[K8s][Commands]

k8s

use following commands to simulate kubernate clusters

0. configure static ip address

ip route | grep default

Open the Netplan configuration file:

sudo nano /etc/netplan/01-netcfg.yaml

Configure static IP: Add the following to the file:

network:
  version: 2
  ethernets:
    ens33: #Replace with your network card name
      addresses:
        - 192.168.1.10/24 # Set a fixed IP address
      routes:
        - to: default
          via: 192.168.1.1 #Set the gateway address
      nameservers:
        addresses:
          - 8.8.8.8
          - 8.8.4.4

sudo netplan apply

1. ssh

sudo apt update
sudo apt install openssh-server -y

sudo systemctl enable ssh
sudo systemctl start ssh

sudo systemctl status ssh

sudo vim /etc/fstab

#/swapfile none swap sw 0 0

sudo reboot
free -h

2. Master

• Disable Swap (if not disabled)

sudo swapoff -a
sudo sed -i '/swap/d' /etc/fstab

• Import the GPG public key of the Alibaba Cloud image

curl -fsSL https://mirrors.aliyun.com/kubernetes/apt/doc/apt-key.gpg | sudo gpg --dearmor -o /usr/share/keyrings/kubernetes-archive-keyring.gpg

sudo apt-get update

• Check /etc/apt/sources.list.d/kubernetes.list configuration

sudo rm -f /etc/apt/sources.list.d/kubernetes.list
echo "deb [signed-by=/usr/share/keyrings/kubernetes-archive-keyring.gpg] https://mirrors.aliyun.com/kubernetes/apt/ kubernetes-xenial main" | sudo tee /etc/apt/sources.list.d/kubernetes.list

• Update and install Kubernetes

sudo apt-get update
sudo apt-get install -y kubelet kubeadm kubectl

• Confirm whether the installation is successful

kubelet --version
kubeadm version
kubectl version --client

• Initialize the Kubernetes cluster. Run the following command to initialize the Kubernetes master node:

sudo kubeadm init --pod-network-cidr=192.186.0.0/16 --ignore-preflight-errors=Port-6443,Port-10259,Port-10257,Port-10250

• Set up kubectl to access the cluster

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

Test whether the connection is successful:

kubectl get nodes

bash
If the master node status is displayed as Ready, it means that the initialization is successful.

• Install network plugin (using Flannel)

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

• Add a working node

After the master node is initialized, copy the generated command to worker node by using the following command in the master node to join the worker node to the cluster:

sudo kubeadm token create --print-join-command

If need to deploy an application, can use kubectl apply or Helm deployment.

3. worker

sudo apt-get update && sudo apt-get install -y apt-transport-https ca-certificates curl software-properties-common


curl -fsSL https://mirrors.aliyun.com/kubernetes/apt/doc/apt-key.gpg | sudo gpg --dearmor -o /usr/share/keyrings/kubernetes-archive-keyring.gpg
echo "deb [signed-by=/usr/share/keyrings/kubernetes-archive-keyring.gpg] https://mirrors.aliyun.com/kubernetes/apt/ kubernetes-xenial main" | sudo tee /etc/apt/sources.list.d/kubernetes.list


sudo apt-get update
sudo apt-get install -y kubelet kubeadm kubectl


sudo apt-get install -y docker.io


sudo systemctl enable docker
sudo systemctl start docker
sudo systemctl enable kubelet

on worker:
mkdir -p $HOME/.kube


go to the master:
sudo scp /etc/kubernetes/admin.conf <worker-username>@<worker-node-ip-address>:/home/<worker-username>/.kube/config


back to the worker:
sudo chown $(id -u):$(id -g) $HOME/.kube/config

check the status:
kubectl get nodes