evalle/kubernetes-demo

OpenStack Magnum and Kubernetes demo

OpenStack Magnum & Kubernetes demo

This repo contains Kubernetes demo with modified guestbook example for Kubernetes cluster setup without skyDNS addon installed. It relays on environment variables, that's way it is important to deploy all components in proper order according to this documentation.

Installatation

Deploy OpenStack with Magnum

This demo requires full OpenStack installation with Magnum component, it can be done for example with SUSE OpenStack Cloud 7. For proper demo it is required to prepare at least 3 Nova Computes with kvm as hypervisor.

Prepare OpenStack environment

Download and upload Magnum SLES based image.

Link to the image http://download.suse.de/ibs/Devel:/Docker:/Images:/SLE12SP2-JeOS-k8s-magnum/images/sles-openstack-magnum-kubernetes.x86_64.qcow2

Source credentials

source .openrc

Upload image to Glance service

glance image-create --name sles-openstack-magnum-kubernetes \
                    --visibility public \
                    --disk-format qcow2 \
                    --os-distro opensuse \
                    --container-format bare \
                    --file ./sles-openstack-magnum-kubernetes.x86_64.qcow2

Import SSH key from controller node to use with the cluster template

nova keypair-add --pub-key ~/.ssh/id_rsa.pub default

Create Magnum flavor

nova flavor-create --is-public true m1.magnum 9 1024 10 1

Prepare OpenStack Magnum and deploy Kubernetes cluster

Create cluster template

magnum cluster-template-create --name k8s_template \
                       --image-id sles-openstack-magnum-kubernetes \
                       --keypair-id default \
                       --external-network-id floating \
                       --dns-nameserver 8.8.8.8 \
                       --flavor-id m1.magnum \
                       --master-flavor-id m1.magnum \
                       --docker-volume-size 5 \
                       --network-driver flannel \
                       --coe kubernetes \
                       --floating-ip-enabled \
                       --tls-disabled

Create a cluster with one kube-master node and one kube-minion node

magnum cluster-create --name k8s_cluster --cluster-template k8s_template --master-count 1 --node-count 2

Deploy guestbook application on Kubernetes cluster

Clone guestbook example from this repository on node with docker installed and credentials for Kubernetes cluster deplyed by Magnum

git clone https://github.com/mjura/kubernetes-demo

And go to the example

cd ~/kubernetes-demo/examples/guestbook

Check if Kubernetes cluster is healthy and you have right endpoints crendtials

kubectl cluster-info

Deploy redis-master replication controller and service

kubectl create -f redis-master-controller.yaml
kubectl create -f redis-master-service.yaml

Check status for replication controllers, pods and service

kubectl get rc,pods,service

Deploy redis-slave replication controller and service

kubectl create -f redis-slave-controller.yaml
kubectl create -f redis-slave-service.yaml

Check status for replication controllers, pods and service

kubectl get rc,pods,service

When redis-slave pods will be ready, auto-scale it and add one more replica

kubectl scale --replicas=2 rc/redis-slave

Check logs from redis-slave to be sure that they are replicating database from redis-master

kubectl logs <redis-slave-PODID>

Deploy frontend web application

kubectl create -f frontend-controller.yaml
kubectl create -f frontend-service.yaml

You should get service port (tcp:3XXXX) as output to configure Neutron LoadBalancer. Create Neutron LoadBalancer new pool named guestbook, add VIP and Floating IP, as members of this pool pick up kube-mionions

Access application using Floating IP

Modify guestbook application and demonstrate rolling-updates

Go to container application template

cd ~/kubernetes/examples/guestbook/php-redis/

Edit index.html file and uncomment line with image src

<!-- <img src="suse-logo.png" alt="SUSE Logo"> -->

to

<img src="suse-logo.png" alt="SUSE Logo">

Build new docker image and push it to docker-registry service

docker build -t docker.io/mjura/guestbook:v2 .
docker push docker.io/mjura/guestbook:v2

Deploy new version of application using rolling update feature from Kubernetes

kubectl rolling-update frontend --image=docker.io/mjura/guestbook:v2

After this will be done refresh webrowser with link to application