如何在CentOS7上安装kubernetes
1、修改主机和host解析，关闭selinux
192.168.20.11 k8s-master
192.168.20.12 k8s-node-1
192.168.20.13 k8s-node-2
2、所有节点安装docker-1.12.6-68
上传安装包。
yum localinstall docker-common-1.12.6-68.gitec8512b.el7.centos.x86_64.rpm -y
yum localinstall docker-client-1.12.6-68.gitec8512b.el7.centos.x86_64.rpm -y
yum localinstall docker-1.12.6-68.gitec8512b.el7.centos.x86_64.rpm -y
链接：https://pan.baidu.com/s/1nUCPUc4yOzumJeTtriIdkQ
提取码：o05o
3、master节点安装etcd
yum install etcd -y
修改配置文件
vim /etc/etcd/etcd.conf
ETCD_LISTEN_CLIENT_URLS="http://0.0.0.0:2379"
ETCD_ADVERTISE_CLIENT_URLS="http://192.168.20.11:2379"
加入开机自启动
systemctl start etcd.service
systemctl enable etcd.service
4、测试：
etcdctl set test/test-key 0
etcdctl get test/test-key
检查集群状态
etcdctl -C http://192.168.20.11:2379 cluster-health
5、master节点安装kubernetes
yum install kubernetes-master.x86_64 -y
修改apiserver配置文件
vim /etc/kubernetes/apiserver
KUBE_API_ADDRESS="--insecure-bind-address=0.0.0.0"
KUBE_API_PORT="--port=8080"
KUBE_ETCD_SERVERS="--etcd-servers=http://192.168.20.11:2379"
# node节点监听的端口
KUBELET_PORT="--kubelet-port=10250"
KUBE_ADMISSION_CONTROL="--admission-control=NamespaceLifecycle,NamespaceExists,LimitRanger,SecurityContextDeny ,Resour
ceQuota"
修改配置文件
vim /etc/kubernetes/config
#apiserver运行在哪，谁就是KUBE_MASTER
KUBE_MASTER="--master=http://192.168.20.11:8080"
systemctl enable kube-apiserver.service
systemctl start kube-apiserver.service
systemctl enable kube-controller-manager.service
systemctl start kube-controller-manager.service
systemctl enable kube-scheduler.service
其中个组建的功能：
api-server：接收并相应用户的请求
controller：控制器的概念，保证docker容器存活
schedule：调度器，选择启动容器的node节点
6、两台node节点安装kubernetes
yum install kubernetes-node.x86_64 -y
修改配置文件
vim /etc/kubernetes/config
KUBE_MASTER="--master=http://192.168.20.11:8080"
vim /etc/kubernetes/kubelet
KUBELET_ADDRESS="--address=0.0.0.0"
KUBELET_PORT="--port=10250"
# node节点主机名或IP地址
KUBELET_HOSTNAME="--hostname-override=192.168.20.12"
KUBELET_API_SERVER="--api-servers=http://192.168.20.11:8080"
systemctl enable kubelet.service
systemctl restart kubelet.service
systemctl enable kube-proxy.service
systemctl restart kube-proxy.service
其中个组建的功能：
kubelet：调用docker管理容器的生命周期
kube-proxy：提供容器的网络
7、检查能否出结果：
[root@k8s-master tools]# kubectl get nodes
8、所有节点配置flannel网络
yum install flannel -y
vim /etc/sysconfig/flanneld
也可以使用命令替换：
sed -i 's#http://127.0.0.1:2379#http://192.168.20.11:2379#g' /etc/sysconfig/flanneld
master上操作，创建网络和子网，以及类型
etcdctl mk /atomic.io/network/config '{
"Network": "10.2.0.0/16",
"SubnetLen": 24,
"Backend": {
"Type": "vxlan"
}
}
'
其中/atomic.io/network为
指定 etcd 存放 flannel 网络配置信息的 key
9、配置开机启动和重启k8s
master节点：
systemctl enable flanneld.service
systemctl start flanneld.service
service docker restart
systemctl restart kube-apiserver.service
systemctl restart kube-controller-manager.service
systemctl restart kube-scheduler.service
node节点：
systemctl enable flanneld.service
systemctl start flanneld.service
service docker restart
systemctl restart kubelet.service
systemctl restart kube-proxy.service
10、flanneld 启动后，宿主机网络会发生一些变化
使用ip add命令查看宿主机网络
11、每个节点启动busybox测试连通性（注意在docker 上配置加速）
[root@k8s-master tools]# docker run -it busybox /bin/bash
[root@k8s-node-1 ~]# docker run -it busybox /bin/bash
[root@k8s-node-2 ~]# docker run -it busybox /bin/sh
在master上ping其他的节点
12、配置master为镜像仓库
docker run -d -p 5000:5000 --restart=always --name registry -v /opt/myregistry:/var/lib/registry registry
修改连接访问仓库不使用HTTPS
master:
vim /etc/sysconfig/docker
OPTIONS='--selinux-enabled --log-driver=journald --signature-verification=false --insecure-registry=192.168.20.11:5000'
systemctl restart docker
node节点
vim /etc/sysconfig/docker
OPTIONS='--selinux-enabled --log-driver=journald --signature-verification=false --insecure-registry=192.168.20.11:5000'
systemctl restart docker
13、安装k8s完毕