Centos8 使用kubeadm部署k8s集群

趁着春节体验了把Centos8，用着感觉和7没有太大变化，由于重新安装了Centos8，以前配置的k8s环境要重新配置了，在Centos8上配置docker和k8s遇到了不少坑，记录一下部署过程。

卸载podman，centos8默认安装了podman容器，它和docker有冲突需要卸载掉

yum delete podman

配置yum国内镜像

https://blog.youkuaiyun.com/wohendatou/article/details/102028632  参考

vim /etc/hostname  修改主机名k8sserver

关闭防火墙

systemctl disable firewalld

systemctl stop firewalld

关闭selinux

vim /etc/selinux/config 如下

# This file controls the state of SELinux on the system.
# SELINUX= can take one of these three values:
#     enforcing - SELinux security policy is enforced.
#     permissive - SELinux prints warnings instead of enforcing.
#     disabled - No SELinux policy is loaded.
SELINUX=disabled
# SELINUXTYPE= can take one of these three values:
#     targeted - Targeted processes are protected,
#     minimum - Modification of targeted policy. Only selected processes are protected. 
#     mls - Multi Level Security protection.
SELINUXTYPE=targeted

setenforce 0

 

关闭swap

swapoff -a

vim /etc/fstab 注释掉swap项

/dev/mapper/cl_zhangqiang-root /                       xfs     defaults        0 0
UUID=bbb5a6be-17cd-4c28-8772-7bf5416ab16f /boot                   ext4    defaults        1 2
/dev/mapper/cl_zhangqiang-home /home                   xfs     defaults        0 0
#/dev/mapper/cl_zhangqiang-swap swap                    swap    defaults        0 0

配置docker安装国内yum源

先安装yum-utils，centos8默认没有安装这个库，否则无法使用yum-config-manager命令。

yum install yum-utils

yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo

安装docker 

yum install docker-ce 安装最新版，也可以根据需要指定版本。

配置docker 国内yum源

vim /etc/yum.repos.d/kubernetes.repo

[kubernetes]
name=Kubernetes
baseurl=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/rpm-package-key.gpg

安装kubeadm、kubectl、kubelet

yum install -y kubelet kubeadm kubectl

启动kubelet服务

systemctl enable kubelet

systemctl start kubelet

初始化kubernetes集群

kubeadm init \
    --apiserver-advertise-address=当前机器的IP \
    --image-repository registry.aliyuncs.com/google_containers \
    --kubernetes-version v1.17.2 \
    --pod-network-cidr=10.244.0.0/16

配置集群配置文件

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

等待一段时间集群安装完成。

安装网络插件flannel(网络插件有很多)

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

查看集群状态

NAME         STATUS   ROLES    AGE   VERSION
zhangqiang   Ready    master   73m   v1.17.2

kube-system pod状态

NAME                                 READY   STATUS    RESTARTS   AGE   IP                NODE         NOMINATED NODE   READINESS GATES
coredns-9d85f5447-756wh              1/1     Running   1          74m   10.244.0.5        zhangqiang   <none>           <none>
coredns-9d85f5447-c4gsf              1/1     Running   1          74m   10.244.0.4        zhangqiang   <none>           <none>
etcd-zhangqiang                      1/1     Running   5          75m   192.168.124.134   zhangqiang   <none>           <none>
kube-apiserver-zhangqiang            1/1     Running   5          75m   192.168.124.134   zhangqiang   <none>           <none>
kube-controller-manager-zhangqiang   1/1     Running   5          75m   192.168.124.134   zhangqiang   <none>           <none>
kube-flannel-ds-amd64-h8g62          1/1     Running   1          63m   192.168.124.134   zhangqiang   <none>           <none>
kube-proxy-cjss4                     1/1     Running   5          74m   192.168.124.134   zhangqiang   <none>           <none>
kube-scheduler-zhangqiang            1/1     Running   5          75m   192.168.124.134   zhangqiang   <none>           <none>
kubernetes 单机集群部署完成........