概览

使用kubeadm部署高可用的k8s集群

环境&版本

centos 7.4+
kubernetes 1.14
3台机器，ip为ip1,ip2,ip3，机器配置4核8G

准备工作

所有集群机器都需要执行如下操作

配置yum源

使用阿里源

cat <<EOF > /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=[https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64](https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64)
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=[https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg](https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg)[https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg](https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg)
EOF

系统配置

关闭selinux

# 临时关闭
setenforce 0
# 永久关闭修改/etc/selinux/config
SELINUX=disabled

关闭防火墙

systemctl stop firewalld
systemctl disable firewalld

关闭swap

swapoff -a #临时关闭，重启后恢复
sed -i 's/.*swap.*/#&/' /etc/fstab #从开机启动中去掉

安装依赖

yum install -y kubelet kubeadm kubectl
systemctl enable kubelet.service
systemctl enable docker

部署架构

vip：虚拟ip，apiserver的外部访问ip，需要和所有node ip在同一网段
etcd：ip1，ip2，ip3
keepalived：ip1，ip2
master：ip1，ip2，ip3

部署keepalived

部署机器ip1，ip2
部署方法
https://qizhanming.com/blog/2018/05/17/how-to-config-keepalived-on-centos-7

准备kubeadm.yaml

apiVersion: kubeadm.k8s.io/v1beta1
kind: ClusterConfiguration
kubernetesVersion: stable
apiServer:
  certSANs:
  - "vip" # apiserver对外地址
  - "ip1"
  - "ip2"
  - "ip3"
controlPlaneEndpoint: "vip:6443" # apiserver对外地址
networking:
  dnsDomain: cluster.local
  podSubnet: 10.244.0.0/16

初始化第一个master

kubeadm init --config kubeadm.yaml

执行成功会显示token，用于其他节点加入，记录下来
部署网络插件，使用flannel

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

拷贝证书到其他master

# 打包证书
$ sudo tar zcvf certs.tar.gz /etc/kubernetes/admin.conf /etc/kubernetes/pki/ca.crt /etc/kubernetes/pki/ca.key /etc/kubernetes/pki/sa.key /etc/kubernetes/pki/sa.pub /etc/kubernetes/pki/front-proxy-ca.crt /etc/kubernetes/pki/front-proxy-ca.key /etc/kubernetes/pki/etcd/ca.crt /etc/kubernetes/pki/etcd/ca.key
# 将证书拷贝到其他master对应的位置，解压

初始化其他master

kubeadm join vip:6443 --token <token> --discovery-token-ca-cert-hash sha256:<hash> --experimental-control-plane

设置master参与调度

可选

kubectl taint nodes --all node-role.kubernetes.io/master-

完成安装