes cluster. Status for this deployment can be checked using.
# microk8s.status microk8s is running addons: jaeger: disabled fluentd: disabled gpu: disabled storage: disabled registry: disabled ingress: disabled dns: disabled metrics-server: disabled prometheus: disabled istio: disabled dashboard: disabled
From the output, we can see is MicroK8s is running and the state of addons available.
To check cluster info, use:
# microk8s.kubectl cluster-info Kubernetes master is running at https://127.0.0.1:16443
Also get status of k8s node.
# microk8s.kubectl get nodes NAME STATUS ROLES AGE VERSION microk8s Ready 5m17s v1.14.0
If you’re not comfortable with
microk8s.kubectl command, you can create an alias for it.
echo "alias kubectl='microk8s.kubectl'" >>~/.bashrc source ~/.bashrc
Then you can use
# kubectl get nodes -o wide NAME STATUS ROLES AGE VERSION INTERNAL-IP EXTERNAL-IP OS-IMAGE KERNEL-VERSION CONTAINER-RUNTIME microk8s Ready
10m v1.14.0 192.168.10.175 Ubuntu 18.04.2 LTS 4.15.0-45-generic containerd://1.2.5
Enable/Disable Kubernetes Addons on MicroK8s
Addons available for MicroK8s are:
- dashboard: Deploy kubernetes dashboard as well as grafana and influxdb.
- dns: Deploy kube dns
- storage: Create a default storage class. This storage class makes use of the hostpath-provisioner pointing to a directory on the host. Persistent volumes are created under $SNAP_COMMON/default-storage.
- ingress: Create an ingress controller.
- istio: Deploy the core Istio services. Use the
microk8s.istioctlcommand to manage your deployments.
- registry: Deploy an image private registry and expose it on
- metrics-server: Deploy the Metrics Server.
- prometheus: Deploy the Prometheus Operator v0.25.
- fluentd: Deploy Elasticsearch-Kibana-Fluentd logging and monitoring solution.
- jaeger: Deploy the Jaeger Operator v1.8.2 in the “simplest” configuration.
You can enable and disable addons available for Kubernetes.
microk8s.enable command to enable addons.
# microk8s.enable dashboard dns Enabling dashboard secret/kubernetes-dashboard-certs created serviceaccount/kubernetes-dashboard created deployment.apps/kubernetes-dashboard created service/kubernetes-dashboard created service/monitoring-grafana created service/monitoring-influxdb created service/heapster created deployment.extensions/monitoring-influxdb-grafana-v4 created serviceaccount/heapster created configmap/heapster-config created configmap/eventer-config created deployment.extensions/heapster-v1.5.2 created dashboard enabled Enabling DNS Applying manifest service/kube-dns created serviceaccount/kube-dns created configmap/kube-dns created deployment.extensions/kube-dns created Restarting kubelet DNS is enabled
Enable Storage addon:
# microk8s.enable storage Enabling default storage class deployment.extensions/hostpath-provisioner created storageclass.storage.k8s.io/microk8s-hostpath created Storage will be available soon
To enable Storage and Istio addons:
# microk8s.enable istio
The same format apply for other plugins. Confirm enabled addons with:
# microk8s.status microk8s is running addons: jaeger: disabled fluentd: disabled gpu: disabled storage: enabled registry: enabled ingress: disabled dns: disabled metrics-server: disabled prometheus: disabled istio: disabled dashboard: enabled
For more information like URL, use:
microk8s.disable command to disable addon.
# microk8s.disable istio Disabling Istio namespace "istio-system" deleted Istio is terminating
Deploying Pods and Containers on MicroK8s
Deployments are done in standard Kubernetes way. See the example below which will create Nginx deployment with two containers.
# microk8s.kubectl run nginx --replicas 2 --image nginx deployment.apps/nginx created # microk8s.kubectl get deployments NAME READY UP-TO-DATE AVAILABLE AGE nginx 2/2 2 2 39s # microk8s.kubectl get pods NAME READY STATUS RESTARTS AGE nginx-7db9fccd9b-7662b 1/1 Running 0 61s nginx-7db9fccd9b-87z6d 1/1 Running 0 61s
# microk8s.kubectl expose deployment nginx --port 80 --target-port 80 \ --type ClusterIP --selector=run=nginx --name nginx service/nginx exposed # microk8s.kubectl get services NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE kubernetes ClusterIP 10.152.183.1 443/TCP 27m nginx ClusterIP 10.152.183.54 80/TCP 104s
# microk8s.kubectl delete deployment nginx deployment.extensions "nginx" deleted # microk8s.kubectl delete service nginx service "nginx" deleted
Stopping and Restarting MicroK8s
You can easily shutdown MicroK8s when not in use without un-installing it.
# microk8s.stop Stopped.
Start MicroK8s using:
# microk8s.start Started.
If you wish to completely remove MicroK8s, first stop all running pods.
Then remove MicroK8s snap.
snap remove microk8s
MicroK8s is the quickest and most lightweight Kubernetes deployment tool available. It is ideal for playing with Kubernetes without mastery of Linux and Containers concepts before you can get started. For more reading, visit MicroK8s Documentation page.