Install k8 with 2 nodes on centos7

Prerequisites:
– Disable swap
– Disable SElinux
– Disable Firewalld(optional if all k8 rule added)

Servers IP:
kmaster1 = 192.168.0.10
knode1 = 192.168.0.11
knode2 = 192.168.0.12

#Disable swap
swapoff -a

swapline=$(cat -n /etc/fstab | grep swap | awk '{print $1}')
if [ $(cat /etc/fstab | grep swap | awk '{print substr($0,0,1)}') != "#" ]
then
sed -i ""$swapline"s/.*/#&/" /etc/fstab
fi


#Disable SElinux
setenforce 0
sed -i  's/^SELINUX=enforcing$/SELINUX=permissive/' /etc/selinux/config

#Disable firewalld
systemctl stop firewalld
systemctl disable firewalld

#iptables conf
echo 'net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1' > /etc/sysctl.d/k8.conf

sysctl --system

Add Kubernetes Repository

echo '[kubernetes]
name=Kubernetes
baseurl=https://packages.cloud.google.com/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://packages.cloud.google.com/yum/doc/yum-key.gpg https://packages.cloud.google.com/yum/doc/rpm-package-key.gpg
' >  /etc/yum.repos.d/kubernetes.repo

On kmaster01

yum install -y kubelet kubeadm kubectl docker
systemctl enable kubelet
systemctl start kubelet
systemctl enable docker
systemctl start docker

hostnamectl set-hostname kmaster01

kubeadm init

At end of above command run below command and save the join command.

mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config

AND note the join command

Apply weave network:

kubectl apply -f "https://cloud.weave.works/k8s/net?k8s-version=$(kubectl version | base64 | tr -d '\n')"

On knode1:

yum install -y kubelet kubeadm kubectl docker
systemctl enable kubelet
systemctl start kubelet
systemctl enable docker
systemctl start docker

hostnamectl set-hostname knode1

#Join command
kubeadm join 192.168.0.10:6443 --token lfh49o.f9na1435g8vs1fmt \
     --discovery-token-ca-cert-hash sha256:0064f08a4c0ef36e454b683f61a68e0bf78d9cdb45f7905128c68b28fc2a5b3e

On knode2:

yum install -y kubelet kubeadm kubectl docker
systemctl enable kubelet
systemctl start kubelet
systemctl enable docker
systemctl start docker

hostnamectl set-hostname knode2

#Join command
kubeadm join 192.168.0.10:6443 --token lfh49o.f9na1435g8vs1fmt \
     --discovery-token-ca-cert-hash sha256:0064f08a4c0ef36e454b683f61a68e0bf78d9cdb45f7905128c68b28fc2a5b3e

nginx-app.yml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: my-nginx
spec:
  selector:
    matchLabels:
      run: my-nginx
  replicas: 2
  template:
    metadata:
      labels:
        run: my-nginx
    spec:
      containers:
      - name: my-nginx
        image: nginx
        ports:
        - containerPort: 80

nginx-svc.yml

apiVersion: v1
kind: Service
metadata:
  name: nginx-svc
  labels:
    run: nginx-svc
spec:
  type: NodePort
  ports:
  - port: 80
    protocol: TCP
  selector:
    run: my-nginx

kubectl apply -f ngix-app.yml
kubectl apply -f ngix-svc.yml