第一步，购买三台云主机
系统 ubuntu 20.04 64位
配置 2 vCPU 4 GiB
机器名称 master-k8s, node1-k8s, node2-k8s
第二步，登录机器，关闭swap
以下命令没有特殊说明的，三台机器都要执行
# 临时关闭
root@master-k8s:~# swapoff -a
# 永久关闭
root@master-k8s:~# sed -ri 's/.*swap.*/#&/' /etc/fstab
第三步，将网桥的ip4流量转接到iptables
cat > /etc/sysctl.d/k8s.conf << EOF
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF
-- 效果 --
root@master-k8s:~# cat /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
使流量转接生效
sysctl --system
第四步，安装docker
docker是目前最流行的容器运行时
apt-get remove docker docker-engine docker.io containerd runc # 卸载原有docker, 新机器不用执行
apt-get update
apt-get install ca-certificates curl gnupg lsb-release
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo gpg --dearmor -o /usr/share/keyrings/docker-archive-keyring.gpg
echo \
"deb [arch=$(dpkg --print-architecture) signed-by=/usr/share/keyrings/docker-archive-keyring.gpg] https://download.docker.com/linux/ubuntu \
$(lsb_release -cs) stable" | sudo tee /etc/apt/sources.list.d/docker.list > /dev/null
apt-get update
apt-get install -y docker-ce docker-ce-cli containerd.io # 安装docker全家桶
docker run hello-world # 验证docker是否安装成功
输出如下表示安装成功
...
Hello from Docker!
...
第五步，配置docker镜像加速
cat > /etc/docker/daemon.json << EOF
{
"registry-mirrors": ["https://b9pmyelo.mirror.aliyuncs.com"],
"exec-opts": ["native.cgroupdriver=systemd"]
}
EOF
systemctl restart docker
第六步，配置Kubernetes镜像源
apt-get update && apt-get install -y apt-transport-https
curl -fsSL https://mirrors.aliyun.com/kubernetes/apt/doc/apt-key.gpg | apt-key add -
cat <<EOF >/etc/apt/sources.list.d/kubernetes.list
deb https://mirrors.aliyun.com/kubernetes/apt/ kubernetes-xenial main
EOF
sudo apt-get update
第七步，安装Kubernetes
apt-get install -y kubelet=1.23.0-00 kubeadm=1.23.0-00 kubectl=1.23.0-00
第八步，启动部署Kubernetes master
初始化kubeadm（仅在master上进行）
kubeadm init \
--image-repository registry.aliyuncs.com/google_containers \
--kubernetes-version v1.23.0 \
--service-cidr=10.96.0.0/12 \
--pod-network-cidr=10.244.0.0/16 \
--ignore-preflight-errors=all
输出效果部分如下
...
Your Kubernetes control-plane has initialized successfully!
To start using your cluster, you need to run the following as a regular user:
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config
Alternatively, if you are the root user, you can run:
export KUBECONFIG=/etc/kubernetes/admin.conf
You should now deploy a pod network to the cluster.
Run "kubectl apply -f [podnetwork].yaml" with one of the options listed at:
https://kubernetes.io/docs/concepts/cluster-administration/addons/
Then you can join any number of worker nodes by running the following on each as root:
kubeadm join 172.30.70.63:6443 --token lddban.k77fwxj5fmyt3wqj \
--discovery-token-ca-cert-hash sha256:71a7c5198a7ddfa441da244d16efe5508d640a9cbea0fbeab1bc1fca7cd153b2
配置文件处理（仅在master上进行）
mkdir -p $HOME/.kube
cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
chown $(id -u):$(id -g) $HOME/.kube/config
echo 'export KUBECONFIG=$HOME/.kube/config' >> $HOME/.bashrc
source ~/.bashrc
第九步，将node加入集群
仅在node1-k8s和node2-k8s上执行
kubeadm join 172.30.70.63:6443 --token lddban.k77fwxj5fmyt3wqj \
--discovery-token-ca-cert-hash sha256:71a7c5198a7ddfa441da244d16efe5508d640a9cbea0fbeab1bc1fca7cd153b2
注意删除空格
echo 'export KUBECONFIG=/etc/kubernetes/kubelet.conf' >> $HOME/.bashrc
chown $(id -u):$(id -g) /etc/kubernetes/kubelet.conf
source ~/.bashrc
此时回到，master-k8s，执行如下检查
root@master-k8s:~# kubectl get nodes
NAME STATUS ROLES AGE VERSION
master-k8s NotReady control-plane,master 8m51s v1.23.0
node1-k8s NotReady <none> 87s v1.23.0
node2-k8s NotReady <none> 82s v1.23.0
第十步，配置网络，检查节点状态
以上，会发现节点已经挂接到集群，但是当前都是notready状态，这是因为集群网络还没有配置，当前k8s主流网络配置方案是calico，配置方式如下：
# 在主节点执行
wget https://docs.projectcalico.org/manifests/calico.yaml
kubectl apply -f calico.yaml
马上执行kubectl get pods -n kube-system
root@master-k8s:~# kubectl get pods -n kube-system
NAME READY STATUS RESTARTS AGE
calico-kube-controllers-6b77fff45-fp2cj 0/1 Pending 0 8s
calico-node-9tf5w 0/1 Init:0/2 0 8s
calico-node-dx5bq 0/1 Init:0/2 0 8s
calico-node-x78f8 0/1 Init:0/2 0 8s
coredns-6d8c4cb4d-6wpt2 0/1 Pending 0 11m
coredns-6d8c4cb4d-dvqvj 0/1 Pending 0 11m
etcd-master-k8s 1/1 Running 0 11m
kube-apiserver-master-k8s 1/1 Running 0 11m
kube-controller-manager-master-k8s 1/1 Running 0 11m
kube-proxy-87tbj 1/1 Running 0 4m17s
kube-proxy-9w9lv 1/1 Running 0 4m22s
kube-proxy-s2j4f 1/1 Running 0 11m
kube-scheduler-master-k8s 1/1 Running 0 11m
可以发现calico-node-*还是Init:0/2状态，等一段时间，比如20秒，再次执行以上命令
root@master-k8s:~# kubectl get pods -n kube-system
NAME READY STATUS RESTARTS AGE
calico-kube-controllers-6b77fff45-fp2cj 1/1 Running 0 2m59s
calico-node-9tf5w 1/1 Running 0 2m59s
calico-node-dx5bq 1/1 Running 0 2m59s
calico-node-x78f8 1/1 Running 0 2m59s
coredns-6d8c4cb4d-6wpt2 1/1 Running 0 14m
coredns-6d8c4cb4d-dvqvj 1/1 Running 0 14m
etcd-master-k8s 1/1 Running 0 14m
kube-apiserver-master-k8s 1/1 Running 0 14m
kube-controller-manager-master-k8s 1/1 Running 0 14m
kube-proxy-87tbj 1/1 Running 0 7m8s
kube-proxy-9w9lv 1/1 Running 0 7m13s
kube-proxy-s2j4f 1/1 Running 0 14m
kube-scheduler-master-k8s 1/1 Running 0 14m
现在已经是Running状态了，使用kubectl get nodes查看节点状态，现在已经都是Ready状态了
root@master-k8s:~# kubectl get nodes
NAME STATUS ROLES AGE VERSION
master-k8s Ready control-plane,master 15m v1.23.0
node1-k8s Ready <none> 7m44s v1.23.0
node2-k8s Ready <none> 7m39s v1.23.0
root@master-k8s:~# kubectl cluster-info
Kubernetes control plane is running at https://172.30.70.63:6443
CoreDNS is running at https://172.30.70.63:6443/api/v1/namespaces/kube-system/services/kube-dns:dns/proxy
To further debug and diagnose cluster problems, use 'kubectl cluster-info dump'.
