Demo Kubernetes on DC/OS

README.md

Setup

These instructions are for DC/OS 1.11.0 and Kubernetes package 1.0.0-1.9.3.

Service Accounts

Install the DC/OS Enterprise CLI, then create a keypair and a service account for Kubernetes. Securely store the private key in the DC/OS secrets store.

dcos package install dcos-enterprise-cli --yes
dcos security org service-accounts keypair private-key.pem public-key.pem
dcos security org service-accounts create -p public-key.pem -d 'kubernetes service account' kubernetes
dcos security secrets create-sa-secret private-key.pem kubernetes kubernetes/sa
dcos security org groups add_user superusers kubernetes

Cassandra

The app stores data in Cassandra. Install the package and create the schema.

dcos package install cassandra --yes
dcos node ssh --master-proxy --leader
docker run -it cassandra:3.0.13 cqlsh node-0-server.cassandra.autoip.dcos.thisdcos.directory

CREATE KEYSPACE browsers WITH REPLICATION = { 'class' : 'SimpleStrategy', 'replication_factor' : 1 };

CREATE TABLE browsers.browser_counts (
  counter counter,
  os varchar,
  PRIMARY KEY (os)
);

Demo

Public URL: http://k8s.dcos.io

Install Kubernetes

dcos package install --yes kubernetes --options=k8s-package-options.json

Show progress in the UI or CLI:

dcos kubernetes plan status deploy

Connect

dcos kubernetes kubeconfig
ssh -o "UserKnownHostsFile=/dev/null" -o "StrictHostKeyChecking=no" -N -L 9000:apiserver-insecure.kubernetes.l4lb.thisdcos.directory:9000 core@

Kubernetes dashboard

http://localhost:8001/api/v1/namespaces/kube-system/services/kubernetes-dashboard/proxy/

Using the CLI to manage Kubernetes

Use kubectl to deploy pods on Kubernetes.

kubectl create -f os-detector-white.yaml

kubectl get pods

kubectl describe pod NAME

kubectl set image deployment/osdetect osdetector=smugcloud/osdetector:purple

kubectl get pods

Scale up K8s cluster

Edit the number of nodes in the options file and run:

dcos kubernetes update --options=k8s-package-options.json

View progress in the UI or CLI:

dcos kubernetes plan status update

Kill and heal etcd

dcos task exec -it
pkill etcd
dcos task log

Version update

Can't do this with GA right now because there is only one GA version published.

dcos package install beta-kubernetes --package-version=0.6.0-1.9.1-beta --yes
dcos beta-kubernetes update --name=/kubernetes --package-version=0.6.1-1.9.3-beta --yes

Cleanup

dcos package uninstall kubernetes --yes
dcos security org service-accounts delete kubernetes
dcos security secrets delete kubernetes/sa

os-detector-purple.yaml

apiVersion: apps/v1beta1
kind: Deployment
metadata:
  name: osdetect
spec:
  replicas: 5
  template:
    metadata:
      name: osdetector
      labels:
        app: osdetector
    spec:
      containers:
      - name: osdetector
        image: smugcloud/osdetector:purple
        imagePullPolicy: Always
        args: ["--cassandra-host", "node-0-server.cassandra.autoip.dcos.thisdcos.directory"]
        ports:
        - containerPort: 8080
---

kind: Service
apiVersion: v1
metadata:
  name: osdetect
spec:
  selector:
    app: osdetector
  ports:
    - protocol: TCP
      port: 80
      targetPort: 8080
      nodePort: 31000
  type: NodePort

os-detector-white.yaml

apiVersion: apps/v1beta1
kind: Deployment
metadata:
  name: osdetect
spec:
  replicas: 5
  template:
    metadata:
      name: osdetector
      labels:
        app: osdetector
    spec:
      containers:
      - name: osdetector
        image: smugcloud/osdetector:white
        imagePullPolicy: Always
        args: ["--cassandra-host", "node-0-server.cassandra.autoip.dcos.thisdcos.directory:9042"]
        ports:
        - containerPort: 8080
---

kind: Service
apiVersion: v1
metadata:
  name: osdetect
spec:
  selector:
    app: osdetector
  ports:
    - protocol: TCP
      port: 80
      targetPort: 8080
      nodePort: 31000
  type: NodePort