use kubeadmin install k8s in ubuntu

准备环境

• 至少2台机器或虚拟机（一个master，多个worker）
• 每台机器 2 GB 内存或更多
• 每台机器 2 CPU 核心或更多
• 集群中的所有机器的网络彼此均能相互连接(公网和内网都可以)
• 禁用 Swap 交换分区。

安装软件

# 每台机器都需要安装
apt-get update && apt-get install -y apt-transport-https curl
curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | apt-key add -
cat <<EOF >/etc/apt/sources.list.d/kubernetes.list
deb https://apt.kubernetes.io/ kubernetes-xenial main
EOF
apt-get update
apt-get install -y kubelet kubeadm kubectl
apt-mark hold kubelet kubeadm kubectl

master node 初始化

# 选择一台作为 master
# 在 master 上执行
kubeadm init

执行成功后，会输出 token 。
其他worker 使用此 token 加入到 kubernetes 集群。

Then you can join any number of worker nodes by running the following on each as root:
kubeadm join 10.176.7.9:6443 --token hh6cfg.ijmppt2fpry2dqr9
--discovery-token-ca-cert-hash sha256:c862aa8398c66300678371f1276cf6ffe02d589a17dc722c4eedb9ccd1db0282

worker node 加入 kubernetes 集群

# 在worker 上执行
kubeadm join 10.176.7.9:6443 --token hh6cfg.ijmppt2fpry2dqr9 \
    --discovery-token-ca-cert-hash sha256:c862aa8398c66300678371f1276cf6ffe02d589a17dc722c4eedb9ccd1db0282

token 24小时后会过期，可重新获取token

# 重新生成token
kubeadm token create
# 获取ca证书sha256编码hash值
openssl x509 -pubkey -in /etc/kubernetes/pki/ca.crt | openssl rsa -pubin -outform der 2>/dev/null | openssl dgst -sha256 -hex | sed 's/^.* //'
# join到集群
kubeadm join 10.176.7.9:6443 --token {token} --discovery-token-ca-cert-hash sha256:{hash}

安装Pod网络插件 - weave

# 在 master 上执行
export kubever=$(kubectl version | base64 | tr -d '\n') 
wget https://cloud.weave.works/k8s/net?k8s-version=$kubever -O weave.yaml 
kubectl apply -f weave.yaml

验证是否安装成功

kubernetes@km:~$ kubectl get nodes
NAME   STATUS   ROLES    AGE   VERSION
km     Ready    master   58m   v1.16.2
kw1    Ready    <none>   41m   v1.16.2
kw2    Ready    <none>   39m   v1.16.2

kubernetes@km:~$ kubectl get pods --all-namespaces -o wide
NAMESPACE     NAME                         READY   STATUS    RESTARTS   AGE   IP              NODE   NOMINATED NODE   READINESS GATES
kube-system   coredns-5644d7b6d9-pfp4r     1/1     Running   0          58m   10.32.0.2       km     <none>           <none>
kube-system   coredns-5644d7b6d9-w98kd     1/1     Running   0          58m   10.32.0.3       km     <none>           <none>
kube-system   etcd-km                      1/1     Running   0          57m   10.176.7.9      km     <none>           <none>
kube-system   kube-apiserver-km            1/1     Running   0          57m   10.176.7.9      km     <none>           <none>
kube-system   kube-controller-manager-km   1/1     Running   0          57m   10.176.7.9      km     <none>           <none>
kube-system   kube-proxy-2nnzx             1/1     Running   0          42m   10.176.9.51     kw1    <none>           <none>
kube-system   kube-proxy-bxhf2             1/1     Running   0          58m   10.176.7.9      km     <none>           <none>
kube-system   kube-proxy-mzqx6             1/1     Running   0          39m   10.176.12.157   kw2    <none>           <none>
kube-system   kube-scheduler-km            1/1     Running   0          57m   10.176.7.9      km     <none>           <none>
kube-system   weave-net-fjzkw              2/2     Running   0          39m   10.176.12.157   kw2    <none>           <none>
kube-system   weave-net-gjpnn              2/2     Running   0          42m   10.176.9.51     kw1    <none>           <none>
kube-system   weave-net-pk682              2/2     Running   0          53m   10.176.7.9      km     <none>           <none>

使用普通用户访问kubernetes

# 在master节点执行
# 切换到个人用户
mkdir $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config

然后将config文件内容拷贝至其他worker节点，或者个人PC里（$HOME/.kube/config），即可在worker以及个人PC上执行kubectl命令

link

https://kubernetes.io/zh/docs/setup/independent/install-kubeadm/
https://kubernetes.io/zh/docs/setup/independent/create-cluster-kubeadm/
https://blog.csdn.net/mailjoin/article/details/79686934