前言
本实验建立在Kubernetes单节点二进制部署基础之上。

实验环境

k8s集群master01:192.168.19.11  kube-apiserver kube-controller-manager kube-scheduler etcd
k8s集群master02:192.168.19.33 （为多节点准备）

k8s集群node01:192.168.19.44   kubelet kube-proxy docker flannel
k8s集群node02: 192.168.19.55

etcd集群节点1:192.168.19.11   etcd
etcd集群节点2:192.168.19.44
etcd集群节点3:192.168.19.55

负载均衡nginx+keepalive01 (master）:192.168.19.66
负载均衡nginx+keepalive02 (backup）:192.168.19.77

systemetl stop firewalld
systemctl disable firewalldsetenforce 0

一、部署master02 节点

修改主机名，关闭防火墙

# k8smaster02（192.168.19.33）
hostnamectl set-hostname k8smaster02
su
systemctl stop firewalld.service
systemctl disable firewalld.service
setenforce 0

# lb01（192.168.19.66）
hostnamectl set-hostname lb01
su
systemctl stop firewalld.service
systemctl disable firewalld.service
setenforce 0

# lb02（192.168.19.77）
hostnamectl set-hostname lb02
su
systemctl stop firewalld.service
systemctl disable firewalld.service
setenforce 0

在k8smaster01上操作

#从 k8smaster01 节点上拷贝证书文件、各master组件的配置文件和服务管理文件到 k8smaster02 节点
scp -r /opt/etcd/ root@192.168.19.33:/opt/
scp -r /opt/kubernetes/ root@192.168.19.33:/opt
scp /usr/lib/systemd/system/{kube-apiserver,kube-controller-manager,kube-scheduler}.service root@192.168.19.33:/usr/lib/systemd/system/

在k8smaster02上操作

#修改配置文件kube-apiserver中的IP
vim /opt/kubernetes/cfg/kube-apiserver
KUBE_APISERVER_OPTS="--logtostderr=true \
--v=4 \
--etcd-servers=https://192.168.19.11:2379,https://192.168.19.44:2379,https://192.168.19.55:2379 \
--bind-address=192.168.19.33 \				#修改
--secure-port=6443 \
--advertise-address=192.168.19.33 \			#修改
......

#在 master02 节点上启动各服务并设置开机自启
systemctl start kube-apiserver.service
systemctl enable kube-apiserver.service
systemctl start kube-controller-manager.service
systemctl enable kube-controller-manager.service
systemctl start kube-scheduler.service
systemctl enable kube-scheduler.service

#查看node节点状态
ln -s /opt/kubernetes/bin/* /usr/local/bin/
kubectl get nodes
kubectl get nodes -o wide			#-o=wide：输出额外信息；对于Pod，将输出Pod所在的Node名

#此时在master02节点查到的node节点状态仅是从etcd查询到的信息，而此时node节点实际上并未与master02节点建立通信连接，因此需要使用一个VIP把node节点与master节点都关联起来

二、部署负载均衡

配置load balancer集群双机热备负载均衡（nginx实现负载均衡，keepalived实现双机热备）

1.配置nginx的官方在线yum源，配置本地nginx的yum源

在lb01、lb02节点上操作

#配置nginx的官方在线yum源，配置本地nginx的yum源
cat > /etc/yum.repos.d/nginx.repo << 'EOF'
[nginx]
name=nginx repo
baseurl=http://nginx.org/packages/centos/7/$basearch/
gpgcheck=0
EOF

yum install -y nginx 

#修改nginx配置文件，配置四层反向代理负载均衡，指定k8s群集2台master的节点ip和6443端口
vim /etc/nginx/nginx.conf
events {
    worker_connections  1024;
}

#添加
stream {
    log_format  main  '$remote_addr $upstream_addr - [$time_local] $status $upstream_bytes_sent';
    
	access_log  /var/log/nginx/k8s-access.log  main;

    upstream k8s-apiserver {
        server 192.168.19.11:6443;
        server 192.168.19.33:6443;
    }
    server {
        listen 6443;
        proxy_pass k8s-apiserver;
    }
}

http {
......


#检查配置文件语法
nginx -t   

#启动nginx服务，查看已监听6443端口
systemctl start nginx
systemctl enable nginx
netstat -natp | grep nginx

2.部署keepalived服务

在lb01、lb02节点上操作

yum install keepalived -y

#修改keepalived配置文件
vim /etc/keepalived/keepalived.conf
! Configuration File for keepalived

global_defs {
   # 接收邮件地址
   notification_email {
     acassen@firewall.loc
     failover@firewall.loc
     sysadmin@firewall.loc
   }
   # 邮件发送地址
   notification_email_from Alexandre.Cassen@firewall.loc
   smtp_server 127.0.0.1
   smtp_connect_timeout 30
   router_id NGINX_MASTER	#lb01节点的为 NGINX_MASTER，lb02节点的为 NGINX_BACKUP
}

#添加一个周期性执行的脚本
vrrp_script check_nginx {
    script "/etc/nginx/check_nginx.sh"	#指定检查nginx存活的脚本路径
}

vrrp_instance VI_1 {
    state MASTER			#lb01节点的为 MASTER，lb02节点的为 BACKUP
    interface ens33			#指定网卡名称 ens33
    virtual_router_id 51	#指定vrid，两个节点要一致
    priority 100			#lb01节点的为 100，lb02节点的为 90
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.19.100/24	#指定 VIP
    }
    track_script {
        check_nginx			#指定vrrp_script配置的脚本
    }
}

#创建nginx状态检查脚本 
vim /etc/nginx/check_nginx.sh
#!/bin/bash
#egrep -cv "grep|$$" 用于过滤掉包含grep 或者 $$ 表示的当前Shell进程ID
count=$(ps -ef | grep nginx | egrep -cv "grep|$$")

if [ "$count" -eq 0 ];then
    systemctl stop keepalived
fi


chmod +x /etc/nginx/check_nginx.sh

#启动keepalived服务（一定要先启动了nginx服务，再启动keepalived服务）
systemctl start keepalived
systemctl enable keepalived
ip a				#查看VIP是否生成

3.修改k8snode节点上的bootstrap.kubeconfig,kubelet.kubeconfig配置文件为VIP

在node01和node02上操作

cd /opt/kubernetes/cfg/
ls
vim bootstrap.kubeconfig 
server: https://192.168.19.100:6443
                      
vim kubelet.kubeconfig
server: https://192.168.19.100:6443
                        
vim kube-proxy.kubeconfig
server: https://192.168.19.100:6443

#重启kubelet和kube-proxy服务
systemctl restart kubelet.service 
systemctl restart kube-proxy.service

4.在lb01上查看nginx的k8s日志

tail /var/log/nginx/k8s-access.log

三、测试

在 k8smaster01 节点上操作

#测试创建pod
kubectl run nginx --image=nginx

#查看Pod的状态信息
kubectl get pods
NAME                    READY   STATUS    RESTARTS   AGE
nginx-dbddb74b8-5n654   1/1     Running   0          41s

kubectl get pods -o wide
NAME                    READY   STATUS    RESTARTS   AGE   IP            NODE            NOMINATED NODE
nginx-dbddb74b8-5n654   1/1     Running   0          71s   172.17.52.3   192.168.19.44   <none>
#READY为1/1，表示这个Pod中有1个容器

#在对应网段的node节点上操作，可以直接使用浏览器或者curl命令访问
curl 172.17.52.3

#这时在master01节点上查看nginx日志，发现没有权限查看
kubectl logs nginx-dbddb74b8-5n654


#在master01节点上，将cluster-admin角色授予用户system:anonymous
kubectl create clusterrolebinding cluster-system-anonymous --clusterrole=cluster-admin --user=system:anonymous

#再次查看nginx日志
kubectl logs nginx-dbddb74b8-5n654