CKAD

CKAD

Pods

Configuration

Folders

installation
|
-- docker - docker files for containers used in this exercise
-- multi - multi machine vagrant setup with K8S provisioned
-- plain - multi machine vagrant setup - plain ubuntu
-- provision - provisioning scripts
k8s
|
-- deploymet
-- pod
spring-boot-demo - spring boot demo app, java project

Build demo app

cd spring-boot-demo
./mvnw package

JAR file is in target folder.

Create K8s Cluster

Create the cluster with multipass

Default settings are 1G of memory and 1 CPU. CPU is enough, but feels faster if the memory is slightly increased. Creating three machines, one control plane and two worker nodes.

multipass launch --mem 3G -n control-node
multipass launch --mem 3G -n worker-1
multipass launch --mem 3G -n worker-2

Once they are up and running you can connect to the shell and install microk8s

multipass shell control-node
sudo snap install microk8s --classic
sudo microk8s enable dns dashboard storage

When microk8s is up and running worker nodes can join the cluster. On the control node issue command

sudo microk8s add-node
From the node you wish to join to this cluster, run the following:
microk8s join 10.27.179.152:25000/1b7934b93d394efa5fa71c0c2b28c4ad/65265a586ee8

If the node you are adding is not reachable through the default interface you can use one of the following:
microk8s join 10.27.179.152:25000/1b7934b93d394efa5fa71c0c2b28c4ad/65265a586ee8

Copy paste the join command and excute on the worker node. You need to do this for every node (microk8s add-node).

Verify the result

~$ kubectl get nodes
NAME           STATUS   ROLES    AGE   VERSION
worker-2       Ready    <none>   35m   v1.22.4-3+adc4115d990346
control-node   Ready    <none>   48m   v1.22.4-3+adc4115d990346
worker-1       Ready    <none>   37m   v1.22.4-3+adc4115d990346

If you want to stop all the machines

multipass stop --all

Get rid of all of them

multipass delete --all
multipass purge

Interesting pages

Distroless https://github.com/GoogleContainerTools/distroless

https://github.com/netlify/gotrue

https://github.com/bradtraversy/vanillawebprojects

https://github.com/bradtraversy/50projects50days

https://github.com/google/zx

https://github.com/dgkanatsios/CKAD-exercises/blob/master/a.core_concepts.md

https://github.com/bmuschko/ckad-study-guide