# 透過 kubeadm 安裝 k8s
###### tags: `install`
在 oci 上建立三個 instance 組成一個 k8s cluster
k8s version: 1.26

master node * 1
- Canonical-Ubuntu-20.04-2023.02.15-0
- 1 core
- 16 G

worker node * 2
- Canonical-Ubuntu-20.04-2023.02.15-0
- 1 core
- 16 G

subnet 中要注意
1. 22 port
2. 6443 port

## 關閉萬惡根源

sudo iptables -F

## 關閉 swap

swapoff -a

## 將其他 node 加進 /etc/hosts

sudo vim /etc/hosts

## 安裝 docker
當然也可以安裝其他 CRI 拉，但我懶

sudo apt-get update

sudo apt-get install -y docker.io

## 建立 k8s 環境

sudo apt-get update && sudo apt-get install -y apt-transport-https curl

curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | sudo apt-key add -

sudo touch /etc/apt/sources.list.d/kubernetes.list

vim /etc/apt/sources.list.d/kubernetes.list
# 加入
deb http://apt.kubernetes.io/ kubernetes-xenial main

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

## 修改 config 設定(optional)

sudo vim /etc/systemd/system/kubelet.service.d/10-kubeadm.conf
# 加入
Environment="cgroup-driver=systemd/cgroup-driver=cgroupfs"

[官網文件](https://kubernetes.io/zh-cn/docs/tasks/administer-cluster/kubeadm/configure-cgroup-driver/)

## 建立 master node
使用 calico 配置

sudo kubeadm init --pod-network-cidr=192.168.0.0/16 --apiserver-advertise-address=<master-node-ip>

## 建立 worker node

sudo kubeadm join <app-server> --token <token> --discovery-token-ca-cert-hash <hash> 

## 建立 kubeconfig

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

## 設定 CNI
calico

curl https://docs.projectcalico.org/v3.19/manifests/calico.yaml -O

# optional
sed -i -e "s?192.168.0.0/16?$POD_CIDR?g" calico.yaml

kubectl apply -f calico.yaml

結果

ubuntu@instance-20230321-danny-master:~$ kubectl get nodes
NAME                               STATUS   ROLES           AGE    VERSION
instance-20230321-danny-master     Ready    control-plane   162m   v1.26.3
instance-20230321-danny-worker01   Ready    <none>          157m   v1.26.3
instance-20230321-danny-worker02   Ready    <none>          47m    v1.26.3
# 設定 node label
kubectl label node instance-20230321-danny-worker02 node-role.kubernetes.io/worker=worker

ubuntu@instance-20230321-danny-master:~$ kubectl get po -A
NAMESPACE     NAME                                                     READY   STATUS    RESTARTS   AGE
kube-system   calico-kube-controllers-8674f7b57b-xgzbk                 1/1     Running   0          135m
kube-system   calico-node-25rrf                                        0/1     Running   0          136m
kube-system   calico-node-lx5d4                                        0/1     Running   0          47m
kube-system   calico-node-rw845                                        0/1     Running   0          136m
kube-system   coredns-787d4945fb-jcblz                                 1/1     Running   0          161m
kube-system   coredns-787d4945fb-w9swq                                 1/1     Running   0          161m
kube-system   etcd-instance-20230321-danny-master                      1/1     Running   2          161m
kube-system   kube-apiserver-instance-20230321-danny-master            1/1     Running   2          161m
kube-system   kube-controller-manager-instance-20230321-danny-master   1/1     Running   0          161m
kube-system   kube-proxy-4pwh2                                         1/1     Running   0          161m
kube-system   kube-proxy-q8dsf                                         1/1     Running   0          156m
kube-system   kube-proxy-vjkc8                                         1/1     Running   0          47m
kube-system   kube-scheduler-instance-20230321-danny-master            1/1     Running   2          161m