Self Hosted Kubernetes Cluster using kubeadm

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Check connectivity between master and slave

ping IP

Disable swap

sudo swapoff -a  
cat /proc/meminfo | grep 'SwapTotal'
free -h

prepare

sudo apt get update
sudo apt install -y net-tools vim git curl wget netcat

sudo which nft >/dev/null && echo nftables is enabled in this system || echo ufw is enabled in this system

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On Control Panel aka master node allow relavent ports

sudo which nft >/dev/null && echo nftables is enabled in this system || echo ufw is enabled in this system

nc 127.0.0.1 6443
sudo netstat -tulpn | grep LISTEN
nc -zv  127.0.0.1 22
nc -zv  127.0.0.1 6443
netstat -lntu
ss -lntu

sudo apt install ufw
sudo ufw default allow outgoing
sudo ufw allow ssh
sudo ufw allow 6443
sudo ufw allow 2379:2380/tcp
sudo ufw allow 30000:32768/tcp
sudo ufw allow 10250
sudo ufw allow 10259
sudo ufw allow 10257
sudo ufw enable
sudo ufw status

On Worker node(s) relavent ports

netstat -lntu
ss -lntu

sudo apt install ufw
sudo ufw default allow outgoing
sudo ufw allow ssh
sudo ufw allow 10250
sudo ufw allow 30000:32767/tcp
sudo ufw enable
sudo ufw status

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Install docker from the given link Install Docker

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For Docker you need to install cri-dockerd

git clone https://github.com/Mirantis/cri-dockerd.git

To install cri-dockerd you need to install Go programming Language Download and install Go specific to your CPU architecture After installing go

echo "export PATH=$PATH:/usr/local/go/bin" >> ~/.profile 
source ~/.profile 
go version

Compile and install cri-dockerd

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Forwarding IPv4 and letting iptables see bridged traffic

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Installing kubeadm, kubelet and kubectl

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After installation kubeadm init

sudo kubeadm init --pod-network-cidr=192.168.0.0/16 --control-plane-endpoint=172.31.0.47 --cri-socket=unix:///var/run/cri-dockerd.sock

• --pod-network-cidr=192.168.0.0/16 because Calico supports 192.168.0.0/16 and I can use Acalico

Install Calico to provide both networking and network policy for self-managed on-premises deployments.

• --cri-socket=unix:///var/run/cri-dockerd.sock pass cri socket for cri-dockerd
• Install docker and docker-cri

Install kubeadm, kubelet and kubectl

sudo kubeadm join IP:6443 --token TOKEN --discovery-token-ca-cert-hash CERT --cri-socket=unix:///var/run/cri-dockerd.sock

Dont forget to pass --cri-socket=unix:///var/run/cri-dockerd.sock

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--control-plane-endpoint=172.31.0.47 private Ip here

kubectl get pods -A

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After kubeadm init follow the output given by the command

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Setup Calico
Install Calico networking and network policy for on-premises deployments directly jump to Install Calico Manifest Tab and follow "Install Calico with Kubernetes API datastore, 50 nodes or less"

kubectl get pods -A

kubectl get pods -A --watch
kubectl get namespaces
kubectl get all -n kube-system

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On the Worker Node

kubeadm join after link is expired