CREATE A MULTI-CLOUD SETUP of K8S cluster!

Article for creating a multicloud k8s cluster

📌 CREATE A MULTI-CLOUD SETUP of K8S cluster :

🔅 Launch node in AWS
🔅 Launch node in Azure
🔅 Launch node in GCP
🔅 One node on cloud should be Master Node
🔅 Then setup multi node Kubernetes cluster.

So to do this task, I have created three nodes :

Master node on AWS, Slave nodes on AWS, Azure and GCP.

Let’s start :

Setting up Kubernetes master on AWS :

Step-1 : For installing kubelet, kubeadm, kubectl first, we need to set up a repo for this :

vim /etc/yum.repos.d/k8s.repo# content inside repo k8s.repo
[kubernetes]
name=Kubernetes
baseurl=https://packages.cloud.google.com/yum/repos/kubernetes-el7-\$basearch
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

Step-2 : Installing required softwares :

yum install docker kubelet kubeadm kubectl iproute-tc -y

Step-3 : Starting and enabling services :

systemctl enable --now docker
systemctl enable --now kubelet

Step-4 : We also need to pull docker images using kubeadm. It pulls images of the config files.

kubeadm config  images pull

Step-5 : Now, we need to change the docker cgroupdriver into systemd

vim /etc/docker/daemon.json

Step-6 : Since we have made changes in docker, we need to restart docker service :

systemctl restart docker

Step-7 : Setting up network bridge to 1 :

echo "1" > /proc/sys/net/bridge/bridge-nf-call-iptable

Step-8 : The important step is while initializing Master, while running preflight the main thing is we need to associate the token to the public IP of instance, so that any of the other nodes can easily connect, so for this use :

--control-plane-endpoint=<PUBLIC_IP>:6443kubeadm init --pod-network-cidr=10.244.0.0/16 --control-plane-endpoint=<public_ip>:6443 --ignore-preflight-errors=NumCPU          --ignore-preflight-errors=Mem

Step-9 : Now, make directory for kube config files and give permission to them :

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

Step-10 : Apply flannel :

kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

Step-11 : Final step : Generate token so that slave nodes could connect to master node :

kubeadm token create --print-join-command

Second : Setting up Kubernetes nodes on AWS, Azure, GCP :

(Follow same steps in all the three platforms)

♻ AWS

♻ Azure

♻ GCP

Step-1 : For installing kubelet, kubeadm, kubectl first, we need to set up a repo for this :

vim /etc/yum.repos.d/k8s.repo
# content inside repo k8s.repo
[kubernetes]
name=Kubernetes
baseurl=https://packages.cloud.google.com/yum/repos/kubernetes-el7-\$basearch
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

Step-2 : Installing required softwares :

yum install docker kubelet kubeadm kubectl iproute-tc -y

Step-3 : Starting and enabling services :

systemctl enable --now docker
systemctl enable --now kubelet

Step-4 : We also need to pull docker images using kubeadm. It pulls images of the config files :

kubeadm config  images pull

Step-5 : Now, we need to change the docker cgroupdriver into systemd :

vim /etc/docker/daemon.json
{  
"exec-opts": ["native.cgroupdriver=systemd"]
}

Step-6 : Since we have made changes in docker, we need to restart docker service :

systemctl restart docker

Step-7 : Setting up network bridge to 1 :

echo "1" > /proc/sys/net/bridge/bridge-nf-call-iptable

Step-8 : Copy paste the token generated in master node….

Finally, in master node :

kubectl get nodes

You will see the all the nodes are connected and are ready: