Introduction to Containers Demo

demo.md

Links for Demo

Docker playground: https://labs.play-with-docker.com/

Kubernetes playground: https://labs.play-with-k8s.com/

Kubernetes Cheat Sheet: https://kubernetes.io/docs/reference/kubectl/cheatsheet/

Introduction

hostname
unshare -u bash
hostname testhost
hostname
exit
hostname

Docker

Exercise 1:

docker pull httpd:latest
docker save httpd:latest -o httpd.tar
mkdir httpd && tar -C httpd -xvf httpd.tar && cd httpd
ls
jq . manifest.json
jq . <config.json>
cd ./<path to a layer dir>
mkdir layer && tar -C layer -xvf layer.tar
ls -la layer

Exercise 2:

docker run -d -p 8080:80 --name nginx nginx
curl localhost:8080
docker kill nginx && docker rm nginx
cat << EOF > index.html
hello world
EOF
docker run  -d -p 8080:80 -v ./index.html:/usr/share/nginx/html/index.html --name nginx nginx
curl localhost:8080
docker inspect nginx
docker inspect network bridge
docker run -d -p 8081:80 --name nginx2 nginx
docker inspect network bridge
docker kill nginx nginx2 && docker rm nginx nginx2

Kubernetes

Exercise 1:

kubeadm init --apiserver-advertise-address $(hostname -i) --pod-network-cidr 10.5.0.0/16
kubectl apply -f https://raw.githubusercontent.com/cloudnativelabs/kube-router/master/daemonset/kubeadm-kuberouter.yaml
kubeadm join 192.168.0.7:6443 --token gdq1k6.3zodxzisbii1kbsh \
        --discovery-token-ca-cert-hash sha256:39d0561a98d2c371c8ddda04d15a21cbbcff22a357e6356c9fd6fec1a49b194a

kubectl get -v 8 nodes

cat << EOF > nginx.yaml
apiVersion: v1
kind: Service
metadata:
  name: my-nginx-svc
  labels:
    app: nginx
spec:
  type: NodePort
  ports:
  - port: 80
  selector:
    app: nginx
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: my-nginx
  labels:
    app: nginx
spec:
  replicas: 3
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:1.14.2
        ports:
        - containerPort: 80
EOF

kubectl create -f nginx.yaml
kubectl get svc
curl localhost:<nodeport>
kubectl delete -f nginx.yaml

Exercise 2:

cat << EOF > nginx.yaml
apiVersion: v1
kind: Service
metadata:
  name: my-nginx-svc
  labels:
    app: nginx
spec:
  type: NodePort
  ports:
  - port: 80
  selector:
    app: nginx
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: my-nginx
  labels:
    app: nginx
spec:
  replicas: 3
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:1.14.2
        ports:
        - containerPort: 80
        volumeMounts:
          - name: config-volume
            mountPath: /usr/share/nginx/html/index.html
            subPath: index.html
      volumes:
        - name: config-volume
          configMap:
            # Provide the name of the ConfigMap containing the files you want
            # to add to the container
            name: nginx-config
---
apiVersion: v1
kind: ConfigMap
metadata:
  name: nginx-config
data:
  index.html: |
    hello world
EOF

kubectl create -f nginx.yaml
kubectl get svc
curl localhost:<nodeport>
kubectl delete -f nginx.yaml