Deploy Simple App to Kubernetes Cluster using Jenkins

Eksekusi disemua node

Set name resolution

sudo vim /etc/hosts

10.0.1.97 an-master0
10.0.1.100 an-worker0
10.0.1.101 an-worker1

Update & Install package

apt update && apt upgrade -y
sudo apt install -y docker.io; sudo docker version
nano /etc/docker/daemon.json
...
{
   "insecure-registries" : ["10.0.1.97:5000"]
}
...
nano /lib/systemd/system/docker.service
#edit line like this :
...
ExecStart=/usr/bin/dockerd -H tcp://0.0.0.0:2375 -H fd:// --containerd=/run/containerd/containerd.sock
...
systemctl daemon-reload
sudo service docker restart

test Docker remote access

docker -H tcp://10.0.1.97:2375 version
docker -H tcp://10.0.1.101:2375 version
docker -H tcp://10.0.1.100:2375 version

Eksekusi di node an-master0

Create Private Docker registry

sudo docker run -d -p 5000:5000 --restart=always --name registry registry:2

Eksekusi disemua node

Install k8s

sudo apt install -y apt-transport-https; curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | sudo apt-key add -
sudo vi /etc/apt/sources.list.d/kubernetes.list
...
deb http://apt.kubernetes.io/ kubernetes-xenial main
...
sudo apt update; sudo apt install -y kubectl=1.15.4-00 kubelet=1.15.4-00 kubeadm=1.15.4-00

Eksekusi di node an-master0

sudo kubeadm init --pod-network-cidr=10.244.0.0/16
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config

Instal POD Network Flannel

wget https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
kubectl apply -f kube-flannel.yml
kubectl get pods --all-namespaces --watch

Tampilkan Token dan token-ca-cert-hash

sudo kubeadm token list
sudo openssl x509 -pubkey -in /etc/kubernetes/pki/ca.crt | openssl rsa -pubin -outform der 2>/dev/null | openssl dgst -sha256 -hex | sed 's/^.* //'

Eksekusi di node an-worker0 dan an-worker1

• Join Node Worker ke Master (pastikan swap tidak menyala)

swapon -s
sudo swapoff -a
sudo kubeadm join --token [TOKEN] [NODE-MASTER]:6443 --discovery-token-ca-cert-hash sha256:[TOKEN-CA-CERT-HASH]

Eksekusi di node an-master0

Clone repository

git clone https://github.com/misskecupbung/jenkins-k8s.git
cd jenkins-k8s/modified-images/

build images

docker build -t misskecupbung/jenkins-k8s:latest .
docker login
docker push misskecupbung/jenkins-k8s:latest

create deployment and service

kubectl apply -f jenkins-deployment.yaml 
kubectl apply -f jenkins-service.yaml 
kubectl get deployment,pod,service

Login ke Jenkins Dashboard

http://an-master0:30100

install plugin

Login -> Manage Jenkins -> Manage Plugins -> Available :

• Blue Ocean
• Kubernetes :: Pipeline :: DevOps Steps
• Kubernetes Cli Plugin
• Kubernetes Client API Plugin
• Kubernetes Continuous Deploy Plugin
• Kubernetes Credentials Plugin
• Kubernetes plugin

Manage Kubernetes

Login -> Manage Jenkins -> Configure System -> Add a new cloud > Kubernetes :

• Kubernetes URL : http://10.60.8.133:30100/
• Add Container Template :
  • Namespace : jenkins
  • Container name : jnlp
  • Docker images : joao29a/jnlp-slave-alpine-docker
• Apply/Save

Create credential

Login -> Credentials -> Jenkins -> Global credentials (unrestricted) -> Add Credential :

• kind: Kubernetes Configuration (kubeconfig)
• id: kubeconfig
• enter directy. (paste from /root/.kube/config in master node.)

Deploy App

Login -> Open Blue Ocean -> New Pipeline -> GitHub -> Select repository (Ex: jenkins-k8s) -> Create Pipeline

Test app

kubectl get deployment
kubectl get pods
kubectl get services
curl an-master0:32313

Set Time Trigger deploy

Login -> Jenkins-k8s -> Configure -> Scan repository triggers -> Periodically if not otherwise run -> Set interval: 1 minutes.