This document contains the commands used in the kubernetes in 10 minutes presentation. Feel free to let me know if you have improvments or catch any typos.
Allocate 3 VMs on your favorite cloud hosting provider.
Install k3sup
curl -sLS https://get.k3sup.dev | sh
sudo install k3sup /usr/local/bin/Use k3sup to install k3s on master node
export IP=xxx.yyy.zzz.199
k3sup install --ip $IP
mv kubeconfig ~/.kube/config
kubectl get nodes
NAME STATUS ROLES AGE VERSION
debian-2gb-nbg1-1 Ready worker 4m47s v1.14.6-k3s.1Use k3sup to join work nodes
k3sup join --ip xxx.yyy.zzz.200 --server-ip $IP
k3sup join --ip xxx.yyy.zzz.201 --server-ip $IPCheck that the nodes are joining
kubectl get nodes
NAME STATUS ROLES AGE VERSION
debian-2gb-nbg1-1 Ready worker 4m47s v1.14.6-k3s.1
debian-2gb-nbg1-2 Ready worker 5m29s v1.14.6-k3s.1
debian-2gb-nbg1-3 Ready master 8m25s v1.14.6-k3s.1Check out pods (none yet)
kubectl get pods
No resources found.Lets build our applications. This is automated, so not much to do here.
If you are interested in the applications things to noice are:
- java applications build on quarkus with graalvm for startup times and memory usage.
- multi-stage docker builds, so no need for local java tools in the builds.
- secret is not part of repository. Copy secret.env.example to secret.env and insert your twitter account details.
- static yaml files in deploy documents our deployments
- a git post-update hook updates the image tag version in the deployment yaml files
- drone builds the images
- flux monitors and deploy them
kubectl apply -f namespaces
kubectl config set-context --current --namespace=apps
kubectl create secret generic wisdom-service-secret --from-env-file=secret.env
kubectl apply -f wisdom-service/deploy
kubectl apply -f wisdom-frontend/deploy
kubectl get pods
NAME READY STATUS RESTARTS AGE
wisdom-frontend-6c86667dd-pmnsw 1/1 Running 0 2m59s
wisdom-frontend-6c86667dd-thjlc 1/1 Running 0 3m5s
wisdom-service-6c748d8748-5d87t 1/1 Running 0 3m6s
wisdom-service-6c748d8748-v5r9k 1/1 Running 0 2m58sAdd wisdom.mejlholm.org to /etc/hosts (or setup real dns)
sudo nano /etc/hosts #add the following line
xxx.yyy.zzz.199 wisdom.mejlholm.orgLets test our application
curl http://wisdom.mejlholm.org/wisdom/random
{"message":"\"Debuggers don't remove bugs. They only show them in slow motion.\" - Unknown"}And check it out in the browser: http://wisdom.mejlholm.org/
Sometimes you get a better overview with a ui - kubernetes web ui comes to the rescue.
kubectl apply -f kubernetes-web-ui.yaml
kubectl proxy
kubectl -n kube-system describe secret $(kubectl -n kube-system get secret | grep admin-user | awk '{print $1}')
kubectl delete -f kubernetes-web-ui.yamlAs a bonus we'll use the FluxCD operator to handle our deployments. What we commit to git will be deployed automatically for us.
export FLUX_FORWARD_NAMESPACE=flux
kubectl create ns flux
fluxctl install \
--git-user=mejlholm \
[email protected] \
[email protected]:Cloud-Native-Aalborg/Meetup-1 \
--git-paths=namespaces,wisdom-frontend/deploy,wisdom-service/deploy \
--namespace=flux | kubectl apply -f -
kubectl patch deployments -n flux flux --type='json' -p='[{"op": "add", "path": "/spec/template/spec/containers/0/args/-", "value": "--git-ci-skip"}]'
fluxctl identity --k8s-fwd-ns flux
# Manually add key to Deploy keys in GitHub settings.
K3s is not HA ready yet - but it makes a great little tool for testing kubernetes (and it runs a raspberry pi). K3s has an open port for the api by default, please check if running anything in the public cloud.
Below you find links to the things we've used in this demo:
Arne Mejlholm, Java developer at Spar Nord. Driving the adoptation of docker/kubernetes and a lot more in the IT development department. Passionated about devops to improve and learn.
- Arne Mejlholm [email protected]
- Twitter @mejlholm34263